Here's what our customers have to say about us......
I'll be selecting a few of the hundreds of Thank You messages we receive.

We've been so busy I haven't had time to update this page lately, so here's a few recent updates...for 2013-14



9.9.14 HRR688 Ignition Kit and FBO Custom Curved Distributor

Hey Don, All I can say about the stuff you sent me is, Wow. That truck must have been running on 6 cylinders because now that thing is banging on all 8 for sure now. She runs through first pretty fast and second is leaving a shingle in the road and third she just don't know when to stop haha. I really appreciate the technical help and the products I received. The installation went flawless and she runs better than ever.

Thanks, Travis




Hi Don,

I remember you requested I send pictures of my new engine after I installed the new distributor and Q850 carburetor.

The engine is a 427 small block stroker.

The engine runs like a real beast. The spark plugs all look great.

Your loyal customer,

 Jay Attwood





I will hook it up to the constant vacuum port on the intake manifold where the booster is connected!

If you didn't gave me advise on this matter I could have ruined the I have to thank you for this you are a lifesaver!!

In Holland the USA cars are serviced by people who don't care about the little details if it runs ok it's fine but in the long run the over advancing of the wrong vacuum port could destroy the engine....I did visit a local USA garage and tuned it but after that session the motor did run like crap so I ended up with FBO and now the problems are over!!

Thank you many times!!!!!!!!! You have learned me a lot about the basics of timing, for a lot of people this is hocus pocus!

Regards Dennis





Hi Don,

Thanks again for all your help. I was so frustrated with the way my 1967 440 hp ran ever since I put it to together with an  electronic conversion about 6 years ago, It didn't seem to have the performance it should have had.  Rebuilding & re-jetting the carb just made things worse.  After talking with you, Having you guys set up my distributor properly, And replacing the original points style voltage regulator with your VR-1 regulator, It`s like a whole new car! It idles now,  and WOW it really moves..... And uses less gas. A real plus at PREMIUM prices. I actually love driving it again. I will be recommending this distributor service to all our customers at Graveyard Carz.

Yours truly

Royal Yoakum

Restoration Technician at

Graveyard Carz


Check out Graveyard Carz on Velocity TV


6.3.13 Unleashing the Potential


Hey Don,

So here's how it went yesterday, we installed the distributor and timed it at home per your instructions. Ran way better no more eye burning tailpipes all around it felt better at cruise and playing a little on the freeway.

We made one pass still with orange box and it ran 12.17 at 94 MPH previous best was 12.19 at 92 MPH.  Then we installed the HRR box, it ran 11.94 with no other changes. It pulled hard all the way down track i could feel the improvement in the seat of my pants. Yee Haw! after 5 years we got into the 11's!  We base lined the Q750 at home as per your book, we then bolted on the carb just as delivered no internal changes other than the Air bleeds you sent, we followed your guide and adjusted the idle speed and 1/4 turn on the AF mix screws and it smoothed right out.

Last test run for the day it ran 11.78 at 101 MPH!!!!!!!!!

we were all doing the happy dance, best money i've ever spent on this car

First round i screwed up with a red light but it ran 11.80 at 101 again doesn't matter I can't tell you how pleased I am!

Driving home from the track fuel mileage check it picked up 4 miles per gallon from 9 to 13 after all changes, 115 miles each way 230 miles I'll say we'll now save 9 gallons of premium at $5 per gallon $45.00 IN ONE ROUND TRIP!  just going to the race track the rest of the year we will save over 1/2 of what we spent and with all the other driving we do with it my return on investment will come by seasons end, it like getting 50-75 HP for free! and yes my wife WILL now ride in the car with me LOL


Jay W.


This is a 440 in a Dart, .... Jay it was always there we just needed to unleash the potential power.  We really appreciate you taking the time and effort to go through this on track test with us. Sorry about the wife thing..... :-)






Hey Don, this is Bud You have been helping me with my Dads Hemi 426. I just wanted to send you an email and pictures. I love the new ignition box and coil. I will be ordering one also for my car soon!


Stress Test:

Made In China Orange Box Vs. Made In USA Orange Vice... Vice 1 - Orange Box 0




A big thumbs up for the HRR688 Ignition Box






Calvert 90/10 Front Drag Shocks


They did the trick.  I went to Yakima with a couple of heavy hitters from Woodburn and went out in the 4th round on Saturday.  The good news is that my 60 ft. varied only .009 from high to low.  1.650 to 1.659 out of 10 launches




Hello Don,

Just a note to say thank you for your guidance and advice over the last few years. I tune my car always referring to your guide and have purchased from you quality components that have again been a major contributor to winning performances. Over the last two drag racing seasons I have purchased from FBO, CalTracs Suspension, FBO Fuel system, FBO distributor, and Slayer carb components. In 2012 I won the NZDRA Super Street National Championship and National Meeting. This season (2013) we moved up to Super Sedan and won NZDRA National title with our super consistent car! Thanks again for all of your advice and tuning secrets!


Taupo, New Zealand






I got everything buttoned back up in the charger. WHOA! What a difference switching to the vacuum advance! NO hesitation....smooth power across the board once I got the timing right. Honestly it's never run this well. I'm thrilled to get rid of that dumb ballast resistor as well!  Thanks for taking care of everything for me, and for throwing that tuning guide in. I had one from you years ago and it was a little beat up from being around the garage. Very much looking forward to getting this carb set up right, which it never has been! Thanks again!

I'm sure I'll be in touch! -Pat




I've recently ordered and received 2 or your products and gotten tech info. by phone.  I just wanted to let you know that your service and support are FIRST RATE!  The 2 products ordered were received the next day.   I'm telling all my racing buddies about your company.







From our instant Chat 6.23.10

12:57:17 PM [Don] Hello
1:00:44 PM [Bill] Thanks Don. Awhile back I sent you my distributor for a re-curve. It was for my 66 Chrysler 300 if you might recall? I just wanted to say that what you did for me is absolutely awesome. The re-curve and the associated parts I purchased from you have given new life to my ride. No more rich smell and bogging at initial acceleration. I am still using the Edelbrock 750 at present but as soon as the funds loosen up I will get that speed demon 650 you suggested in its place. Again thanks....
1:02:06 PM [Don]

You are most welcome!!!

1:02:26 PM [Don] We appreciate you taking the time to call us and hopefully you'll tell your friends
1:04:12 PM [Bill] I just cannot believe how nice the car runs. It's as if it is brand new. And all that I needed to do was get the re-curve, your ECU, Ballast, and Coil, hook everything back up, adjust a little timing and mixture, and voila...runs great. Now if we could just get these storms down here in Northwest Florida to stop, I would drive it more...

1:04:29 PM [Bill] We will do more business real soon...Bill


Don & Staff

Just wanted to say thanks for all your help with my carb and timing problems Chevy V-8 327-750 Holly DP mech..

Even though I purchased only a couple of small items from you never once did you turn me away with all the numerous calls I made.

You and your staff were always on the money with getting my problems resolved. There are not too many people like yourself left that will take their time and offer help to us car enthusiasts unless we are spending a lot of money, my hats off to you sir.

Furthermore if at the time you could not speak to me you would return my call…WOW! At first I thought I’ll never get a call back but low and behold you did call back.

In closing if you or your staff ever get down to Atlantic City, NJ please feel free to call on me as you will always have a friend here.


                                                                                    Kevin R Mc

Thanks Kevin, you never know you may have a visitor some day-Don




Hi Don,

It's Chuck here in Illinois with that 65 Cuda, and the 273 with the Isky cam - we've been discussing the vac pot, a possible ReCurve, etc... 

If there is a testimonial page, this is a story that belongs there... 

I bought the A688 kit 3 years ago, rebuilt the stock 273 a year ago, and have not had the valve covers off since I warmed up the motor for the first time, and set the valve lash on the new mechanical cam.  After a year of fighting poor performance, unaware of my error, I called you and talked about the low vacuum, and that I checked everywhere, and can't find a leak.  You refused to take my money, to get a ReCurve on the distributor, and a new vac pot to activate at lower vacuum.  You said you would not take my money, because you knew there was some other issue, and there is no reason why my little 273, even with a .425 lift, 260 dur. cam would not pull at least 16" vacuum....  You were right !!!    I pulled the valve covers and found my bonehead screw up.  When I put the heads back together, and set the valve lash, I had set them to .013 ALL VALVES, intake AND exhaust.  When I warmed up the motor for the first time, I checked and they were all still at .013, so I left it...  I WAS HOLDING OPEN THE EXHAUST VALVES SLIGHTLY the whole time since a year ago, which is why I could not build vacuum, which is why my advance pot would not work, which is why my mileage and performance stunk, etc, etc, etc...  Proper setting is .013" for INTAKE and .021" hot lash for EXHAUST...

 I was getting 12.5" vac and running extremely rich, and as soon as I reset the hot lash, and put it all back together, the first turn of the key I had 16" of vac, and had to turn everything DOWN...  I went to a steady idle of 900 rpm, disconnected the pot, set initial advance at 17-18 degrees, leaned the idle screws down to 1.5 turns open (they had been open all the way), and then reconnected the vac pot, and 13 degrees came right in...  After adjusting timing and idle screws, I now have a crisp idle at 950 rpm, with 16.5 - 17 vacuum...

 THANK YOU for taking the time, despite not having a sale in 2 1/2 years, thank you for sticking to your guns that there was a different problem and I had to find that first, and thank you for your HONESTY, and not just booking a sale, when you could have...  It's like my motor woke up from a bad hibernation, and now it pulls like crazy, and is a ton quicker, especially in the mid range...  I finally feel like it is running at it's potential, and that's a great feeling... 

Best Regards, 


Reply:  It's just the way we do business.




 I thought I knew what I was doing with regards to tuning and setting the timing. I bought your book and after reading it, It was eye opening experience on tuning this carburetor and setting the timing and it also gave me tips on racing and the tricks people would do that I did not even realize. so since I got the book the car is running consistent and I have won some rounds not a whole event but I am sure it will happen. 

Thanks and I do recommend the book.





Some great news for you, this year was a tremendous year for me and my 1967 Dodge Coronet with a stroked 431, as I became the Sportsman track champion at Western Colorado Dragway.  I have purchased from you the FBO Ignition kit, the FBO Ported mechanical fuel pump, a Mighty Demon 750 ETS  and a complete Cal-Trac system, including mono-springs, front and rear shocks.  Of course I was given your Tuning to Win book.  This was my third season and after two years of hard work and your help everything came together.  I started off the season winning the first three events in the sportsman class, followed by winning the Mopar only class special and taking a second in the fourth race.  From there I had another win, two more seconds and a couple of semi-finals.  With your help and the FBO products that I have purchased from you over the years has propelled me to where I am today.  The last change that was made to the car was the Cal-Tracs system.  What a difference that has made in consistent launches, you can even see the tires wrinkling upon initial hit.  In fact during a test and tune session I took my father-in-law down the track with me.  What made that so special is that when I hit the throttle he almost fell over the bench seat in the car.  You should have seen the smile on his face after the run, he is a die hard Mopar man and is the one responsible for getting me hooked on Mopars and drag racing in general.  So I can not tell you enough how much I have appreciated your hours of time, comments, coaching and suggestions over these past couple of years.  In fact I even have a fellow Mopar guy working with you now too.

Thanks for Everything.

Daryl D.

Track Champion


9-27-2008 from a hand written letter verbatim:

Don & Staff

Just wanted to say thanks for all your help with my carb & timing problems.  Chevy V-8  327  750 Holley DP Mechanical. 

Even though I purchased a couple of small items from you, never once did turn me away with all the numerous calls I made. 

You and your staff were always on the money with getting my problems resolved.  There are not to many people like yourself left that will take their time and offer help to us car enthusiasts unless we are spending a lot of money, my hats off to you sir. 

Furthermore if at the time you could not speak to me you would return my call…WOW!

At first I thought I’ll never get a call back but low & behold you did call back. 

In closing if you or your staff ever get down to Atlantic City, NJ please feel free to call on me as you will always have a friend here. 



Sept 08

I hate you and I love you, everything you told me was right on, I screwed up and it's hard to admit sometimes that I'm not as smart as I think I am.  I bought your 850 ETS carb and you were right I went .2 faster.  Then you curved my distributor and I went another .1 quicker. Your spacer plate and careful plug reading and it went 9.98.  So here's the hate part, now I have to spend $3k to make it and me legal for NHRA.Thanks, I'm really having a blast and you were right I do have a 9second Mustang.

Brandon in Ks.




November 2007


This may in fact be your first testimonial from someone who has not purchased a single item from you (yet). I just wanted to take the time to say thank you and put my 2 cents in to anyone thinking about doing business with FBO. Yesterday I emailed you my spec sheet along with a relatively long winded paragraph venting about how the 340 in my Dart was performing below it's potential at 1:44pm EST. Now I was thinking to myself. "I'll email this sheet, someone may or may not check that email today and may or may not call me back but it's worth a shot..." I honestly didn't believe it when at 3:29pm EST (just 1hr 45min later) I received an email back stating you thought you knew what my problem was and you were going to call me! Sure enough at 3:31pm EST I received a call on my way home from work and you spent about 45min on the phone with me (in the middle of your busy day) troubleshooting my issue and by the time we were done I had a clear path before me on how to proceed to correct my 340's lackluster performance and an offer (actually more of a request!) from you to call you back as soon as I had made a few changes so we could proceed to get my car on the right track. All this without a single dime changing hands whatsoever. I was sold after reading the plethora of tech info you've posted on the website and filling out my sheet hoping, sending it and hoping for the best. Now after experiencing the level of customer service you extended to me before I was even technically a customer, I'm sold for good. Thank you again, now I have to get out to the garage and get to work. My order for the correct coil and ballast resistor are coming...

Brian Kraegel
Kalamazoo, MI



Hi, I got a copy of your book on demon carbs it is by far the best book on carbs that I have read.

Thanks Jon Wilson



I recently purchased your book Tuning to Win and have done a lot of reading on your website.  The information is truly amazing and I have learned a ton.  Thank you for providing so much help to us Mopar guys.


Best Regards,



May 2006


Hi Don,

The HEI distributor works beautifully. I'm at 16* initial with no more

part- throttle ping, it'll idle respectably, and has reasonably good

throttle response right out of the box!

I think I could use a little more stall in the converter but it's very

drivable now. Good work.

Thanks for a very positive outcome after a long struggle. I'll call you

again when I've stashed enough lunch money to upgrade to your Demon carb

package and really get it going.

Thanks again,

Happy Dave



Got the guide a few minutes after I spoke to you. I've only read the

first half. But, I can already tell I'm in for a real education. When

it comes to carb tuning, I'm a complete novice. However, you've made it

straight forward enough that even I can understand it. Being an

engineer, I appreciate your explanation of the physics behind all of the

car's components. It helps explain the reason behind the adjustments.

Thanks for all the time you put into this. You've definitely won me

over as a customer 


April 2006

hey Big D

For 4years now I've been picking your brain and every single time you hit the nail right on the head, you've taken my piece of crap car to level of perfection to rival an Indy car. everything is as perfect as you promised. i made a copy of your book for a friend so I just Paypaled you the $10.

Come to NY and the beers are on me.


Just a quick note, got your ignition installed w/ a new set of plugs and have driven it quite a bit the last couple weeks and just wanted to say my car runs a 100% better!!!  It starts quicker, idles much better and is a ton more responsive.  Now I need to save my pennies and nickels for that new Demon!
Thanks a lot, 



I currently have installed your Stage 2 ignition kit in my 340 Mopar.

The kit solved a 2-year old idle problem for me and I could not be

happier. You made me a believer!!!

Now I would also like your tuning book.



Thanks for yet again great service! I have dealt with a lot of vendors

in my car hobby and I will have to say, you are the best.... Very, very

friendly and very punctual... This is not very common in today's world.

For that I thank you!!!!

I am going to fill out a data sheet for a Demon Carb and send to you for

some recommendations..... So look for it in a day or so.



March 2006

Where do I send the money?

My mechanic charged me $370.00 and couldn't make my car run worth a d*m, told me my motor was no good.  I bought your book for $10.00, had you curve my distributor for $69.00 and it runs like a Swiss watch!  I took the car back to his boss and we went for a ride, he read your chapter on ignition tuning and refunded me all the labor back $300.00!!!  So I figure I owe you at least 1/2, he wanted a copy of the book, I gave him your email address....charge him $100.00 he deserves it.

January 2006

I assume you have received my $10 payment? I have the blue covered "Demon tuning guide" book and I have to say I consider that to be almost worthless compared to the information in your guide.

I went through your tuning guide and adjusted the carb based on your info.

The car idles great and I hit the gas and its a crisp response.

Again, the guide is awesome. Every demon owner should have it!

Dan/67 Cuda-360

October 2005

You should be proud of your reputation and satisfied customers. Must be doing something right......Hope you have a good holiday, and thanks for your honesty.

I just wanted to say thanks for getting me the head gaskets I needed in a hurry they got here Thursday a day early, your customer service is GREAT. I'm the one who needed the 4.125x.040 SB head gaskets
Thanks again Larry G.

August 2005

Installed the stage II distributor this morning in my 340 Challenger.  And all I can
say is WOW  !!!!!
Talk about a huge difference. 
Thank You.
Bowie, MD

408 SB Stroker Cobra- Portland Oregon
Remove a 850 and install a 650 Mighty Demon, re-curve distributor, problem solved, clean idle, instant throttle response.  All issues gone!
"I had no idea this car had that much power lurking under the hood, I was disappointed in the engine I chose until you fixed it!....I'm now a very happy Cobra owner."

JULY 2005

427 Cobra-Russ from Hillsboro Oregon
650 Mighty Demon Installation and distributor re-curve

You couldn't have chiseled the grin off this guy's face with a Jack Hammer, he finally got to drive his car without fighting it down  every inch of the road.

May 2005

I received the 650 Speed Demon and the recurved distributor.  It took me a while to get the grin off my face from the much improved throttle response…no hesitation…it pulls strong in every gear ( I didn't get into 5th, yet)…it shuts off without dieseling…and it can even spin the tires now without much difficulty.  It's like a completely different vehicle.

Havn't touched a setting on the carburetor at all.  It idled great right out of the box.  There may be some fine tuning to do, yet, but I'd like a little more time and new spark plugs to make sure before inquiring too much.

Also, the distributor recurving is great.  I didn't realize that the couple of degree bouncing behavior that it used to do was not normal.  It is now rock solid and stops dead at 15deg advance from initial.  The housing ear is limiting me to 19deg initial when it hits the temp sensor in the manifold, so I will be doing some modifications to allow me to get to 20deg initial.

Hello Big daddy
Why didn't the Holley and Barry Grant tech people tell me this stuff  I've struggled for 2 years trying to make this car run right, tried 3 different carbs and 2 so called performance distributors ($2100.00 total spent).  I read the book, made the adjustments and it's perfect!!!!!!!!!!!!! all issues are solved for with a  $10 Book, $20 Bushing kit, 2 hours of reading and 20 minutes under the hood.

I'm not a mechanic by any means but after reading this book I feel like I'm a professional tuner...just awesome!

Thank Al Gore for the Internet *Laugh* I love my car again


, this tuning guide is amazing! best 10 bucks i've ever spent on my car.

Thanks very much for all your help and extremely reasonable prices.  I added a little to offset the Paypal fees.  Can't wait to get the engine dolly, and look forward to dealing with you again.
PS:  the tuning guide is fascinating and will be of great help!

April 2005

From the Club Cobra Forum:

Recently, I had the pleasure to do business with Don Gould who is the proprietor of FBO systems. FBO specializes in Barry Grant's Demon Carburetors among many other products.

Don was very helpful by working with me on a suitable configuration and replacement for my 13 year old Holley 850 double pumper on my 428 FE.

Don took all of my engines specs (Cam, heads, intake, feet above sea level, etc) and suggested the "correct" Mighty Demon for my application. Being fully versed in Cobra replicas, he was aware of my turkey pan cold air box arrangement, and provided the correct gaskets and AN fuel line couplings (I provided him a digital picture of my current plumbing to assist).

Once I ordered the Mighty Demon, Don performed his magic by inspecting the carb via a tear down and testing it and adjusting the carb to my engine's specs.

Within one week the Demon arrived. Installation was fairly straight forward with only one glitch. A minor 1/32" adjustment to the turkey pan needed to be made to allow linkage clearance.
The AN fittings supplied were a perfect fit.

The Mighty Demon 750 has three minor differences from the Holley. First is that the center post is 5/16" which is a bit larger than the Holley 1/4" center post. The center post holds the air cleaner on.

Second difference is that the Demon takes different fuel line fittings than the Holley... Don provided these.

The third difference is that the Mighty Demon has TWO idle speed adjustment screws, one on each side of the carb whereas the Holley had just one.

To sum up, the carb is beautiful and frankly makes my engine feel totally different and much more responsive. I am still fine tuning the idle speed.

I highly recommend FBO and Don Gould and the Mighty Demon double pumper.

Hey Don,

  Well the Chevy keeps on getting better with the fine tuning help from you! I took the car to Bremerton Raceway this past weekend I did the test and tune Saturday and raced Sunday. I went four rounds before I FELL a SLEEP on the light….. The Street Car Ran A 11.79 @ 114 and my 60’ was 1.62 not bad for a 4000 pound PIG. Some even said the Drivers front had Day light under it. (It felt like it did but I want to see a picture first) Any way just wanted to update you on the Car…. The Demon and your four hole spacer are working very good for me! Thanks for all your Help!!!! Mike

March 2005
Hi Don, 
You convinced me to go with the 650 Demon in place of my 750 Holley on the Roush 427 in a Superformance Cobra, thanks. 
Have put 1500 miles on it and it performs as you said it would.  Have turned a few screws but back to nearly the original settings, good job.  Just got back from the Texas Cobra Spring Fling at Round Rock Texas, about 85 cars there. 

The other Superformance guys were impressed with the overall performance with your carb, what little I lost on the big end (if any) I more than gained back in driveability and bottom end performance.  Two of the other Superformance cars had the same Roush 427 with the 750 Holley's, I gave them your website, I'm sure they will be calling.
One problem.  I have messed with the timing at idle.  Like you said it likes 22 deg.  Roush wants me to stay 35 deg (or below) total.  I need a bushing that will give me 12 deg. in the distributor. (I will stay with a 34 deg. total)  MSD says they can't help me, they don't make that bushing.  You know of anyone I can order from??
Thanks again, the carb has done all you said it would - - - happy customer.

Bushing kits are available from none Other Than ....FBO Systems  $19.95 set of 3, 16-14-12 total advance.

Hey Don,

Well I took the old Chevelle to Seattle this past weekend and I finally got my 11 second time slip!
It ran an 11.986 and an 11.99.
 Any way I thought you might like to hear I lost to a MOPAR that was dialed a 11.08 and ran a 11.09 It was a real good race though I ran right on my dial (11.99)  My car also 60ft’ed 1.68 which is the quickest ever for the 3900 lbs. pig. All in all not bad for driving the car 5 hours, racing it and driving it home!!!!
I used your Tuning guide to make the jet changes and it was right on!
I can't believe the difference between the old Holley and this Demon, awesome, thanks


Hello Don,

The car is incredible, no bogs or surges, instant throttle
response, the Demon carb and your Ignition really woke this motor up, timing
is set at 18 initial, starts right up and idles, even when its warm, it
starts right back up, but I do have one new problem, TRACTION, but we will work
on that another time. I am very impressed with the 575 Demon, stomp it to
the floor and hold on, can't wait to take it to the track, what would I have
to do to become a dealer for you!

Randy, IlL

February 2005

I took your advice contrary to what my engine builder said and bolted on my friend Frank's 750 Mighty Demon , which is a carb that you sold him and set up.  He's about 2-3 weeks away from needing it so I thought I'd give it a try. I wanted to see for myself who knows tuning and who's just full of BS.

We took off the custom tuned and modified 850 Holley with a 2" open spacer and bolted the 750 Mighty Demon down with your 1/2" 4 hole spacer kit (NICE Gaskets!) and installed the FBO Coil and ECU kit. It fired right off and idled at 1050, exactly where you set it for Frank's motor, how do you do that? Set what? We didn't even touch the idle screws it ran and idled like it came out of a super tuners shop.

Old best time 12.39, first pass was a 12.02, we adjusted the launch RPM and tire pressure and it went 11.97, scared me when it launched. We moved the timing to 22* at idle and installed the 12* MSD bushing you made for me, it idled even better! If that's possible, the throttle response on this 440 is unbelievable, I did have to bring the idle down from 1275 after the timing change....check this out..It Ran11.92!
That's a 1/2 second faster than it has ever run!

We made 3 rounds 11.94, another 11.92 and 11.932 (broke out on a 11.94 dial) I know, if I had of read the tuning guide you sent Frank more closely I would have dialed a 11.91.  I have never had that many runs so consistent., unbelievable consistency!

The plugs look perfect (pic attached) and it ran cooler than normal, started so quick you couldn't hear the starter even engage.

Yesterday I called the engine builder and gave him the results of the smaller and WAY CHEAPER carb with your CORRECT timing numbers in the motor....his comment  "He must be modifying those carbs, I've never seen any Demon work properly and where did he get those stupid timing numbers from? You need at least 36* in that motor"

It was all I could do to refrain from calling him and idiot and hanging up on him.  I asked him if he would like to buy his perfect 850 Holley ($659.00 plus $350.00 for his modifications) and the orange box that he sold me  ($79.00),  he didn't find that funny at all and again claimed that you must have done some secret hocus pocus modifying of the carb and if he had the opportunity to tune it he could make the Holley outperform the Demon in 2 passes, I reminded him that he had been to the track with me on 3 occasions over 2 years and charged me nearly $400 in parts and labor to "Tune it"...he made a very derogatory remark directed at me and you something to do with intelligence and sex and hung up?...Guess I need to find a new engine builder, I don't think I'll have to look far, I have your number on speed dial.

You got me to the 11's when no body else could over 2 years and probably $2000 of dyno tuning and carb modifications, everyone told me I needed more motor, more cam, more carburetor, more this, more that, more, more and you did it with LESS!

So Frank needs a new 750 Mighty Demon, no way is he getting that one off my engine, you have my CC info on file please ship direct to Frank.
He wants it set up exactly the same way, do you take trade in's? I have a ugly old 850  Holley I'd like to get out of my sight.  If I can sell it I'll be ordering those Racer Brown rocker are the Guru!

Well I will admit I do some very tricky Hocus Pocus Voodoo stuff to those Mighty Demons, I take them out of the box, baseline adjust and check them to be sure everything is correct.  Then I wave a burlap bag of Hair of Goat, frogs toenails and chicken lips over the top of the air horn, mumble some words I learned from a good looking Cajun Girl late one night at the Rampart Hotel in New Orleans, finish off by letting
Duke the Big Red Shop Dog  give it a big slurp on the secondary float bowl and it's ready to go.

Tell Frank his carbs on the way.....I'll have Duke give it a double slurp, he has no shortage of tongue



January 2005

Hey there,
Just wanted to write and say thanks, in regards to the electronic voltage regulator.  My Mom ended up ordering one for me.  Anyways we got the part a couple of days ago, put it in and it works perfectly. It's definately nice to be able to use the Barracuda again after a month of dealing with problems.
I'll definately recommend you guys to my friends if they have similar problems .
Once again, just wanted to take some time to say thanks for offering such an awesome part, especially after dealing with 3 mechanical regulators popping on me.
-ken k.

November 2004

I now agree with you on that choke thing, your distributor and carb set up was flawless!

Cold weather performance:
 We had a few brisk mornings with temps in the mid 30s and below freezing over night. At 6am, I head off to work and
every morning this thing fires quick and runs beautifully. I've never had that before, even with the DFI I tried.

October 2004

1970 Ford Torino-Vancouver Washington
Went to the track  yesterday - had a good day including  winning a couple of rounds  - good air!
After your last work on my car, 60 foot best is1.991 with an average 2.030, 1/8 best is 8.884 with an average of 8.948, 1/4 best is now 13.927 with an avg of 14.038, and top speed has been 97.11 with an avg of 96.29. Improvements are .339 quicker in 60 feet, 1.047 quicker in the 1/8, and 1.371 in the 1/4. Old top speed was about 93.2.
A little math to compliment your efforts!!
Weighed my car - car and driver 3830.

This is a stock short block with cast pistons....351W, we ported the DOOZ heads, Racer Brown Hydraulic Cam, Dynamic Convertor.
Turn around time,  parts and installation 6 days.....another happy customer :-))

Hey Don...We Won :-))
Your 360 beat up on my Buddy's 451, no problem.
We made 3 passes and even though I was desperate for traction it hooked up in time to smoke that 451 stroker..Happy dance!

Next year we'll work on the traction problems but I just can't see this Dart being able wear a big enough tire to hold the tork of that motor
Awesome thanks!

Hello, my name is Ol' Rock. I'm a 1972 K5 Blazer from Aggieland, USA
and this is my story...

I found a new home 8 years ago with a 17yr old high school kid from Mansfield, Texas. I was a little scared, but then realized this kid
acknowledged my joints were old and I didn't have the spring in my step to keep up with all the youngsters around me. I received a few
bandaids, but these were only temporary fixes until real surgery could be afforded. In 2001 I received a transplant...a new GM crate engine -
a 330HP 350. This was great! I was running better than I had in years and we were both so happy. I would still cough and spit up a little in
my mouth early in the morning. A bit of uncontrollable backfiring wasn't was so embarrassing! My owner tried throwing more
heat at me through a MSD 6A ignition box and a Mallory unilite. That helped a little. I was drinking too much and just never could get
enough air to get going like I really should. Next we tried new mouths... we went from a Holley 2B Digital injection system to a Carter
AFB. Finally, we went to a specialist to find out why I never could run as fast as I should and why I was coughing up through my Carter and why no amount of tuning would smooth out my stride.

Dr. Don Gould of FBO Systems had a few suggestions. As it turns out, I was spinning to tall of gears to get going off the line, and my little
crate motor couldn't get pumping in the power band before getting bogged. First step...install a Dynamic Converter with a 2800 stall
speed. This would allow my little bowtie heart to beat a little faster for a better start. Stupendous! A little physical exertion test
revealed the crate motor wasn't tuned for best performance from GM.  Instead, a little marketing was used to sell a old technology, muscle car era camshaft in this power plant.

Racer Brown supplied a new camshaft specifically ground for these 330HP heart with Vortec heads. Now, we needed to work on my nerve firing, breathing and drinking problem. A new MSD HEI was recurved and phased for accurate timing and energy
delivery regardless of whether I was standing still or all out sprinting. A BG Speed Demon was custom jetted and handled my lungs and
gave me accurate doses of go juice right when I needed it. To make sure my thirst was quenched while going full banshee, a BG pump with braided lines was installed next. After hours of assembly, a little bleeding and a lot of praying, I was ready for my first steps!

WOW! Response is absolutely incredible. I can jump off the line and spin my 33" BFGs if I'm not carefull (3:08 gears, TH350 trans) and I
can run with the best of 'em now. The makeover is truly amazing. I'm a little on the heavy side (4 wheel drive with NP205 and steel skin
inside and out), but I'm easily outrunning the youngsters around me.

Scalded dogs can't keep up with me! What's really great, is that I can sit idle without shaking, and start all out screaming with immediate
response. I'm calling June 1, 2004 my Re-Birthday. It's amazing what someone who knows what they're doing can do to help you. Follow ups
were great, and phone counseling was always welcomed. I'll be calling to say thanks as soon as I can stop smiling and move my mouth again.

Gig'em Don!
'Ol Rock - 1972 Chevy K5 Blazer
Clint- Driver
Aggieland, USA

Disclaimer: Don Gould is not really a doctor, although his ability to cure my ills without seeing me is remarkable.
No animals were harmed during product testing.

Quick Specs:
previous setup:
GM350 330HP crate motor
Mallory Unilite Distributor
MSD 6A Ignition
Hooker Competition Headers
GM TH350 Transmission (stock gears)
GM 12-bolt rearend with 3:08 gears
BFG 33" All Terrain tires

What's New:
Racer Brown custom camshaft for 330HP GM crate motor (lifters included)
MSD Pro Billet HEI - recurved and phase aligned for precision
Dynamic Conveter - 2800rpm stall
BG Speed Demon 650 CFM carb with Mech Secondaries
BG High Flow Mechanical Fuel Pump
SS Braided Fuel line from pump to carb with dual feed.

Great Story Clint, Give Ol' Rock a Kick on the Loud Peddle for me!

September 2004

Hey DON,
Last night at the track i pulled a new best ET and MPH.
last year my cuda went 11.87 115mph and last night i went 11.67 116.21 mph!!!! Had a new best 60ft time also at 1.65.

I guess he likes his new FBO Ignition kit  :-))

" I must admit that I became frustrated with this, and in desperation, replaced the Holley with a BG Speed Demon. What an improvement! The engine even sounded better. And my eyes weren't burning anymore. I'll never put another Holley on a Hi Po engine again."

...another Happy Demon Carb Owner!

Man!, the car runs great. I know there is more tuning to do, but at least it is drivable and
has a very cool idle. The timing was checked again and it is at exactly 36 degrees total. I just wanted to
say thanks for all the help and great parts. I will be calling you in the future and sending my friends in
your direction.  (See this Cobra in the Customer ride section)

May 2004

"Take off that Eddy 750 and put a real carb on it then get that distributor curved......."

...................2 weeks later.......  :-))

 I Drove my Car to work Yesterday and had three friends in it and It spun the tires until 3rd gear, Usually just got a good second gear chirp.....
going to the track on Saturday


Email Discussion with customer............

You may need a 4.5 P/V but I'm still not sure if you don't have other issues, the RPM drop is way high, my car drops from 1500 to 1200.
Have you checked for a vacuum leak?

You are very good!!!!!! I was messing with the car last night after work and low and be hold My power break booster line that is plumbed right to the manifold was off completely!!!!!!  I will double check every thing with the vacuum line all hooked up and just start over with the adjustments.
Thanks for keeping in touch I am glad I bought from you I think Summit would have just sent me a sticker and took my money!

Thank You for your support, we work hard to "EARN" our Customers loyalty.
It pays to support your Independent Performance may need them one day....

From a message board:

From another forum (MoparChat) the DUI system got slammed. Very unreliable apparently. Another company, FBO systems, was named as one that has a similar offering but is much better. Many, many folks were glowing with praise about FBO. Almost seemed unanimous in their praise. Works for me!

1969 RoadRunner 440 6Pak

April 2004

Hello Don,
We purchased a King Demon RS from you last fall (got it after meeting up with you at Indy Show in January at Smokey Bones!).  '63 Polara tube car had run a best of 9.72/134.  Bolted on the new King Demon, ran 9.44/137.  1.60' went from 1.38 to 1.29
Bloomington, Illinois

    I finally got the chance to get my car on the road. It is an awesome pulling machine. It has power all the way from idle to above 5500 RPM
 where I shifted it. My wife was in the car and when I just shifted into 3rd she told me to slow down. I didn't... I told here I still had a gear to go!!!!! :) I got called a name that I don't know if I can e-mail to you. :) She didn't like the continual hard pulling of the car. She drives a new Beetle so I guess we'll give her some slack. LOL

That is of course except I now may have to go and see my doctor and have my nose removed from the inside of the back of my head. LOL
Ya da man Don!!!!!!!!

(This is one of our 400HP 360 Crate engines, Hydraulic Cam, Pump Gas, Smogger heads)

Hello Don, I just wanted to let you know I got to try the coil this past weekend, did some t&t with it, and my other
one, and I will have to say I was kinda surprised, your coil was .03 quicker than my other one, guess which one will stay
on the car.


March 2004


I changed the power valve like you suggested (it seemed to
accelerate a little smoother, feels like its almost like it was
when it was EFI).  Then I added the 4* initial timing, then I did one more
full throttle run, and the plugs are light tan, no popping at all, and it seems to have all its power back like it
did before.

Thanks for all your help!!!

Don, I'll work on that total timing, it will probably be a couple more weeks before I can take her around the block, but it sure feels good to have the idle problem behind me! I can't thank you enough, but I can assure you that in the future, when I'm in the need for performance parts, the phone to your order desk will be ringing! 

I'll make sure that my Cobra friends have your number when they are ready to shop.Yes, I can surely now see the difference between talking to the guy behind the counter at the local parts shop, and talking to the guy who really know his chit!!            
Thanks a million!!! 

Original Question:
Hey there..I'm hoping you can help..even though I'm a Chevy guy..I need a new Demon carb,and want to get the right one.

Final response:
Thanks for all your help, you have a permanent place in my address book..It's hard to find people who have a genuine interest in helping others,especially when this is not just a's a passion!!....Thanks again


2003 Testimonials
Hello Don,
 I would like to take a moment of your time today to thank you very much for your help and assistance in helping me get my truck running like it should.

 As I'm sure you may will recall I purchased a new crate motor, 330hp/350cid deluxe engine which came with a 600 Holley.After I gave in to the fact that I couldn't get it running anywhere near it's ability I went on-line to find help.

 After finding your web site and reading about Demon carbs and reading your statement about your help in resolving problems and tuning help I must admit I really didn't believe it.

How wrong I was!

 I did purchase a carb "625 " and had my distributor phased and curved, once I received the products and installed them I thought I had a different truck but most of all I was truly surprised and amazed at the amount of time you spent with me on the phone helping me resolve my problems. I work in the manufacturing sector "injection molding" as a maintenance manager which requires me to do business with many vendors and I must say they could all learn from you as to what the word service really means.

 Most of all I love my truck now and it runs like it should thanks to you.

Marshall Anderson
Burlington N. Carolina


Don, Thank you so much for all your help in getting this Demon tuned
properly. You spent quite an amount of time with me trying to troubleshoot
it over the phone. We made a Road Demon perform like a race carb. I know
this is a difficult task since the ear is a very good judge sometimes. All
issues were covered and addressed and repaired. I'm one happy camper. Yes I
did have an obvious problem that I did not find until later in the tuning
process, but all is well and my TRUCK? is running well.
81 short and wide with a new 355 sbc. It's been 30+ years since I've done
this type of toy and Don refreshed my memory on quite a few things.
Thanks again for all your help. I didn't buy the carb from Don nor even
thought of using it on this machine, but Don helped me to get it right.


Hey Don,

Got the Cuda running.
I was able to get a high rise throttle bracket from XXXXXX  so I  was able to keep the 1 inch spacer on there.

WOW what a difference.
I haven't even really gotten on the car yet but 3 things stand out.

1-Ice cold it starts right up.

2-After setting only the idle speed it has 15 inches of vacuum almost steady.
The best I could do before was about 12 - 14 very wavy.

3- I only took it around the block because of rain but NO OFF THE IDLE STUMBLE!!.

I could never get rid of that and I usually had to ride the clutch a bit.
At  idle I have 20 degrees and I have 34 degrees total.
Also on both front and rear sight glasses the level is almost exactly in the middle.
Pretty Cool.
I'll keep ya posted

Hello Don,
 Hey Don,

Just had to pass along a note of "THANKS" for your help. Wayne and I got our carbs in and tuned yesterday and they run great! What a difference! For the tuning portion, we both ended up with 5/8 of a turn out on the mixture screws to achieve max vacuum at a constant RPM.


Got the Challenger running last weekend and it runs awesome! That Demon is a breeze to tune compared to the Holley or the Edelbrock.  I do need a bigger fuel pump but that will be a week or so 'till I can get to that and I won't be driving the car too much for now anyway.


I used your knowledge on the carbs and plug reading to whip up some black magic on my two barrel 318 wow what a difference!! I just figured the tranny couldn’t handle all those horses at once ha ha. I'm going to check it out in a few minutes I hope your right.

Thanks for the help.

I called him on a Sunday and we ended up speaking 3 times that day. The bottom line is that before my first call, I could not get around the block without two footing it to keep it running. After my last call that day, she was purring like a kitten. I am sending my distributor to him for recurving and testing and I am sure it will run even better when I get it back. He did not just tell me "do this" or "do that," he took the time to explain why. Not only did he help me to get it running great, but I also have a better idea how the carb works.

I will be going out of my way to make future purchases from FBO systems. Their prices are very competitive, and you cannot beat the customer service. All of us know that there is no such thing as a "bolt on" and it pays to buy from people who know what they are doing and are willing to get you through it. And, Don is a Mopar guy- enough said!!


Don Gould is one of the most intelligent, friendly, knowledgeable people that I have ever had the pleasure of working with. Don had answers to every question I asked, and even more importantly, all of the questions I didn’t ask! Don is fair, good with customers, and very, very good at what he does.

 Don worked on my 1965 Barracuda 340 for a few weeks despite headliner stuffing falling on him, broken seats, electrical problems (which he fixed), and an overabundance of advance. The car I received back from him is one of the most finely tuned instruments I’ve ever driven. It starts right up, it barks when I rev it, and man, does it sound nice. If you’re thinking about sending your car or parts to someone, don’t hesitate—run to this man. He’ll treat you right and you won’t regret it.

Thank you Don.

Morgan Engel

All is well, Corvette is purring like a kitten -or should I say TIGER!

That last $150.00 I spent was the icing on the $15,000.00
4 shops, 2 machinists and 300 opinions (all Wrong!) and you solved it in a "Heartbeat ",  too bad your stuck on those Mopars we could use you over here in Chevy Heaven.

Thanks again for all your help.



Thanks a bunch for your time, the Mighty Demon works great! I didn't even have to do much tuning, just lowered the float levels slighly and adjusted the mixture. I've never had a carb swap go that smoothly! The motor is idling in gear at 800 rpms with 12-13" of vacuum. No flat spots, no backfires or hesitations, it just works beutifully. I'm suprised at how much low-end this motor has, too. The 3.55's don't seem to be a problem for it. Just wanted to let you know you have another happy customer!!


Just wanted to let you know the re-curved dist is in and had some time to play with the car.  Better idle, better throttle response, better sound.  Very nice.  One negative:  It has an even greater traction problem now.  In a positive light though, I can now rationalize some Goodyear Blue Streak road race tires or some Hoosiers to my wife.  Safety issue now, right?  Ha ha.
Again, thanks.

No guesswork, you get it back and it is right. The only negative from this is I now have an even worse traction problem.


Don, you the man. My cousin down in Calgary was playing around for about a month with his 360 and I must have spent 4 hours on the phone giving him some pointers to get it into the ballpark. He constatly was complaining about no power and I suggested he send it to you for rebuild. It came back and he phoned me up and could hardly contain himself he was so happy. Just dropped by his place today on the way home from my sisters and he did an improptu smoke show in his back alley that he couldn't even get a bark out of before the rebuild.


   Just wanted to drop you a line and say, that everything you told me to do worked out great. All I did was lean the idle circuit to where you told me to. I also bumped up the idle a bit with the idle screw. Were still a little on the heavy side, but the car became Deadly consistant, and when the D.A. dropped, the car picked up.( Was using a freinds weather gauge).
       Again, thank you very much for taking the time, on the phone, to help me out. Needless to say, I dont think I'll be needing those green sleeves. I will however be contacting you when I'm done this season to send you this carb so you can go through it.
                  Thanks again,

 Just wanted to let you know, I went with your recomendations on the jetting. And, all I can say is, your the man! Car was dead on all day, plugs have a tan flesh color all the way down to where the porcilan meets the metal.
Thanks a bunch,

Whereditgo Racing
...................a phone call..................
I screwed up.......
Oh Oh what happened?
I forgot to turn on the cooling fans on Sunday in the first round, it ran 9.32 at 138 MPH and we won but the temp got to 280*.

Yikes!.....and what happened?

Nothing, the Cometic Gaskets held perfect, no problems at all the car ran normal all day,  faster and quicker.  The extra compression we got with the .027 gasket seems to have cut about .02 off the time slip.
That's 16 passes now on the Cometics no problems, the most we got out of a set Felpro's was about 10 passes.

That's great John, are you a believer now?

You bet I am, I called the engine builder and at first he didn't believe me, he's sold, and he'll be in touch with you soon.
If those hadn't of been Cometics it probably would have filled with water and grenaded the motor , best money I ever spent.

Thanks John I appreciate the call and the good news.

Hello, this is ______ from ______Machine Shop, I need to order some Cometic head gaskets are you the right Guy to talk to.......
LOL...yes I am.......

I ran across your tech article on tuning air bleeds on the 750 demon.
I have had my demon carb for two years and for two years it has been
running rich, sooting up the plugs, belching black smoke.
So yesterday I opened the air bleeds to .070 diameter as instructed in
your tech article and that made all the difference.
That carburetor is as good as gold now.
Thanks for sharing your information.

Everett  Wa.          

 Last night I adjusted the 4 corner idle and now it idles real smooth. I also gained another 1" vacuum at the same idle rpm. That is now a total of 2 1/2" vacuum at the same idle rpm as both of my eddies and the original AVS carb. These numbers are in neutral and I will be plumbing a vacuum line into the car to see what the in gear and cruising vacuum numbers are. The throttle response is even better than before, just like you said it would be
Awesome carb! Thanks

Need some help or advice, I'm here
Hours are 7am -4pm Monday-Thursday, Friday we close at 2pm. 


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