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Sanity check.

I've got a 2180 VW that I'm putting together. Came from Great Plains back when Marty was there. I'm at the point of setting the compression. Measured deck height without shims has the piston protruding from the cylinder .070". Adding either .296" or .306" in shims would get me to ~7:1 compression (7 or 7.1) I am curious what the community thinks about that amount of shims. It just seems like a lot. I have an Aerovee that only took .060" in shims.

Maybe this is normal and within spec? I really don't know. Thoughts?

The Aerovee manual has a chart with a range of .16 - .32 in shims for 7:1 compression depending on how the deck height measures out. This includes 0.06 for the (copper) head gasket. Seems like you're in a similar range.

The Aerovee assembly manual shows a total of .31in of shims for that compression and deck height. That's assuming a 55cc cylinder head.
Remember, out of that .31 total, .060 is the head gasket. So that's .250 at the cylinder base.

Rynoth wrote:The Aerovee manual has a chart with a range of .16 - .32 for 7:1 compression depending on how the deck height measures out. This includes 0.6 for the (copper) head gasket. Seems like you're in a similar range.

I'm sure Ryan meant .060.

Based on my deck height measurement (neg .002) the aerovee turbo manual suggests using .09 + .04 + .04 shims along with the head gasket to get 7:1 comp ratio. The kit only comes with one set (4 total) of .04 so I used the .09, .06 and .04 for each cyl. How critical is the choice of shims and will i be ok using a .06 instead of the. 04.
Peter