I learned the hard way about who you let bore your block.
This guy (Shop #1) had done good work in the past, and probably can still do good work.
He said the deck was nice and flat, so he didn't mill it. All the pistons were at different heights. So I took the block to a different shop. Shop #2 said the block deck was like ocean waves. A quick mill and now all the pistons were the same height. (we milled the tops off the pistons to achieve Zero Deck) The bores were fresh from Shop #1, So Shop #2 left them alone. Not only were they not round and not straight, they were 0.002 undersize. This plays havoc on the rings. To make things worse, the rings were wrong from the start thanks to the piston manufacture that evidently doesn't know or doesn't care.
Amazing the power difference when everything is right like it should be.
Truth is I was very worried upon initial startup this time when the breather was pumping out smoke. After some "HITS" in the parking lot, that cleared up some, and after a few runs down the track, it cleared up almost completely. So yes, bore finish is very critical. And Shop #2 is familiar with the Total Seal ring package, so that all worked out.
I also did not go way overbore. I'm only at 0.080 over. I considered partial fill on the block, but I ran out of time last year before racing started, so I just went with it. And for this year, why change it.
Anyone have data on the weight of the block filler vs water?
So I agree Seymore: Cylinder strength, straightness, roundness, size, and finish are more important than big cams and carburetors, or at least first on the list of stuff to get right.
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