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*Billla* · 02-23-2008, 05:25 AM

I'm not sure I fully understand the question - are you overhauling the engine, or you're looking to raise the CR by bolting on new heads? If you're looking for hypereutectic pistons, there are a lot of choices that will work with any head selection.

Swapping from a 76 cc to 64cc head will raise the CR approximately 1.1 points.

A 1 point increase in CR is worth maybe 3% power increase on an engine that's making around 1 HP/CID...so unless you're stuck on increasing the CR there are other ways to make more power - and for less money.

I have no idea what the comment is regarding Vortec heads and cracking; I've never heard of this happening. They certainly don't "crack real easy".

More information on your usage and budget would help. Usage drives the cam selection, cam drives the head and the rest of the engine is built around those two pieces.

02-23-2008, 05:25 AM	#7
Billla Account Suspended Join Date: Sep 2005 Location: Monroe, WA Posts: 3,814	Re: Performance help I'm not sure I fully understand the question - are you overhauling the engine, or you're looking to raise the CR by bolting on new heads? If you're looking for hypereutectic pistons, there are a lot of choices that will work with any head selection. Swapping from a 76 cc to 64cc head will raise the CR approximately 1.1 points. A 1 point increase in CR is worth maybe 3% power increase on an engine that's making around 1 HP/CID...so unless you're stuck on increasing the CR there are other ways to make more power - and for less money. I have no idea what the comment is regarding Vortec heads and cracking; I've never heard of this happening. They certainly don't "crack real easy". More information on your usage and budget would help. Usage drives the cam selection, cam drives the head and the rest of the engine is built around those two pieces.