Rebuilding a stock bottom end LQ4 with a set of 862 ported and polished heads. Motor has 228R cam and will be not be turbo or boosted. Just good ole NA fuel injection.

What head gaskets should I use? LS9?

thanks in advance,

Dogman............

 

Gonna need more info on the heads chamber size? Were they milled? I'm thinking now either stock gm or cometic .040s dead in on what the head specs are

 

Its a stock block, 862 heads milled 010 for cleanup only. Lq4 pistons.

 

In that case I would look into decking the heads a bit and going with a thinner gasket. Reason being is that with the lq4 piston and the heads you'll be at 9.75-10:1 compression. Whacking .020 off the heads and running a .040 gasket will bring compression way up. I would just check ptv clearance though to be safe

 

862s are 5.3 heads and already have a 61cc chamber (317s from the 6.0 have 71cc) which will put his CR at around 10.7:1. No need to mill anymore off them

 

OP where are you getting the heads from?

 

I already have them. I bought a 5.3 shortblock that was totally rebuilt and the PO worked at a speed shop in Killeen, Tx and had installed bigger valves and ported and polished the 862's off the 5.3.

I bought a 6.0 and am gonna use the 862's on the 6.0 and probably build the 5.3 for my 2000 silverado work truck. Lol

 

Gm gaskets 12589227 work great...

 

My 862's are at a 61cc chamber, and with flat top pistons on my LQ9 it puts me around 11.5:1 compression with the stock GM gaskets. Get that compression up a bit and those heads do pretty good

 

Make sure the heads don't have the notch in them, or you will have to use a graphite gasket.

 

Can someone post photo of this notch?