I am looking at an 03 Miata to buy. I asked the seller to do a compression test. His results were 120 on three and 135 on the fourth. He says that is normal for an engine with the variable cam. Supposedly the cam advance since it works off oil pressure does not advance the cam enough to avoid overlap of open valves resulting in a false low reading.

Anybody have knowledge of this? I have been searching for a specified compression reading but no luck as yet.

I have also posted on the Miata forum but nobody there seems to know as yet.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.