Hello all!
WARNING! WALL OF TEXT INCOMING! Tldr at the bottom
Backstory:
I bought my 07 speed 3 as a project back in 2021. Previous owner gave me two torn down engines, a trans, and the rolling shell. My dad and I (who has alot of experience with this stuff, not speeds specifically) rebuilt it in the garage. After measuring things out, the block looked good (bore and deck) so we did a quick ball hone on the cylinders and decided on factory sized 87.5mm Manley pistons (and rods) and it ran fine from what I could tell for awhile. Kept the car on the ko4, gathered parts, autocrossed it, dailied it, but in 2023, I got a leakdown tester on it after working through high crankcase pressure issues (almost burned the car down with all the oil pushing through my oil cap breather at autocross... Probably a gross exaggeration but it was still scary lol) and saw 30% leakage in cylinder 3 into the crankase (2% cyl 1, 8% cyl 2, 6% cyl 4) We Borescoped the cylinders and saw major wear so decided it was time to rebuild the bottom end again
Second rebuild!
Got the engine out and block tore down, and man! The pistons fit really loose in the cylinders! I measured the piston-wall clearance when I put it together the first time but dont remember it looking like that! There was also a strange "leopard print" pattern in the cylinders that kind of concerned us. But after talking to our local machine shop guy (old, wise, and grumpy as they all should be...) he assumed I measured the bore wrong, and I believed him. So we decided to bore it out to Manley's 87.75mm pistons and threw it back together, this time with a CST4, big top mount, removed my breather and went dual damond catch cans, etc... And a versatune profile from yours truly! Aaand she ran fine for awhile...
Third rebuild.....
Well a few weeks ago I found massive amounts of oil in my intake. Once again, high crankcase pressures... This time it was pushing oil through my catch cans into my intake system and even blew huge clouds of smoke out the exhaust a couple times! So we did another leakdown and saw 20% leakage in cylinder 2 into the crankcase. Time for another rebuild...
Present time:
Dad and I got the engine out and tore down again. Cylinder 2 had heavy scoring on the wrist pin side and the rings were kind of grooved along the mating surface so the current diagnosis is the engine got something in it like dirt or carbon (or maybe some walnut shells from when I cleaned the intake valves...). But the other cylinders had that same leopard print from the last rebuild too.
Current plan:
I plan on switching from Manley 2618 pistons to mahle 4032 pistons, get dry sleeves installed from LA sleeve (local), and pray to the lord almighty that she stays together! Prob request consulting service from freek too. But, before I go through with everything, I'm hoping to glean from the experiences of others here
P.S.
I've been wanting to make a build thread but have been really bad about documenting and taking pictures... One day...
TL;DR
Has anyone else experienced "leopard printing" on their cylinder walls?
Has anyone else experienced poor longevity from Manley 2618 pistons? (if you go through my whole post, your conclusion will probably be its my fault, but I still want to ask)
Pics incoming!
WARNING! WALL OF TEXT INCOMING! Tldr at the bottom
Backstory:
I bought my 07 speed 3 as a project back in 2021. Previous owner gave me two torn down engines, a trans, and the rolling shell. My dad and I (who has alot of experience with this stuff, not speeds specifically) rebuilt it in the garage. After measuring things out, the block looked good (bore and deck) so we did a quick ball hone on the cylinders and decided on factory sized 87.5mm Manley pistons (and rods) and it ran fine from what I could tell for awhile. Kept the car on the ko4, gathered parts, autocrossed it, dailied it, but in 2023, I got a leakdown tester on it after working through high crankcase pressure issues (almost burned the car down with all the oil pushing through my oil cap breather at autocross... Probably a gross exaggeration but it was still scary lol) and saw 30% leakage in cylinder 3 into the crankase (2% cyl 1, 8% cyl 2, 6% cyl 4) We Borescoped the cylinders and saw major wear so decided it was time to rebuild the bottom end again
Second rebuild!
Got the engine out and block tore down, and man! The pistons fit really loose in the cylinders! I measured the piston-wall clearance when I put it together the first time but dont remember it looking like that! There was also a strange "leopard print" pattern in the cylinders that kind of concerned us. But after talking to our local machine shop guy (old, wise, and grumpy as they all should be...) he assumed I measured the bore wrong, and I believed him. So we decided to bore it out to Manley's 87.75mm pistons and threw it back together, this time with a CST4, big top mount, removed my breather and went dual damond catch cans, etc... And a versatune profile from yours truly! Aaand she ran fine for awhile...
Third rebuild.....
Well a few weeks ago I found massive amounts of oil in my intake. Once again, high crankcase pressures... This time it was pushing oil through my catch cans into my intake system and even blew huge clouds of smoke out the exhaust a couple times! So we did another leakdown and saw 20% leakage in cylinder 2 into the crankcase. Time for another rebuild...
Present time:
Dad and I got the engine out and tore down again. Cylinder 2 had heavy scoring on the wrist pin side and the rings were kind of grooved along the mating surface so the current diagnosis is the engine got something in it like dirt or carbon (or maybe some walnut shells from when I cleaned the intake valves...). But the other cylinders had that same leopard print from the last rebuild too.
Current plan:
I plan on switching from Manley 2618 pistons to mahle 4032 pistons, get dry sleeves installed from LA sleeve (local), and pray to the lord almighty that she stays together! Prob request consulting service from freek too. But, before I go through with everything, I'm hoping to glean from the experiences of others here
P.S.
I've been wanting to make a build thread but have been really bad about documenting and taking pictures... One day...
TL;DR
Has anyone else experienced "leopard printing" on their cylinder walls?
Has anyone else experienced poor longevity from Manley 2618 pistons? (if you go through my whole post, your conclusion will probably be its my fault, but I still want to ask)
Pics incoming!
