243s compared to 317s

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Feb 23, 2009 | 01:46 PM

Do Work Son!

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Staging Lane

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From: Moody AFB Valdosta GA

243s compared to 317s

I am aware of the obvious cc difference, but which one creats better bolt on performance? I have both in my garage but don't know what will work better w my cam and 150 shot

Feb 23, 2009 | 02:14 PM

sroach20

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get the 317s milled and sell the 243 heads. you can get more money for the 243 heads and get the same results with the 317s if you mill them.

Feb 23, 2009 | 06:57 PM

Hard Core Z28

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317 are better for boost cars that want to lower you compression. The 243 are best for you needs. The 317 will be a dog.

Feb 23, 2009 | 06:59 PM

shtnfrds

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mill the 317's. sell the 243's. sleeper racing, anyone that knows about 243's can see that casting number on your heads. get the 317's and more times than not you'll get them thinking you got nothing special.

Feb 23, 2009 | 07:06 PM

regency

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thats way too much milling to reach the cc of a 243 from a 317 head. you would need to mill like .030 then check cc and mill more accordingly. you get to a point when milling that it starts to take less out "cc" wise.

Feb 24, 2009 | 12:26 AM

Do Work Son!

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Staging Lane

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From: Moody AFB Valdosta GA

Milling was an option, but i had no idea how far to mill, and if i would still even be at a ratio close to the 243s. anyone wanna buy some 317's?

Mar 7, 2009 | 08:19 AM

A_VAS

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what's the published CC of the 243 heads?
I just CC'd a set of 317 heads here with spark plug and came out 70.6

I'm looking for the reduction per milling but if I can't find it will calculate it best I can.