Compression Check
 

I am in the process of selling my perfect 1982 SC. The buyer wants to have the compression checked. Can anyone tell me what acceptable values would be? Thanks

Good question....I'm shure others will respond shortly, but you'll want to get a percentage of all 6--which is an average distance from the lowest reading to the highest reading. It will be those 2 that will effect the engines capabilities and longevity if they are too far from eachother.

Luck.........s in VA

170-180 on a normally aspirated engine, as I recall ... leakdown within 2 to 5 percent. Turbos are lower compression, but leakdown should still be as low.

Vic
88 Carrera

The Bentley manual for 78-83 911SC specs on the last page that a "new" engine should have 130psi? Doesn't sound right, but that is what is says. My car was measured recently (78 911SC) and all six were at 150psi. The compression ratio for the above years is 8.5:1.

Tony
'78 911SC