Cylinder leakage test

[axistang]

What are normal numbers for a cylinder leakage test? We did it on a friends car 6 cylinders were 15% or less. One cylinder was 25% and the other was 30%.

[406malibu]

what was the psi it held at, thats how Ive always seen it done.

[axistang]

what was the psi it held at, thats how Ive always seen it done.

Are you thinking about a compression tester instead of a cylinder leakage tool ?

[rmtt]

I have always heard anything above 30% is where you needed to start being concerned.

[406malibu]

Are you thinking about a compression tester instead of a cylinder leakage tool ?

yea I am, my bad. :screwy:

[axistang]

The rings have to be shot on the car. At least on those 2 cylinders. It runs strong but smokes like a train when the boost kicks in. The seals in the blower are good. It only smokes under boost so that rules out valve stem seals.

[rmtt]

The rings have to be shot on the car. At least on those 2 cylinders. It runs strong but smokes like a train when the boost kicks in. The seals in the blower are good. It only smokes under boost so that rules out valve stem seals.

Sounds like it...that's typically the first place to start looking at when the leakdown test give less than optimal results.

How much boost are you running?

[axistang]

Its the guy that bought my original Vortech. Right now it will only make 4psi. With a pulley change to 10psi and an aftermarket intake manifold it has a 7.2@95in it but he needs to get it to stop smoking first.

[trophystock]

less then 10% is OK with 5 to 6 % best.