So I've got 62k+ miles (35k with mods) and I've got some numbers that I thought others might be interested in seeing:

Compression = 220 psi on left bank, 225 psi on right bank

Leak down = <5% on all cylinders

I'm very pleased with the numbers. Anyone else have some for comparison?

 

Great numbers Rich!
Glad she is behavin for you.
I have not tried compression test yet... Hope I do as well.

 

Thanks Mike - she's running quite well these days.

I'd be interested in hearing your numbers whenever you get them.

You going to TX Mile this year?

 

I will be there this weekend. Hoping for the magic number!

 

Good numbers. The 5 psi bank to bank is most likely do to cam timing. I have yet to open a tt motor that the timing was on.

 

Thanks Tim - that is what I suspected.

What other numbers have you seen? I'd like a greater sampling for comparison - I only have a sample size of 1 thus far.

 

Do I need to bring my helmet

 

Honestly I only check the compression on the stand by hand to make sure all is well before I reassembly the rest of the motor. It is common in this motor for one bank to be off, its never a lot. If there is something that I suspect I go right for the leak down. Its more telling of the cylinder condition then a compression test.

 

tim, how many miles do you recommened for break in with new rings and non synthetic oil? also, drive it hard or moderate?

 

Nobody else has compression and leak-down numbers?

Where are all the builders and technicians with their experiences?

 

Decent numbers... Now for your next 60k miles.

 

I will bring the car up to temp 3 times on the lift. then dump the oil through a big coffee filter and check it for metal also cut the oil filter and open all the pleats and check for same. new oil and filter run 50 to 100 miles of excelling with a heavy foot but not standing on the boost. dump the oil again as before, if all looks good you are done. If at any of those oil changes show metal take the motor apart and see whats going on. When I pulled my motor apart the first time it had 70,000 miles on it and there was still cross hatching on the sleeves.

 

i'm glad to see these engines last long

 

thanks tim. when i took mine apart at 61k and changed the rods it also still had the cross hatchings

 

Porsche really did there homework with the sleeves. The counter shaft's bearings always look to be in the worst shape of anything in the motor.