is a holley 750 vs carb to big for a modded 350?

 

I wouldn't think so... 750-800 cfm carburetors were quite normal during the late 70s on 350s.

It just depends on how you jet the carburetor and tune it for your motor.

If it's a BONE stock 350.. like one from say.. a pickup truck in the 80s, then I'd say yes, it's too much.

 

what mods have you don to this motor?. if it was stock then yeah i would say a tad bit big.

 

A 750cfm carb is just right for a 350.

 

I'd be more inclined to question the VS decision.

 

the 350 is from late 70s. holley contender intake,high lift cam, full rollers, i think she has been bored, headers, cataback with high flow cat, 3.42 gears, th350 tranny. i am just going though my list of what can cause my lack of power off the line and alot of people say carb might be to big. is it possible to be to small with the mods i have?

 

The carb is not too big or too small but may need tuning.

Accelererator pump shooters and cam, vac sec spring, etc.

Go to the holley site for tuning info.

The motor may/will want more initial timing at idle with a larger than stock cam.

Should be 12 to 16 deg at idle. You may have to recurve the distributor to get the right initial at idle, timing curve and total advance at high rpm. the OEM stock timing corve is not the best for a modified motor.

The torque converter stall speed may be too low for the cam duration. Or the cam is too big for the converter stall. Take your pic.
Does the motor have a "rough idle"?
Again, the carb is not "too big".

 

F-BIRD'88> thanks! and thanks alot for the timeing info i was going to ask about that. ya the car does have a rough idle.
and i have lightest spring in there already i will check into the other things.
ya i am also thinking it may be my stall as u pointed out.
when i am adjusting the timeing i read on hear u are suppost to discontect something first what is it? because every time i get a mechanic to do it they never disconect anything.
thanks for the help people
oh another thing i forgot to say is when i am on the highway and i punch it i get a nesty smell afterword, any ideas?
thanks again

 

You what to disconect the vacuum advance hose from the carb when setting the timing.
then when your done reconect it to Ported vacuum on the carb.

the ported vacuum source has little or no vacuum at idle when the throttle is closed. Then vacuum increases as you open the throttle.

As opposed to full manifold vacuum which will show vacuum at idle.