Join Date: Jan 2002
Location: Calgary, Canada
Lonnie67, Depends on how heavy a piston you use, as heavy pistons tend to beat the walls around a lot. Do you HAVE TO bore it to 060? A 030 bore ( 4.155 ) is a safer bet, probably will make as much or more power due too less cylinder wall flexing ( can you say ring seal? ), you are only sacrificing 6 C.I. at 4.155. I personally do not like too see less than .205 wall thickness finished machined. This is almost impossible with a production block, unless you have a lot of blocks too test. I also run a production 400 block in my race car, I sonic checked 23 blocks until i found a suitable block. Actually ended up with a fairly nice thick block with a finished size of .230 average. Dont necesarily count out the block if there is a variance around the bore. Dont forget about engine crank rotation, as it places more load on the walls on the thrust side. Hope this helps. P.S. My stuff made 735 on the Dyno. All Motor.
2002 Jerry Bickle Cavalier, 446" Small Block, Brodix Canted Valve, lenco 5 speed, 7.54 @ 180. mph,1.06 60', 2235 lbs for 2014. GM Canada Docs, Highly Optioned 69 RSZ28 , Hugger Orange, White Stripes, 42,000 mile survivor, owned since 1973.