about to order lowcompression pistons and im depating if i want to bore out my block to 81.5 or leave it stock bore. are the gains worth it? i also keep thinking that by boring out the block it will weakin my sleeves alittle bit. im looking for 400 on bump gas on my stock head b18c1

 

more than likely your cylinders will be out of round so you'll have to bore it out.

 

If you plan to make power down the road I would sleeve it. Deff would get it bored to 81.5 though..