carb question???

[84supreme]

this might be a dumb question, but i have an 84 cutlass supreme with a 307 running the factory rochester carb. would it be possible for me to run my holley 650 cfm? would it bolt right up or would i need an adapter plate or something? thanks

 

[Pontiac455]

It depends if the holly carb is a square bore or spread bore. Yer intake is spread bore so if the carb is square bore u'll need a adapt. plate

 

[84supreme]

o ok thats what i thought, i cant remember but im pretty sure my holleys square bore, so where can i get an adapter plate?

 

[JBreu]

You can get an adapter plate from Advanced Auto, Summit and Jegs.....They have the reversable adaptor plates to go from spreadbore to squarebore or viseversa 🙂

 

[84supreme]

ok i got an adaptor plate, will my air cleaner and everything fit and the hood shut with that adaptor in there? and is there anything i need to change on the car since im going from the rochester to the holley?

 

[FE3X CLONE]

You'll need to change the distributor to a non-CCC HEI.

And obviously the fuel line from the pump will be different.

Also, assuming you have a TH-2004R you'll need the correct throttle cable bracket for the Holley and then make sure to adjust the TV cable properly otherwise you'll burn the trans up.

 

[houndin101]

ok i got an adaptor plate, will my air cleaner and everything fit and the hood shut with that adaptor in there? and is there anything i need to change on the car since im going from the rochester to the holley?

on mine a went from a Q-jet to holley i needed a adapter plate it came with both kinds of adapters...my hood fit barely it formed in the insulation so i took it off now it fits good i got maybe a half inch between hood and air cleaner

 

[houndin101]

this is the adapter

 

[joe_padavano]

this is the adapter

Wow! That photo is the perfect example of why you want to get the correct intake. The sideways holes that neck down to the small primary barrels can't be doing a lot for flow. Why spend the money on a Holley just to run this "restrictor plate"?

 

[houndin101]

this is the adapter

Wow! That photo is the perfect example of why you want to get the correct intake. The sideways holes that neck down to the small primary barrels can't be doing a lot for flow. Why spend the money on a Holley just to run this "restrictor plate"?

doesnt hurt flow at all and if you change from a qjet you have to get an adapter