[Dyna+]

Originally Posted by Alan340

Nice man. Are those the 82mm or 82.5mm pistons? And what rod bearings did you get? Do they come with the coating that the original ones come from the factory?

The pistons are the CP 82mm 11:1 forged ones. I bought a set of King rod and main bearings. I mic’d them when I was putting them in. The road bearings dont have the same coating as the factory ones but I never run the start stop and I believe thats what the coating is really intended for.

[Dyna+]

Originally Posted by 340iGUY

Wow.
Are you a mechanic?
How did you know how to disassemble this?

Not officially LOL... Ive wrenched for most of my life but not professionally. I have a buddy down the street who is an amazing mechanic and he also works with an ex BMW shop foreman so he’s been guiding me. Also the TIS is a savior.

[Mr. 340]

Originally Posted by Dyna+

The pistons are the CP 82mm 11:1 forged ones. I bought a set of King rod and main bearings. I mic’d them when I was putting them in. The road bearings dont have the same coating as the factory ones but I never run the start stop and I believe thats what the coating is really intended for.

Oh ok cool. Yeah same here, I never run the start stop. I guess you are right, shouldn't be much of an issue. Good luck on the rebuild man. Keep us updated

[Cobra358]

Originally Posted by weehe126

Looking at the pics again I'm pretty sure the lighter color on C5 is actually due to the oil, not fuel. You could always have the injectors tested.

I agree, looks like oil to me as well. Definitely have the injectors tested.

[340iGUY]

Originally Posted by Dyna+

Not officially LOL... Ive wrenched for most of my life but not professionally. I have a buddy down the street who is an amazing mechanic and he also works with an ex BMW shop foreman so he’s been guiding me. Also the TIS is a savior.

You are one brave dude.

[Avaley]

appreciate your willingness to push your car, a lot of the newer cars are still in garage queen status / under warranty.

[BWbimmer]

Originally Posted by Dyna+

Not officially LOL... Ive wrenched for most of my life but not professionally. I have a buddy down the street who is an amazing mechanic and he also works with an ex BMW shop foreman so he’s been guiding me. Also the TIS is a savior.

How are you getting on?

[YeeYeeSupraBowl]

I'm new around and i wanted to follow the thread. Just posting a reply to hopefully keep up. This is very interesting GL on the build.

[hardparker]

If you don't have it put back together yet, you should do yourself a favor and put forged rods in it while it's apart.

[Mr. 340]

Originally Posted by hardparker

If you don't have it put back together yet, you should do yourself a favor and put forged rods in it while it's apart.

Factory rods are already forged. Really only recommended to upgrade them if you gonna push 600+ whp. Pistons are the weakest point from what I know on the 1st Gen B58.

[borderm3]

I am an indy shop. I have a customer with broken ringlands in cylinder 6. I dont know but I am leaning more towards piston/fueling design problem that might only be an issue when making higher power. This vehicle has a ots tune and standard modifications. There is a BMW tech article that details the upgrade on the fueling system on the TU. I suspect they are related as the tu doesnt seem to see these issues.

To positively identify the injector as a problem I would need somewhere that tests not only the output and pattern, but also the time resolved waveform for any irregularities. Based on how these would have to fail I dont think it would be a steady state failure.

[BMWILUVU]

Originally Posted by borderm3

I am an indy shop. I have a customer with broken ringlands in cylinder 6. I dont know but I am leaning more towards piston/fueling design problem that might only be an issue when making higher power. This vehicle has a ots tune and standard modifications. There is a BMW tech article that details the upgrade on the fueling system on the TU. I suspect they are related as the tu doesnt seem to see these issues.

To positively identify the injector as a problem I would need somewhere that tests not only the output and pattern, but also the time resolved waveform for any irregularities. Based on how these would have to fail I dont think it would be a steady state failure.

Can you please post that tech bulletin?

[MD20]

Hey man, any updates on the engine? Is it burning any oil? I want to re hone my engine too, but idk if it will worsen the engine or not? Thanks

[MD20]

Damn, a simple yes or no would've been cool too I am about to order new piston rings for my build too but the BMW ones are crazy expensive! Any alternative? With the BMW Parts number I couldn't find a matching pair. There are however Mahle ones with the same diameter but the reference part number that they give are for the B48 engines? Any help on this would be really cool!

[Dyna+]

Hi everyone,

Quick update here. Crazy story, ended up selling the car to a kid for about a year while I built an 800 hp single cab truck that was, needless to say nuts. Ended up getting rid of the truck and buying the car back from the kid.

It’s been a couple of years now and car is still running strong. I do deal with some minimal oil consumption. I assume largely impart due to the forged pistons. Other than that the motor been great. Had the chance to run the car a couple of track days here in Southern California & had zero issues. The car now has roughly 70K on it and I’ve run a stage 2 OTS map every day since the rebuild and she shows no signs of slowing down.

Next up,TU fuel pump and a flex fuel tune and sensor.

[WrxToBeamerGuy]

Originally Posted by Dyna+

Hi everyone,

Quick update here. Crazy story, ended up selling the car to a kid for about a year while I built an 800 hp single cab truck that was, needless to say nuts. Ended up getting rid of the truck and buying the car back from the kid.

It’s been a couple of years now and car is still running strong. I do deal with some minimal oil consumption. I assume largely impart due to the forged pistons. Other than that the motor been great. Had the chance to run the car a couple of track days here in Southern California & had zero issues. The car now has roughly 70K on it and I’ve run a stage 2 OTS map every day since the rebuild and she shows no signs of slowing down.

Next up,TU fuel pump and a flex fuel tune and sensor.

Its not everyday that OP follows up years later! Thanks for the info and best of luck

[BryanB58]

Originally Posted by Dyna+

Hi everyone,

Quick update here. Crazy story, ended up selling the car to a kid for about a year while I built an 800 hp single cab truck that was, needless to say nuts. Ended up getting rid of the truck and buying the car back from the kid.

It’s been a couple of years now and car is still running strong. I do deal with some minimal oil consumption. I assume largely impart due to the forged pistons. Other than that the motor been great. Had the chance to run the car a couple of track days here in Southern California & had zero issues. The car now has roughly 70K on it and I’ve run a stage 2 OTS map every day since the rebuild and she shows no signs of slowing down.

Next up,TU fuel pump and a flex fuel tune and sensor.

Hybrid turbo in the near future?