I have an 86 bird that has a 305 with the 4bbl q-jet. I'm not sure of the cfm. I am building a 355 with vortec heads and a mild cam. A guy at work has a Holley 750 dp that is only a couple of months old that he has offered to me for a great price. He said it was to much for is truck so he went back to a 650 I think. Would this be to big of a carb for my build or should I just use my Q-Jet as it works great on my 305, or should I look for something else? Thanks!

 

I'd use the holley.
With your vortec heads, you'll need a vortec intake. It's harder to find a vortec carb intake that has the q-jet bolt pattern, but the squarebore style one is more common. Running an adapter is hard with a firebird hoodline.
The holley should work very nice with your setup.

 

I'm using the performer with my vortec heads and the ccc-qjet, no adapter needed.

 

oh right, but there isn't a performer RPM q-jet for vortec right?
I guess Performer would work ok...

 

He's using a 'mild' cam anyway. Besides, I suspect that the differences between the vortec performer and vortec rpm performer are less than the differences between the two standard models. Vortec heads use a raised runner and you can see the diff in height between the standard performer intake and the one designed for the vortec heads. I'd like to, one day, see a comparison using the vortec models.

 

Thanks guys. I may try using my Q-jet and get the performer intake.