Hi all, first posting and will look pretty lame to you experienced engine builders!! I've just pulled the heads off my Chevy 350 and the casting on the heads relates definately to a '76 305. As far as I am aware the block is a 350. I've checked the casting number on the block (3970014) and it seems to be a 1970-73 two bolt mains 350. Were the heads interchangeable? ....is it likely that 305 heads would have been dropped onto a 350 block? Confused Thanks guys ....
305 heads on a 350 isn't all that uncommon anymore. Real "pro" engine builders will quickly tell you that a 305 can only make a maximum of about maybe 15 horsepower, whereas a 350 with the same equipment routinely produces about 600 ponies for two thousand dollars less than a 305 costs to build...or whatever bullshit they wanna spew forth today! Bottom line, you got a small block Chevy with small block Chevy heads on it. Most 305s have small chambers, so someone may have swapped the heads along the line hoping to bump up the compression some. Another possibility is that the heads were swapped at some point to make the engine compatible with today's unleaded gasoline. All one needs is a calendar to realize that it's not the 60s anymore...but while we wait for some to catch up to the times, you may wanna do an intro before the trolls rise up to shake their fists at ya!!!
I have a set of 305 heads on my 350,casting #601,they have 54 cc cumbustion chambers,they been worked though,fully ported and 1.94 valves.
Anybody who loves the world's best V8 should have this site bookmarked. http://www.mortec.com/castnum.htm Looks like you do indeed have a 350.
The Jalopy Journal
