LQ9 6.0 head milling question
LQ9 6.0 head milling question I'd like to know how much I can mill the #243 SDPC CNC LS6 heads on the LQ9 that's in my '99 Z28 without P/V problems.. First of all the heads have never been milled.. They are 70cc LS6 heads.. Now I know the stock 6.0L heads are 71.06cc. I could probably just bolt them on and use the stock length 7.4" pushrods as is if I wanted.. However, I figure I can pick up some power by milling them.. I'm assumming the deck height is the same from the LS1 to the LQ9. So would I be safe in having the heads milled .030" like the LS1 and running the 7.35" pushrods? What would the compression be? I'm also assumming slightly more than a similar LS1 due to the slightly larger bore. I'm running the TSP 228R cam which is 228 228 .588/.588 on a 111 +4 advance.. I don't want any P/V clearance issues..
Thanks
Michael Eller
Thanks
Michael Eller
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Re: LQ9 6.0 head milling question Mikey,
you're going to run into P/V issues with that much lift. anything more, and i'd definately break out to play-doh and clay that motor. you'll have the heads off anyway, and it'd be a shame to have messed up those 4" bore flat tops, as they're pretty hard to come by.
ok so,
yes, the deck height is the same, 9.420". if you mill the heads .030 and are using LS1 valves and not LS6 valves, you'll be fine on p-rods, w/ that 228 cam. i dont know about p/v. my cam is 232 on the intake side and .580's lift and i had roughly 140-160 thousandths of clearance. (no gasket, & valve reliefs). long story short, just be sure and clay it first.
you're going to run into P/V issues with that much lift. anything more, and i'd definately break out to play-doh and clay that motor. you'll have the heads off anyway, and it'd be a shame to have messed up those 4" bore flat tops, as they're pretty hard to come by.
ok so,
yes, the deck height is the same, 9.420". if you mill the heads .030 and are using LS1 valves and not LS6 valves, you'll be fine on p-rods, w/ that 228 cam. i dont know about p/v. my cam is 232 on the intake side and .580's lift and i had roughly 140-160 thousandths of clearance. (no gasket, & valve reliefs). long story short, just be sure and clay it first.
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Re: LQ9 6.0 head milling question N/P there big guy, dyno that monster.. im going to try to get mine done saturday 
i wanna know what numbers a more factory 6.0 shortblock would make.
i wanna know what numbers a more factory 6.0 shortblock would make.
