Im just wondering if anyone is using a 4175 carb. The one I have is part # 0-80555C its a 650 Q-jet replacement. Im using vortec heads Comp 268 cam (.480 lift) Would it be a good perforamance carb for this?

 

It's a decent carb. The 4165 is a double pumper, I ran one of those for awhile summer '07, the car wasn't any quicker than with the stock CC q-jet (lots of data to prove that), and mileage was slightly worse. The 4175 has an electric choke, a definite advantage over the 4165.

I'd rather run a standard 4150 double pumper.

 

I would also rather run a 4150 double pumper, but sadly I dont have one. So are you saying that the 4175 is also a double pumper but it has an electric choke whereas the 4165 is the same but with manual choke? Do you think the 650 4175 is to small for street/strip with my heads/cam?

Im also having trouble finding an intake to go with, I want a performer RPM because I feel the standard performer isnt enough but the RPM only comes in square bore so I would need an adapter plate but then I worry about hood clearance issues.

 

After looking into this I want to use this carb as long as I can find an intake to go with it. I dont really want to use an adapter plate and I cant find the intake I need.

I need to find a SPREAD BORE VORTEC intake that is comparable to the performer RPM. My cam is comp cams 268XE which has .477/.480 lift. Any suggestions for intake.

 

4175 has vacuum secondaries, the 4165 has mechanical secondaries.

 

Correct.

To the best of my knowledge, there is no Performer RPM Vortec spreadbore intake out there (and I've looked). The only choice is squarebore carb or squarebore to spreadbore adapter.

 

Anyone think the RPM manifold and adapter plate w/carb will fit under the hood of an 85 T/A???

 

No. Just the RPM and drop base air cleaner alone is an extremely tight fit.