Stock cylinder wall? Nikasil finish?
12-30-2014, 01:40 PM
#16
Burning Brakes
Thread Starter
Inrev, I just went through a major overhaul of another engine with Nikasil coating on the cylinder bore (no liner). A (bad) concept that was tried by some engineer years ago...The cross hatched portion of my cylinders looked good, however, I had pitting of the coating as well. Your second picture looks a lot like my cylinder.
So, I had some good cross hatch section and some bad pitting. Outcome for me was, high oil consumption, and loss of compression and low power when things got nice and hot. I had to purchase new cylinders as this was a high performance no liner concept. Not sure if this helps, but if I am seeing pitting in your liner then that is bad. Typically caused by water / condensation and or engine not run often, as I was told.
(not GT3 engine...but similar). GL
So, I had some good cross hatch section and some bad pitting. Outcome for me was, high oil consumption, and loss of compression and low power when things got nice and hot. I had to purchase new cylinders as this was a high performance no liner concept. Not sure if this helps, but if I am seeing pitting in your liner then that is bad. Typically caused by water / condensation and or engine not run often, as I was told.
(not GT3 engine...but similar). GL
12-30-2014, 05:07 PM
#17
12-30-2014, 05:51 PM
#18
you can replate them, but IMO I'd just buy the new liners(liners are separate from the cylinder casing/waterjacket on water-Mezger) from Porsche and have a bit more peace of mind.
12-30-2014, 06:07 PM
#19
Trucker
Rennlist Member
Rennlist Member
OP, your cross hatch in the photo looks ok to me. And your dealer can measure the bore versus speculate. Is the engine apart? If you have liner damage your compression will be low as well. Anyhow, it is hard to tell looking at 3 pix. GL.
Yes. And in my case I could have but chose to go bigger bore and changed other parts...
Yes. And in my case I could have but chose to go bigger bore and changed other parts...