| Overview of build: You can see the engine components for this build in my profile. Long story short, I bought a built longblock from EPR a couple years back for my build. The engine ran seemingly great with good compression across all cylinders. From day one i could see excessive oil in the combustion chamber and it would also travel/revert into my intake plenum. I have a full egr delete so I am not sucking oil into my intake plenum and must be coming from the heads. I had several oil leaks that took me a long time to finally correct. I had to pull the oil pan and transmission and timing belt several times over the course of the first 6 months or so that i got everything put together and running. List of leaks and causes 1. EPR oil pan had weld pin hole that was not pressure tested before i installed it. I had to pull the pan and get it welded on my own dollar.
2. After i installed the oil pan it was still leaking. Pulled the pan again (this time with an engine pull) and discovered that EPR used the wrong half moon gasket.. from what i could tell it was from a 350Z and had a very large gap where it wasnt sealing.
3. Driver side intake cam seal popped out and barfed oil all over my timing belt. Cause was clogged oil return port behind the seal. Looks like the head was not cleaned properly... i pulled out a cured piece of red silicone. I did not use red silicone so it came with the motor...
4. Rear main seal leaking. Pulled the tranny on two occasions and replaced the rear main. Still leaking. Sleeved it on the third try. Not leaking anymore. Leading to current teardown: I put about 5k miles on this build until i started getting bubbles in the radiator. My tune is a standard haltech tune with care put into the AFR tuning over the course of a year or so of driving on the weekends. I would have timing pulled if it registered pinging with a relatively low threshold (even though the pnp haltech and standard knock sensor is not the greatest combination). I pulled the motor apart, took apart the heads and engine block. I noticed that 30p exhaust valves were used on the heads. They are not made from high temperature resistant alloy required by turbocharged engine.. not sure if these are contributing to my issues but im sure it doesnt help. It looks like there might be some oil blowing by the valve stem seals given the look of the chambers.. I would like input on the bore and hone condition of this block. There are scrapes along the piston travel 180 deg from each other on the cylinder walls on all cylinders. I can catch a nail on some of these. The honing xhatch looks very rough.. i am going to take this block to a performance machine shop and have it inspected. I can not tell if the pistons are in ok condition and i need to clean them. I think they were coated with some ceramics, and it looks like the ceramics are pitting and coming off.. There is also excessive skirt wear for 5k miles in my opinion, but this is where i need input from the experts. Also, it looks like my main bearings are toast. I made sure i primed the oil pump on first start up, did the brake in procedure that EPR recommended with the Motul brakein oil, did oil changes multiple times in the first 1k miles. The rod bearings look ok with the exception of one of them. Opinions? The pistons are 88mm and if the bore and hone is toast then i would need to go to 89mm right? The other option is source another block and start from scratch. Can i recondition these pistons? Also, i took off one of the piston ring sets, and one of the gaps looks way bigger than the other. This is the first time ive tore down the Z motor so i dont know all of the tolerances and measurements. I have been doing all of the work on my Z's for 18 years but this is the first block teardown. https://imgur.com/a/6AVuYzZ
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