Visit The Dirt Forum for More Information

Author Topic:   engine
Dirt Roller

Total posts: 22
posted June 08, 2002 09:16 PM
My ? is: if a 350 chevy bored .30 over is a 355, then what would a .40, .50,.60, over be?and what are the advantages and disadvantages to being bored this big. I would think the bigger you bore it, the hotter the engine would get.

Thanks, JJ

p.s. what are the horsepower ranges of the 40,50 and 60 over?

Dirt Forum Racer

Total posts: 87
posted June 11, 2002 12:00 AM
A .040 over is a 358
A .060 over is a 362
I would guess that if you found pistons that are .050 over (personally I never seen any or built a .050) you would have about 360 ci.

I've never sat and compared computer numbers for the .040 and .060 over versus .030 and std. bore engines, but what happens when you go with an oversize piston is that you have more piston surface area against the head so your cylinder pressure will usually increase slightly for a minimal HP gain. Depending on what type of pistons you are using, you may not notice any gain at all. That's how I've always viewed it. If you are boring and rebuilding a tired std. bore engine though, just the fresh bore, piston, and rings will make a big difference.

Back to the Archives