what should compression be

[baedriver]

Just wondering what the compression should be on a 1997 Gt-40 EFI

[Mikeski]

RE: what should compression be

Are you eagledriver from mbo?

http://www.correctcraftfan.com/ftp/new/PCMsvcmanual.pdf see page 138, 105-140psi. It is not specific to GT-40 but I believe this applies to almost any V8 since I have read almost the same thing in a Chilton's for a Chevy truck motor. Higher compression engines should have a slightly higher reading. The new Chevy's have 9.4:1 compression, the manual specs are 130-160psi.

I thought the GT-40 manual was somewhere on the site but I didn't see it. I gave mine to the buyer of my 1995 thinking I could print another anytime.

[baedriver]

no what do you mean by eagle driver thanks for the post

[NautiqueJeff]

Re: RE: what should compression be

I thought the GT-40 manual was somewhere on the site but I didn't see it. I gave mine to the buyer of my 1995 thinking I could print another anytime.

That manual is on our site.

http://www.planetnautique.com/index....q=getit&lid=22

[magene]

Somewhere along the way while I was checking out used boats to buy I read (or was told) that the compression needs to be not only in the range mentioned above but all cylinders need to be within about 5-10 psi from the lowest reading to the highest reading. Made sense to me as a wide range would indicate uneven wearing. I bought a 2000 SAN with all readings within 5 psi and am very happy so far (knock on wood).

Hope this helps - Gene