Quick question. I need to rebuild my 416 heads for a 305 motor that sees 2500-4500 rpm. I have a set of fresh 350 vortecs 1.92/1.5" valves with intake that I may use instead. Which would flow better? The 416's have same size valves, but otherwise stock (I think). My concern is the compression drop with using 64cc Vortecs on a 305. The 416's are 58cc and the cam is mild .400 lift. thanks for any input.

 

The Vortecs will flow a little better, and will probably make up the loss from the lower compression.

I assume 1.9" intake valves were installed in the 416's at some time.

 

350 heads on a 305 is a big mistake man.....

 

Depends upon which 350 heads. In this case, it is not a "big mistake".

 

Not the Vortecs, especially if you mill the heads some and use the Felpro rubber embossed steel shim headgasket (4.100 x .016" compressed). Not even milling the heads, you will still be around 9:1 with the Felpro head gaskets.