This one's for Doc, or anyone in the know. I'm curious as to how much a /6 block can be milled while still maintaining it's strength and rigidness. I'm guessing .100 is not out of the question.
Tom

sschultz@telusplanet.net

I took ".145 off the deck of my daily driver. you will need shorter pushrods!

beardliz@msn.com

The SL6 block deck is .375 thick in the thinnest locations, it gets up to .500 in some areas.

.100 to .125 off the block is reasonable but you are weakening the structure as you remove material. (by how much is the question) Lots of other engines have .250 deck thicknesses but these are smaller (shorter) heads.

This is a good question and is best answered along with knowing the compression ratio. I personally think that .100 off the head and .100 off the block, everything else "stock" and well assembled (flat / clean surfaces) works fine. (gets you close to 11 to 1 compression with decent head gasket life, depending on all the other work done of course)

For me, I strive to keep the decks thick and strong. I set my compression with the pistons and con rods and use the deck surfaces for sealing and adjusting quanch / squash area clearance, not for developing additional compression.
DD

Thanks guys, the reason I am curious is that I am about to pursue the same path a Andrew with his turbo /6. My plans are to use a 198 with 2.2 turbo pistons. My large valve ported head was already shaved .100, so I figured that the 198 with it's taller piston height would accomodate this. Plus I figured it would rev a little better as well. With a little math I should be able to adjust the compression back to around 8 to 1. This has been an ongoing project for a while. Just getting all the neccesary pieces(turbo, water injection, intercooler, bov, boost controller etc) has taken a while. Mine will be a bit different in that I am using propane on a blow through. I want to go with heavy boost as well, so the block strength and head sealing are very important. Sorry for the long winded response, but I thought that there might be a few interested parties out there. I'll document my successes and failures for others to hopefully learn by.
Tom


sschultz@telusplanet.net