Holley carb issues

[bigdan]

glad that i helped you out! 🙂
like many here i prefer a quadrajet over a holley ....

but if your holley is in good condition ( no loose in the shafts ) run it .
most intakes have the square holley flange but some leave you the choice .
if so get the quadrajet flange (for future)

your flowtech headers will do the job if in good condition ...what size are your primary tubes...if 1 1/2" they are mostly for torque & economy usage go for at least 1 5/8" or 1 3/4" tubes if you switch

Dan

 

[Lue]

glad that i helped you out! 🙂
like many here i prefer a quadrajet over a holley ....

but if your holley is in good condition ( no loose in the shafts ) run it .
most intakes have the square holley flange but some leave you the choice .
if so get the quadrajet flange (for future)

your flowtech headers will do the job if in good condition ...what size are your primary tubes...if 1 1/2" they are mostly for torque & economy usage go for at least 1 5/8" or 1 3/4" tubes if you switch

Dan

Well, the Holley that i have now is farely new, and in great shape. But because i want to gain the HP, I'm going with a larger cfm carb like the article call for.

 

[megaladon6]

i wouldn't worry about the carb size too much. the magazines always use 750's even though they know it's overkill. the formula is;
cfm=CIDxRPM/3456 therefore 350x6500/3456=658cfm. and this assumes 100% Volumetric Efficiency which you won't have. unless you are building for the drag strip and need only top end power 650-670cfm will be fine. and that's what holley's are best at.
for all around driveability with slightly better MPG and slightly less power you go with a q-jet. they are a 750cfm carb but due to their design they only pull as much air as you need. (see the sticky in "how-to's")
i'd do the intake (watch your hood clearance with an air gap!!!) and you already have headers. you also want a full dual exhaust, preferably with an X-pipe.

 

[Lue]

i wouldn't worry about the carb size too much. the magazines always use 750's even though they know it's overkill. the formula is;
cfm=CIDxRPM/3456 therefore 350x6500/3456=658cfm. and this assumes 100% Volumetric Efficiency which you won't have. unless you are building for the drag strip and need only top end power 650-670cfm will be fine. and that's what holley's are best at.
for all around driveability with slightly better MPG and slightly less power you go with a q-jet. they are a 750cfm carb but due to their design they only pull as much air as you need. (see the sticky in "how-to's")
i'd do the intake (watch your hood clearance with an air gap!!!) and you already have headers. you also want a full dual exhaust, preferably with an X-pipe.

Ok, good to know. I already have the true duel exhaust with an X-pipe. So one thing less to worry about.

Has anyone heard of Sean Murphy Inductions ( http://smicarburetor.com/ ) ? Someone reffered me to them, and said that they put out good quadrajets.

 

[85 Cutlass Brougham]

You also do not want a double pumper carb on a street car application--unless you like using too much gas. Plus, even the Vac Secondary 3310 is too rich as it comes since the idle air bleeds are tuned for a L78 396 ( it's OEM application) and not a 350.