So yeah, pretty sure it's a spun rod bearing.
Entirely my fault >.<
We got up early and I broke in the motor by driving it to the track. I did my best to vary the engine speed and do plenty of engine braking, but it was 70ish miles on the freeway. Big thanks to Pat for driving behind me while I varried the speed from 50 to 70 and back for an hour or so, I'm sure it was quite annoying. Around Morgan Hill it got super foggy and wet and my hands were cold enough that I was happy I didn't have the shift boot on as I shoved my hand in the transmission tunnel
I got to the track and changed the oil right away(I couldn't get the filter off, so just an oil change ). This is where I made my first (second?) mistake. I didn't check the oil level before I changed it.
I ran the first session which was my first time in the full track point by group. It went pretty well. A lot of pointing people by but it was nice to not worry about where I was pointing them by at
. The car felt good. Pulled pretty hard, and while the s-drives felt ok they certainly arn't nt-01s! I had a little off track excursion between 8 and 9 right at the end of the session, but I was able to drive out and the only damage was a slightly bent fender stay that made the fender wear the tire a bit. A few minutes of yanking on the stay and all was better.
My GF went out for her first session a bit after that and I rode with her. She did well (came in to 11 hot but kept it on the track on her first lap) and the car seemed fine too. EO2K showed up after that and we noticed that I had forgot to put the dreaded ac pump mounting bracket bolt in so there was a bit of oil on the bottom front of the block. I checked the oil level at this point and it seemed fine.
We each did two more sessions where we had a session between us and were having a dandy time
Then after lunch we had a back to back session. I was driving in the second session and noticed that I was getting a fair amount of smoke out the exhaust on heavy acceleration and then a lap or two later I heard some odd noise on the hill between 5 and 6. When it made the same noise on the next lap I pulled off.
Once off the track, without the ridiculous wind noise, the noise sounded like rod knock :( I checked the oil at this point and it was barely(if at all) on the dipstick. A quart and a half later I drove it around the paddaock and the back roads to check out the noise without a helmet on. It only made the noise when letting off after free reving and under heavy load.
Obviously the track day was over for me and my GF at this point (we only missed out on 1 or 2 sessions each). When cleaning up I emptied the drain pan in to the old oil bottle and only got 2.5 quarts out. Had I checked before the first change I would have caught the issue then. My parents live about 30 miles from MRLS and since the noise was pretty mild I decided to try to drive it to their house.
About 10 miles from the track the noise was was so bad I just pulled off and called AAA and had them tow it home.
So here's my list of mistakes that I expect lead to this:
- Honed a block that was known to have blow by issues before (this was a calculated risk at least, and I replaced the rings).
- Broke in the motor by driving it to the track on the freeway.
- Didn't check the oil level before changing it the first time.
- Didn't change the filter at the first change. Which means I over filled it by putting in a gallon of oil, which lead to the level being fine two sessions later, when it was obviously consuming oil.
- Didn't check the level between every session (this is possibly the dumbest mistake I made as I could've at least caught the issue and I know that I should do this).
- Decided to drive it knowing there was something wrong (I suspect the rod is trashed now, listening to the noise).
I'll pull the motor in the next week or so (with Pat and EO2ks help most likely) and do a full tear down to see what's broke.
I'll add some pictures later, mostly just a nice sunny 70* Juneuary track day
Is it worth it to do a Blackstone report and see what they tell me?