ok anyone have anyidea what the diffenerce is in the 862 and the 708 heads on the lm7's. been researching and can't find anything,. my 2000 has the 862's and my mothers avlanche has 708's and her truck is pretty f***ing fast.
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ok anyone have anyidea what the diffenerce is in the 862 and the 708 heads on the lm7's. been researching and can't find anything,. my 2000 has the 862's and my mothers avlanche has 708's and her truck is pretty f***ing fast.
706 and 862 are the same heads just different casting numbers. If I recall correctly one of them had coolant issues. Not positive on which one.
706 heads were sand cast and the port seams were non-existant. in the 862 heads, the casting cores don't match up correctly and you end up with the bottom of the ports offset about 1/16th of an inch. and they don't flow worth a crap.
thanks just curious, never had any coolant problems at 206 k. so if i did come accros some 706 is it even worth the time to change out, maybe freshen up some stuff. new head gasket? i would like to run this motor till she dies but at the same time ready to procharge a 6.0l. man everytime i think about that i get excited but my wallet doesnt//