what the biggest holly you guys think would work best on a 12a?

 

Do a search with the term holley/holly.

Been covered 1000 times.

 

Can't forget Edelbrock or Sterling, either.

 

Bigger is not always better, carbs or porting.

 

ditto! 500 cfm is max in my eyes!

 

naw i have seen 650-700and even 800 CFMs on na motor.

 

^ Not on a stock port rotary 12A engine.

 

+1 anything over 500 is a waste of time on a stock ported motor. Is your motor ported or stock?

 

A holly 600 runs great on a stockport 12a.

 

it is stock port motor but i ported the stock intake manny like crazy

 

racing beat's holley setup for the stock port is a 465cfm. i was running this setup on an '83 12a with excellent results. the streetported 13b i'm currently running was sitting waiting on a rebuild at the time and it had rb's 600cfm holley. i decided one day to see how much difference there would be between the two, so i switched them. the 600 was way too much for the stock 12a compaired to what the 465 was. i'm sure the 600 could have been made to run better with some smaller jets.

 

well thanks for all the help guys one more qustion car i de jet a holly 750 down far enough to work fo rme or do i have to buy a smaller carb? i got this 750 for 50bucks and it works so i was going to try to make it work for me

 

You should see if someone wants to trade for a smaller one. You can probably make the 750 run, but it won't work very well.

 

Nope, the venturi's are too big to get proper flow for the lil 12a. Put it this way, it would be about right for my 1/2 bridge supercharged 13b

 

750 is to big smaller jets are less fule but not less air... yes you can get it to run in a pinch but its going to run like crap 500cfm is max for a stock port 12a

"edit"
besides if you have never done a holley for a rotory and if that carb is not for a rotary you are going to be going down a very very long road.. hope you know holley carbs VERY VERY well

 

ok

 

2983479823727983759872345 cfm

98179812734982734972398723479723987448972387239487 cfm if ported

good luck!