? on CR

[Guest Lee Smith]

I have a 69 350 4bl

 

Chilton says 10-1 CR 295 hp. with a 4bl. It

needs a valve job.

I have later heads that the valves good in. No

idea what yr.

Will I lose the 10-1 CR? The later 350s have

8.5-1.

I like the thought of 295 hp. stock, low $$.

I am doing a 77 V8 swap.

 

Lee

 

PS I have 3 finished cars, stock. Pics on ZDriver

Rides 78-82-83 Lee Smith If interasted.

[Mike C]

You will lose the compression to some degree. The later heads will probably give about 9:1 with the early pistons. I would rebuild the heads on the '69 with new valves, exhaust seats, and guides. David Vizard, "How to build and modify small block chevy cylinder heads" Says the closed chamber heads are worth 20 more hp than the open chamber heads, all else being equal. Or just by a set of aftermarket heads with the 64cc chambers as they have learned a lot about combustion chambers in the last 30 years.

[Guest Anonymous]

There's a good compression ratio calculator at

http://www.gafba.com

if you want to figure out exactly what the CR would be.

[pparaska]

That's the most thorough CR calculator I've seen. With all the data they are asking for, they appeart to be calculating the volume around the piston top above the top ring and using it in the analysis. Very correct, very nice.

[Guest 400 ci 280z]

that is a nice cr calculator. it says i can get 9.3 cr with out having to mill my heads on my pont.