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Discussion Starter #1
So I rebuilt the engine in my 74 Nova and made it into a 383 stroker. I put a Holley Demon carb onto it. It drives fine when I start slow, but when I go from a dead stop and put the pedal to the floor, the engine completely stops and will die if I don’t take pressure off the pedal. Does anybody know what this is and if so, what I can do about it?
 

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when i did my 383 i had to adjust the acel pump to run richer in my carb and re jet it.
it fixed most of it what fixed the rest of the same issue i had as you
im running a locked dis at 32* and vacuum advance hooked up thats pulling about another 15*

spend the money on a wideband afr guage kit itl help with your head ach there about $200-$250
 

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What cfm is the carb? Vacuum or mechanical secondaries? What kind of fuel pump & what is the pressure? As some else mentioned timing initial & is it with or without a vacuum advance? What kind of ignition are you using? What octane are you using? Compression ratio? Street or track car? All can give you that problem. Give me some of this info & I can try to narrow it down
 

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Discussion Starter #6
I’m gonna try to answer as much as I can with this one post but beware, I do not know a whole lot about this stuff, for instance what is cfm? I know my timing is around 25, I’m running a vacuum advance with a regular fuel pump, but idk the pressure. Idk what kind of ignition I have or what the compression ratio is but I do know that it’s a street car running premium gas (around 93 octane I think)
 

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I built my buddies hydraulic roller 383 and I have his at 18* initial and 18* mechanical timing for total of 36. My solid roller 383 I have at 26* initial and 10* mechanical.

If you don't have enough timing it will be lazy or usually backfire thru the carburetor if too retarded. Check pumpshot on carburetor also.
 

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Mike - 74 Nova Baltimore, MD
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I agree that it would be helpful to have additional details about your build to help diagnois the issue you are having (initial mech timing w/o VA, initial mech timing with VA, total mech timing w/o VA, compression ration, etc).

More often than not.... a bad engine bog during quick acceleration from a dead start is most likely caused by a lack of a fuel shot entering the carb when a large amount of air is introduced.
The first thing to check is that your accelerator pump arms are adjusted correctly. You also want to check that the fuel transfer slots that are under the primary throttle blades are not too exposed (you would need to remove the carb from the intake manifold to check this). If bog still persists, I would then suggests increasing the size of the primary (and possibly the secondary) accelerator squirters. You may also have to play with different accelerator pump cams to fine tune the amount of fuel shot into the carb.

There is an art to tuning a carburetor for each type of engine build and it does take some time and testing.
 

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Discussion Starter #10
If the 25* is total, you found your answer. <img src="http://www.stevesnovasite.com/images/yes.gif" border="0" alt="" title="Yes" class="inlineimg" />
Still would like to know carb,cam,converter, gearing...
I know the carb is a Holley demon, but I’m not sure of the cam converter or gearing. Sorry for the lack of knowledge guys but this build happened about a year and a half ago, it was my first introduction to anything engine related, and we can’t find receipts for anything I have
 

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