Stock F20 with new 2mm gasket. Warm motor with throttle 100% and pulled fuel pump fuse. Dry and Wet (half cap of oil in cylinder). Cranking roughly 8 times. Average of three measurements for one reading.

Dry Wet
#1 - 170 - 195
#2 - 172 - 202
#3 - 182 - 220
#4 - 190 - 217

I think it's time to face the facts...

 

sounds like scored walls or worn rings?

 

leak down test shows 20% or less on all 4. im happy again.

 

Isn't it supposed to be 5% or less leakdown?

Why do you have a 2mm HG?

 

looks like theirs too much variance between the cylinders, did you use the thick head gasket in plans to go turbo?

 

sorry, back from dead. but thought i would update.

car is boosted with a 6265. had a 3m gasket on which blew of course. gave the cometic 2mil gasket a try. during install cyl wall damage was not evident. after the compression test/leakdown i brought the car in to get tuned again. has been running strong ever since. I think my rings are showing some wear. wont have the car running again until spring. sucks living in a state (WI) where you can only drive the car half the year.

 

should crank 4times

 

WRONG!

 

try cranking it for 8. But more importantly look at the gauge, see how quickly it shoots up after the first compression cycle. Did you do cyl#4 first in the test??

 

at the time of performing the test, i was paying attention to the gauge. that's why i said roughly 8 cranks, was kinda counting in the back of my head but could be off a crank or two. i dont remember what cyl i started on. this was done early this year some time.