924Board.org

[MikeJinCO]

How much can the block be milled before running into cam timing problems? Looking at maybe .013 to .015 inch.

Are any offset cam pulley keys available?

We have had to already mill .006 off the head.
_________________
Mike


'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

[Fifty50Plus]

Dan (Ideola) has a compression ratio calculator on his site that shows various amounts of shaving possible and the resulting CR. There is a minimum thickness for the head since the valves already stick out and a maximum that can be taken off the block based on that.
When I shave my blocks (to the max on Dan's page) it winds up exactly 1 tooth on the cam so it isn't retarded. I did see somewhere though that Dodge has offset keys for their old 4 cylinder cars from the '80s - '90s.
_________________
1979 924 NA race car H-Prod SCCA
1982 924 NA race car - Sold
1981 924 Turbo sold
1982 924 Turbo sold
1972 911 E race car - traded for Cayenne Diesel
1975 914 1.8 Building for H-Prod SCCA

[Rasta Monsta]

Also, there is a wide selection of Mk I Golf adjustable pulleys available.
_________________
Toofah King Bad

• WeiBe (1987 924S 2.5t) - 931 S3

[ideola]

As far as I am aware, there is no wear limit specified for the block. In my experience, you don't want to take the block too much below 231mm, measured from the bearing cap mating surface to the head mating surface. If you need to go below 231mm, you can compensate with a thicker Cometic head gasket. The compression ratio calculator is here, and THIS PROFILE will give you the starting point for a US-spec S1 build. You can specify different block heights and Cometic gaskets to see how it works out, and how much piston to deck clearance you'll end up with.

I also have an adjustable cam sprocket:

_________________
erstwhile owner of just about every 924 variant ever made