Mighty Demon 750 rich jetting???
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Joined: Apr 2015
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Mighty Demon 750 rich jetting???
First off This is a ford XD , I just bought a 1970 torino with a 1971 460 stock with a rv cam,
It has a Mighty Demon 750 on it and the car idles great, starts great, but when u rev it up it smells of fuel burning your eyes. when u drive it sounds super rich cruising or stepping on it. I bumped up the timing and it helped but this carb is clearly too rich. I set the floats as well. IT acts like I have a race carb on a stock motor which looks to be the case when u click that link. but I don't want to buy another carb until next year.
SO my question is can this carb even be jetted down? If so what jets do I try, stock primary jets are 71's and secondary's are 75's.
https://www.summitracing.com/parts/dem-5402020gc
It has a Mighty Demon 750 on it and the car idles great, starts great, but when u rev it up it smells of fuel burning your eyes. when u drive it sounds super rich cruising or stepping on it. I bumped up the timing and it helped but this carb is clearly too rich. I set the floats as well. IT acts like I have a race carb on a stock motor which looks to be the case when u click that link. but I don't want to buy another carb until next year.
SO my question is can this carb even be jetted down? If so what jets do I try, stock primary jets are 71's and secondary's are 75's.
https://www.summitracing.com/parts/dem-5402020gc
Supreme Member
Joined: Oct 2004
Posts: 4,528
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From: Henrietta NY
Car: 1984 Trans Am L69
Engine: Sniper EFI Powered 355
Transmission: WC T5 w/ Steel Support Plate
Axle/Gears: 3.42 10 Bolt Posi
Re: Mighty Demon 750 rich jetting???
Try calling demon and asking their tech line. If not someone on a ford forum might be able to help
Senior Member
Joined: Feb 2008
Posts: 706
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From: Central PA
Car: 1990 IROC
Engine: Rebuilt L98 with H/C/I/Carb
Transmission: TH350 with ATI Treemaster
Axle/Gears: 7.5 with 4.10's
Re: Mighty Demon 750 rich jetting???
I have that carb on a 500HP 355 and it ran a little rich out of the box, but wasn't horrible. I would make sure the timing curve is good (you are running vacuum advance...correct?). After that, then you can look at the carb. The carb uses Holley components (jets, PVs, many of the gaskets). Sofa's Tuning sticky in this forum is an excellent place to start!