head up grade
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head up grade I have a 99 Z71 with a 5.3. I have a blowed head gasket. Instead of doing a valve job on my heads a buddy of mine said he had a set of either 241 or 243 heads that had already be redone with a valve job. Any suggesting
Last edited by chevy99z71; Dec 29, 2009 at 10:39 AM.
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From: BFE
You must mean 241 or 243 heads. 243s will work well if milled a bit, you'll need to use LS1/LS6 gasket. 241s have too big of a chamber and will negate any gain in flow (which is minimal) over your 5.3L heads.
799 (similar to 243s) will work well too.
799 (similar to 243s) will work well too.
Thread Starter
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Would you use the ls intake or keep the stock intake. I am going to use the 241 heads for right now because i can pick them up cheap, and i know they are good so i dont have to wait on mine to get back,so i can get my truck back on the road.
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From: BFE
Suit yourself, you'll loose about 4>5cc in chamber size, thus reducing compression and power output.
5.3L are 61.5cc and 241s are 67cc
You'll need to use LS1/LS6 head gasket, not 5.3L gasket which has a smaller bore.
5.3L are 61.5cc and 241s are 67cc
You'll need to use LS1/LS6 head gasket, not 5.3L gasket which has a smaller bore.
It just feels better when the idea is confirmed by an expert.
