Engine pull party this Saturday

[GlennCMC70]

The bearing is thicker than the piston to head clearance. If it stacked the bearings on one side of the crank, the slop in the clearances would allow the piston to hit the head.

[Pranav]

This makes sense. Basic timeline of what went down

1. Show up to TWS, go out on track at 50% to heat cycle new Toyos
2. Pull in and hear light tapping from 2k RPM that goes away at 3k
3. Me Glenn Casey and others listen, we think it could be rocker noise or a cam bearing
4. Decide to go back out anyways (doh!), tapping gets real loud until motor starts lugging bad, clutch in and motor shuts itself off

Couldn't turn motor over with starter until I got it home and pulled the plugs, drained water from #8 (pass rear most cyl).

So it looks like what Glenn said, badly spun/stacked bearing, starts hitting head, head lifts/deforms enough to start letting in water, motor hydrolocks; that one piston/rod was obviously fubared, but I also have two more spun rod bearings. Unsure if those two additional ones were caused by the first one and the motor getting waterlogged, or if there was an overall failure of oiling that started spinning bearings in the first place.

We used Clevite "P" bearings, which I understood to be sufficient for what we do. Not implying that bearing choice would've caused this, but since I'm starting over again, what bearings should I run and how loose? The Clevite K bearings seem like a nice upgrade but pricy.

Pistons will remain 20 over with sealed power units + rings, I only have to replace the one damaged one.

[Pranav]

Swung by the shop to drop some stuff off; since I was between office visits couldn't stick around and inspect/ask too many questions.

I glanced at the offending rod/piston and there was a little marring from where it was smacking the head, but the entire skirt/wrist pin area was destroyed and partially missing from the force of the spun/stacked rod bearing shoving it into the head. The head barely had any marring on it as well, so the shop vacuum tested them and is good to re-use it.

Looks like the piston took the brunt of the head impacts and destroyed itself, all without hurting my cylinder wall and head! I guess it was still nicking or blowing out the headgasket which caused it to fail.

Still no "official" word on final damage tally and possible causes; should a call from them soon and will know how to proceed with the rebuild once the crank and rods arrive tomorrow.

Very lucky to be able to reuse my block and heads, and overall very happy that it will be "cheap"

[Hood]

You might want to use ACL race bearings. On an NA motor you shouldn't need to coat them (PolyDyn) but I would make sure that they are running at least .0018 to .002 rod and main clearances. Also make sure that they true the crank journals...even if they have to go .010 or even .020 under, it is better to have a completely round journal (and your bearing speeds are lower as well).

BTW, what shop is doing the work for you?

[Pranav]

Westside performance and machine.

I talked to them about bearings and we settled on Clevite H, along with fresh ARP bolts all througout. Am I missing much on Clevite vs ACL Race? Thought they're both owned by Mahle now...

Everything has been checked and cleaned up at this point, they're hoping to squeeze me in this week so I get a motor to put in next weekend.

I'll talk to them about the clearances and cleaning up the replacement crank (used) on Tuesday before they start, thanks Gary.

[Pranav]

Got so busy with with work Tuesday that I didn't get a chance to call them 'till today. Long story short they already checked and polished the crank; it's in very good shape and are going with it as is. I'll look into grinding the crank and undersized bearings next go around. I'm 28 years old right now, hope next time I go through this I'm well into my 30s.

They're moving along with the motor to try get it back to me Friday. Gives me all of this weekend to get it in and running, next weekend to dyno and autocross it enough to declare it ready for Hallett...