Would anybody happen to know what the stock cfm is on a 1987 5.0L (305)??? It's actually on a pickup instead of an F-Body, but I figured what they hell...I'm half-tempted to buy a 670 cfm TBI system, but i'm not sure as to how much of a jump that would be from stock...any helpful information would be greatly appreciated.

 

I've heard 450cfm.

 

No wonder you couldnt find it. I searched all over the TBI board and couldnt find anything on the stock TB CFM. I thought it was something like 490 cfm but dont hold me to that.

 

Unless you're burning your own chips I highly suggest you skip right on over the 670 throttle body. The big throtte bores really change how much pump shot your engine will need, as well as the way it idles and responds to the IAC. In all reality you don't need the big throttle body untill you start making over 275 hp. Fast355 put up some very good numbers with a stock 305 TB.