tl;dr at the bottom
The Back Story
After 26 years on the road, 220k miles, one year of my ownership, dozens of autocrosses, and one track day, the original, tired, and untouched 4AGE in it finally called it a day (I think). I finally took the MR2 to a proper track day, but apparently it wasn’t quite ready for that. I’m not quite sure what the problem was, but in my first session, it started overheating and cut out a few times, so I pulled into the pits early. I waited for it to cool down, and was planning on doing the next session. The overfill tank was boiling, but this had happened once before, so I wasn’t too terribly worried about it. That time was on a very hot day when it was idling for a very long time between autocross runs. I wasn’t able to recreate it since then, so figured that I just pushed it too hard and decided that I’d take it easier on the next session instead of pushing at 100% the whole time.
For the second session, I kept my eye on the oil pressure and water temperature, and for the most part shifted way earlier. This seemed to be working. The water temperature was hovering a little above where it normally sits, but nothing major. It was maybe about 2/3 up on the gauge while normally it’s sitting at about half. I figured that that was fine, so kept going and just kept my eye on it. Towards the end of the session immediately after I passed the pits, smoke started shooting out of the vents and engine compartment, the temperature needle immediately pegged itself, and the oil pressure dropped. I nursed it back around being careful to stay off of the racing ling and managed to coast back into the pit area where it continued to boil and spit fluid everywhere. This time it looked like the fluid was coming out of the water pump, which had also happened once before when the car was overheated. I wasn’t super worried, but I knew at that point that it wasn’t going back out and that I would be riding home with AAA.
I called AAA a bunch of times, they were unable to find anyone willing to pick me up at the track and drive me threee hours home, so fed up I decided to see if I could nurse it at least part of the way home so that hopefully the next time I call I’ll be in a more populated area. I tried starting it, but had no luck. It almost sounded like the starter was going bad or there wasn’t enough juice to crank it, which should have been a red flag, but I wasn’t thinking very clearly at this point. The track day was long over and the track was closing up, so I asked them to tow me out to the front gate to hopefully continue waiting for a tow truck. While being towed, I decided to try force starting it by bump starting it. It worked, but the engine sounded really, really bad. I said “fuck it” because I really, really wanted to just go home at that point. I was going to take my chances and see how far the car would take me.
The problems started pretty quickly. It was overheating again within a few miles even though I was now driving in a straight line in fifth gear at about 2500 RPMs, so I knew that the car was pretty royally fucked. Unfortunately, the track is in the middle of nowhere, so I didn’t want to just stop. What was I going to tell the tow truck driver? “Umm, I don’t have an adddress, but I’m between some of the construction barriers on Bee Line Highway on the 30 mile stratch between Jupiter and Indiantown.” Yeah, that wasn’t going to happen. Nope, I just had to keep going.
Many nerve-racking miles later, I made it to Indiantown. The engine finally died intirely just within sight of the first gas station, so I coasted in there billowing even more smoke than before. I opened the engine lid to find that some of the tape on parts of the engine had managed to catch on fire because of how hot the clock was, and steam was coming from every place that it shouldn’t be coming from. It was coming out of the valve covers, the spark plug holes, the side of the engine.... Pretty much if there’s a gasket there, steam was coming out. The distributor cap started to melt because of the heat. I called AA again, had better luck, and eventually got it home where it’s now sitting dejected in the street.
The Track/Possible Problems
The track I went to is Palm Beach International Circuit. It’s on kind of a narrow plot of land, so alot of the turns are long and slow. Basically, there are four turns that are about 180 degrees. Three of the four are right handers and the other is a left. Here’s a photo.
What I think might have been part of the problem is the number of long right handers. The 4AGE in the MR2 has a transaxle setup identical to that of a FWD car except at the back and the oil pickup location is on the right hand side of the engine. I do not have additional baffles installed in the oil pan, and I can’t help but wonder if there were problems with oil starvation that caused everything else to go to hell. I also can’t help but wonder what to do now. Obviously, alot of damage was done. The question is whether it’s worth it to even look at the original engine, or if I should just spring for a silvertop swap. I get the feeling that if the engine’s savable at all, it will need a total rebuild, which might end up being more expensive than just doing a swap, and that’s assuming that I didn’t damage the block and internals. What do people with better mechanical knowledge than me think? Would you consider steam and oil shooting out of pretty much every gasket to be that the engine’s completely shot? If so, is it worth even keeping to try to rebuild myself on my own time, or do you think that I now have a decorative engine block sitting in my car?
tl;dr Version -
I (probably) blew the engine in my MR2 because of oil starvation and then overheating it like a dumbass. Think it’s completely blown, should I bother attempting a rebuild, or silvertop swap?