incorrect if its black smoke fuel is the cause, oil burns blue.

 

no, its entirely possible. as motors get to middle age (lol) they accrue carbon in the cylinder which takes up space and can raise compression a bit. my first ls motor had like 210k on it when it was boosted and its compression was right about 200. i boosted it till it had like 240,000 miles and it was down to 160psi hence i replaced it, because 160 was low and it was starting to consume fluids.



whats the tune on this motor man? dont be ignorant and sit there and say thats its just oil. yes bad valve seals drip oil and that burns off but it wont necessarily show up on a compression test because the valve is closed hence it wont lower your compression. if the intake seals are leaking then its possible the top of your pistons will appear "wet" if u look through the spark plug hole.

maybe running rich over time has done it toll on the crosshatch. whats the tune look like? do a leakdown test.

 

This one above. The engine started to cool off. That's why it's a little low.



But to answer the questions. I changed the head gasket when I put the head on. And the head is completely rebuilt from a shop I trust. Even had a second person come check it out. The valve seals are not leaking. And the ecu is just a stock p28 for now until I get it tuned. Yea it is running rich but it only has about 1000 miles on the head since it was rebuilt. And no I do not have a wide band on it. My buddy hooked his up and it was running rich.

 

Was that ^ with the throttle wide open? And how many revolutions?

It usually takes 5-10 revolutions of the motor to show max pressure.

 

Yes this one was @ full throttle. At 4 revolutions the were all at 150. These pics are all at 10 revolutions. Except the lower one of the 4 is only at about 7 revolutions because the battery was dying and it wouldn't keep cranking. (It's been a while since I drove the car so it didn't have a good charge on it.)

 

ok lets really get down to some truths here. how do you know its running rich? that smoke you see is probably burning oil.

you are running a stock p28. why. with the o2 sensors installed and operational its running around stoich when cruising. on cold start and high load/wot its using just the ecu settings, which are mapped for a motor that has like 20% less displacement and no where near the cfm of your lsvtec. my bet is its running real lean causing damage. stop messing around the the compression and do a leakdown. wouldnt be surprised if you find you are loosing % to the crankcase through the rings.

anyway you already said on the other page that the block is pretty raced out and it does burn oil. start looking for another block and take it easy driving this one so it doesnt let go before you get a replacement block ready to go. put the arp replacement studs in the rods on your new block they are cheap and will allow the block itself to rev deep into the 8000 rpm range. good luck