vettenuts

iTrader: (4)

Does anyone know the bore diameter, compressed thickness and whether an LS3 gasket will go on an LS1 block?

rsz288

Did you get an answer? The later 6 & 6.2L GM head gaskets are the same items (ed: except on LS2). They support the 4" and 4.065" bores. Given the aftermarket (replacement parts, not performance parts) uses a single head gasket for LS1 through LS7 (which IMHO is not the right approach), a GM MLS 6/6.2 may work on a later style LS1 (but maybe not the early style with the composite gasket.) Best to check, as the the 6/6.2 gasket is 4.105-4.11" dia.

Compressed is supposed to be .051, but I have measured uncompressed at 0.048. So ?

NemeSS

iTrader: (127)

i have measured a 6.0 mls gasket at 4.044 and .055 compressed
and a 6.2 at 4.083 bore and .051 compressed
thats a big difference,
i would not use a 6.0 4.044 bore gasket on a 4.065 bore engine.

Shawn @ VA Speed

iTrader: (3)

the l76 6.0 and the 6.2 head gaskets are the same,but the ls2 6.0 is different.
i have used the ls2 gaskets on ls1's but not ls3 gasket.i cannot see a problem though as it should still seal up on the cylinder sleeve

NemeSS

iTrader: (127)

correct, i meant the 6.0 as in the lq4/lq9 engines have the 4.04 bore
the l76/l92/ly6/ls3 use the 4.08 bore gaskets

rsz288

Very good point! I should have double checked before I posted, but the 6/6.2 gasket is 4.105-4.11" dia. The LS1 @ 3.9" may lack adequate sleeve sealing area with one of these gaskets.

I have seen aftermarket "run of the mill" replacement gaskets @4.13", which may be marginal on an LS1.