Not enough vacuum

Hey hi All !

The question to follow is :

Is why would anyone put a p90 head on a NA dished n42 block?

answer:

I was in a rush to get a car up & running. now that I got that out the way .

facts:

1980 280zx California model (no egr) with no history of oil consumption

new timing chain (yes I checked the marks & counted 42 links shiny to shiny), fresh p90 head (studded), checked block throughly for vacuum leaks, brake booster good compression test 165 175 wet all same & not enough diifference to warrant rings.

Symptoms: only 7 inches of vac. not enough for fuel pressure regulator to control overich condition car runs@exact timing marks 10 BTC, have also tried advancing cam to #2 & #3 positions on cam sprocket no difference,have even advanced cam sprocket 1 full tooth (it still runs). :stupid:

any input is appreciated

Thanks

Edited April 9, 200916 yr by maxxwell
more info