706 heads with boost

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Sep 6, 2013 | 09:55 AM

Turboswede

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706 heads with boost

I found out that my lm7 got 706 heads, from what I have read they are ****. Would it be worth to change cam, push rods and valve springs and boost with this heads in a "junkyard build" or try to find some other heads?

Sep 6, 2013 | 11:37 AM

a-low

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Im using those heads on my 5,3 build. Had them rebuilt and had a 3 angle valve job a
nd tooley springs installed. should matter too much on a boosted
application.

Sep 6, 2013 | 11:52 AM

87silverbullet

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You'll be fine for a JY build. leave them on there.

Sep 6, 2013 | 11:57 AM

Ferocity02

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The issue with these heads is that are prone to cracking and leaking coolant, it's a Castech casting flaw. This is not an issue on all 706 heads, just some.

http://ww2.justanswer.com/uploads/Bl...t_loss_5.3.pdf