90 4g64 6 bolt in 90 4g63 6 bolt

[mightymousestd]

trying to find a crank for my 6 bolt 4g63 and noticing that the 85-92 model 4g64 has a 6 bolt crank so I can keep my flywheel. Based on my research, both cranks use the same main bearings so I should be able to just get stronger than OE main bearings for the 4g63 or 4g64 (whichever is cheaper) and use them. My question is will the stock sized pistons from the 4g64 work with the 4g63 block without clearance issues, or would it just be better to get 100mm bore pistons for the 4g63 block?

 

[HIGHPSI4]

The 4G64 pistons are bigger than he 4g63. You will have to run 4G64 pistons or stroker pistons.

 

[SpeedAddict62]

4G64 uses a 86.5 mm bore, which is equivalent to a .060 overbore on a 4G63 block. So no, you shouldn't use the 4G64 pistons. You could use stock 4G63 pistons, but you would have to get a 144 mm rod. Better to just go with stroker pistons.