port/polish/milled 862 heads, Worth the $$$
Oct 21, 2007 | 01:48 PM
#21
I was looking at my buddies 07 sierra crew cab 5.3 and noticed the casting number on his heads was 243. I know for a fact he doesn't have the L33 HO 5.3 either. When did they start using LS6 castings as stock heads for the 5.3s?
Oct 21, 2007 | 01:56 PM
#22
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sauldgold
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