Head Gaskets?

[ChevyGearHeads]

I have a Target Master 350 LM1
and I was going to put the Summit SUM-152123 heads on it.

The Block is suggesting a 4.100" bore gasket and the heads are suggesting
a 4.125" bore gasket.

I'm not sure what gasket to get

Thanks,
Paul

[AussieinNC]

Originally Posted by ChevyGearHeads

I have a Target Master 350 LM1
and I was going to put the Summit SUM-152123 heads on it.

The Block is suggesting a 4.100" bore gasket and the heads are suggesting
a 4.125" bore gasket.

I'm not sure what gasket to get

Thanks,
Paul

Use what the heads require...but read below...is the engine a roller cam or flat cam engine?

The LM1 is better known as the target master 350 produced in mexico for gm from 1980 to 1994 it was GM,s economy 350 4 bolt main replacement motor rated at 185 HP 300 ft lbs torque and came complete less carb and dist.
After 90 it came drilled for roller cams it is one of GM poorest produced replacement motors ever the cam only lasted 30.000 miles and where full of casting flanges not trimmed on the internals the would break of and cause engine failures .
When new there was the need to be disassembled and cleaned up and cam replaced to make a reliable engine.