power valve question

-

11.2

Well-Known Member
Joined
May 31, 2007
Messages
354
Reaction score
10
how do you tell if you have the right one? i have 5'' of vacuum and a 3.5 pv and i'm thinkin i should go to a 2.5. i have some issues that i think is accelerator pump and i want to make sure i don't have other issues.
 
If you have an auto trans and are pulling 5" in gear, a 2.5 would be correct for your application.

Is your accel pump shooting fuel as soon as the throttle is touched? Do you have a big single plane intake? If you do, you may have to add bigger squirters.
 
i have a dual plane and yes squirter is adding fuel as soon as throttle is touched. i was at the track this weekend and went from a 670 avenger to a 750 demon dbl pump. i'm not sure if i'm going to stick with the demon due to the fact i have to many issues with it. but of course i ran a little quicker so it got my interest. it was terrible when i first put it on but i went up in squirters front and back and now it's good if i'm on my stall but if i try mashing the throttle under 2,000rpm it still bogs something fierce. it also hesitates down the highway if i'm cruising at 3,000rpm and mash it, this is where i wanted to be sure i wasn't confuseing the accelerator pump with a pv problem.
 
Sounds like the Demon is running lean on the secondaries. What jets front and rear are you running? What displacement engine is this on? How do your plugs look?
 
I had the same issue with my 750 double pump Holley. I changed the accelerator pump to a 50cc, and it took care of the issue.
 
i started with 76 in front and 80 in rear [stock] i went down to 73 on the front due to the fact the front plugs were showing rich. they look very close now but i haven't tried a wide open burn since. squirters went from 31 front and back to 37 front and back. i only changes one squirter at a time between runs.
this is on a eddy head 340.
 
oh yeah another symptom.
at the end of my run when i was slowing down to get on the return lane it would stall.
 
-
Back
Top