mikep2002

iTrader: (10)

Have a friend looking at buying 402 shortblock the question is will his prc 243 heads fit until he can afford some 225 heads. And if so what size gasket should be used because of the larger cylinder size.

I understand there is also a question of wether or not the piston comes slightly out of the cylinder havent gotten to check that far, to this point just considering the basic pinciple. Of putting LS6 heads on a 402 to get bye?

Thanks for any insight.

firefighting1101

iTrader: (48)

Yeh the will go right on. wont make the greatest power, but they will work

mikep2002

iTrader: (10)

Another question head gasket what size LS6 gaskets or 6.0 liter gaskets?

Sales4@Texas-Speed

iTrader: (4)

You will want to go with the 6.0 litre gaskets since you have a larger bore.

mikep2002

iTrader: (10)

Thanks John appreciate the answer... Will forward the info..

Clevite Kid

The piston protrusion MUST be less than the compressed gasket thickness, plus a margin of safety, or there will be trouble.

Protrusion on a stock LS2 short block is about 0.007". Most builders will not go thinner than 0.036" Cometic gaskets, for a thin 0.029" quench distance. Others have used 0.030" Cometic gaskets and have NOT busted a piston or a head, even with only 0.023" of quench distance.

One reason: the aluminum block expands with temperature a three times the rate of expansion of the steel connecting rods. That is a good thing .