TypeRman311

So motor just obliterated my motor yesterday lol huge hole in the side of the block probably either dropped a valve or supn rod bearing. I was driving considerably hard on mulholland the snake I hit the rev limiter then completely lost power at first it sounded like tct failure but after a few miles of limping my way home it quickly deteriorated to terrifying nosiness lol. You may ask why I didn't stop well two reasons no AAA and terrible cell phone service​​​.... ****ing t mobile lol. So I made it 3/4ths the way home and literally a hand grande went off in my engine bay! Limping on what felt like 2 cylinders I made it about a mile in residential and it just seized! 6 quarts of oil on the floor, smoke billowing and would not turn over wouldn't move lol. I skateboarded a block down the road and picked up chunks of the block! Probably a rod snapped and rotated Lol first time this has ever happened prrobably not the last but suuuuccckks cause it happened on my beloved pretty clean NFR ap1 with only 87k on the clock.

So im posting becausee I'd like to know the communities input... here's the facts driving extremely hard... yes! I only put top notch oil Lucas racing only, torco and driven motor oil.... definitely amazing stuff almost completey stopped ap1 notorious oil consumption! Engine was well maintained, ap2 updated oil pump, jets and aluminum radiator. Ballade bolt in oil pan baffle.

I figured as a Honda it would be fairly bulletproof but unfortunately even 9k can't stop bullets lol. Here's my questions to better protect my new ap1 swap that I paided so much for ughhh! What is typical longevity of a weekend pretty much track like conditions motor? And how can I potentially prevent my new swap from becoming an expensive piece of furniture lol. Open to all opinions positive or negative I know some of you are gunna be like what an idiot lol but i assure you going fast is extremely addictive! Welcome to an open discussion... I will Post pics a.s.a.p and with the engineer at work (completed formula SAE and a very experienced power train expert) forensically tear down the motor and conclude a failure. His thought was perhaps I bounced in the rev limiter but the motor may have went past 9k by a few hundred RPM because OEM rev limiters aren't amazing. Mean piston speed went through the roof and caused extensive stress on the connecting rod sub assembly. Definitely was a mechanical over rev... I know better and although shit happens in high speed driving I very rarely mechanically over reved... I'll pull the VC and see if I dropped a valve and that will conclude that. Perhaps oil starvation from extreme cornering? any thoughts?

SmokeyGatto

could be oil starvation. I'd do a baffled oil pan, get it valve adjusted, and just change the oil frequently.

Definitely not the limiter, and who knows how the previous owners took care of her.

Also if you dropped a valve and you have ap2 retainers, its safe to say who ever did the install bodged that valve.

bgoetz

I think it might be difficult to make any determination. It sounds like you didn't have immediate failure and drove a bit and then it failed. Had you stopped right away you would have had better luck. If I were to guess based on your description i would say a dropped valve, but that is just a complete guess.

TypeRman311

I pulled off the VC today no dropped valves but when I get a closer look I'll see if I cracked any retainers. I bet if I stopped right away I probably could have saved the block maybe done a stoker instead of a swap about the same price... but yeah thanks for the input, again opinions welcomed and I'll post pics a.s.a.p this would be a good case study and perhaps this could help not only myself but others in the s2k community understand the dynamics/longevity of a heavily driven motor.

TypeRman311

I did have the ballade sports bolt in oil pan baffle and I did a valve adjustment in the beginning of the year, I also change my oil about 4 times a year with premium oil. I wonder the the rod bolts stretched under high revs and caused the spun bearing. And agreed maybe the previously owners may have ran it just as hard as I did. The reason the rev limiter is a suspect is because s2000's are notorious for cam crank synchronization issues that may have been a factor is it possible that it may have been mechanically reved higher then the rev limiter allows, hardware issues, also the software OEM computer may not have been finely tuned which is typically in most OEMs that "just get good enough to drive and we'll update it later" attitude may have been a a unknown factor, a experience s2k tuner may confirm or deny this. OEM's spend a lot of money in engine calibration, and they don't make money till the car hits the dealer showrooms.

HarryD

?????

windhund116

"That may have been a factor is it possible that it may have been mechanically reved higher then the rev limiter allows."

AFAIK, this is only possible on downshifts and not upshifting, as long as rev limiter is enabled. This over-rev can happen in any car, during improper downshifting. Not just the S2000.

Slowcrash_101

Racing oils don't like to sit for long periods, they're fine on track where the oil is going to be hot at all times, and changes happen frequently. They're not so good for a street car especially one that doesn't get driven every day(racing oils deteriorated from condensation and oxidation more than road car oils). For the future I'd invest in an oil cooler, and to use road car oil if you really want to race the engine, but not drive the car daily.

Car Analogy

The rev limiter is not to blame. It cuts in well before any damage can occur. Bouncing off the rev limiter is not going to cause a failure. You could bounce it off the limiter on every upshift and not cause a failure (assuming proper oil level, appropriate oil grade, and no G related oil starvation).

But the rev limiter only works on upshifts. It does not offer any protection on downshifts.

Mechanical overrevs only occur on downshifts.

So if you have a mechanical overrev, the limiter has no ability to protect in that scenario.

freq

Doubtful.

It takes slicks and sustained g-forces for that. That's not happening on the street.

Dropped valve is my bet.

oil coolers add a level of complexity that doesn't need to be there. Plus, they arent always fool-proof and can add another fail point.