jet size question?

[sean68charger]

the main primary jests in my holley 750 vac sec are the standard (factory) 72`s. i have a feeling that they are too small for my 440hp. what jets are you all running in yours or any recomendations?

[Ghoste]

I have 74's in my 383 but my first question would be; why do you think yours are too small?

[Chryco Psycho]

WHat is the color of the plugs after a 5 mile hwy cruise ?

[sean68charger]

she runs fine and pulls well on the idle circuits up to about 2750 rpm then bogs/misses but pulls realy well when the secondaries open. this only happens on a gentle to moderate acceleration. if you floor it as if you were running the quarter mile she pulls well and strong all the way thro
the problem has been getting progressively worse as i add things like a better flowing intake, exhahust, and air filter etc.
i wired closed and disconnected the secondaries, and the problem was still there all the time from 2750rpm onwards no matter how gentle or hard on the throttle.
at idle you pull the plugs and they seem perfect, but its hard to tell with the problem in this rev range, so i thought the jets might be a bit small for a 440

[jg68]

Try putting in some 74s, see if it helps

[firefighter3931]

Stuff like headers and free flowing aircleaners will change the jetting requirements.....it needs more fuel on the primary circuit. 



Ron