I have a 78 280z and have taken the compression on all cylinders. All cylinders are 148 - 150 Lbs except the number 3 which is 138 Lbs. Is 1150 Lbs normal and is my range from 138 to 150 OK?

Hi widg

I just did the same with a 77 a couple of weeks ago and got 150s with one 152, the milage was 73,000 at the time.

If you check the search for compression you may have some luck or google Atlantic Z in their tech tips under engine there is a detailed process for compression testing and a bunch of one liners on likely meanings of results.

Good luck.

SB

Your range sounds fairly typical depending on the mileage. The important part is that the diffrence between the measurements for each cylinder is no more than roughly 10%.

Hi, I dont have any time to research this, so I asked you guys first. I need to know the stock thickness of the head gasket on my 77' 280Z. I want to order my nismo head gasket and I need to know which would be closer to stock; 1mm or 2mm.

Thanks for your help.

Brendan