Did you find out why your engine died yet?

 

No, not yet. I'm just saving money right now. As soon as I find out what happened I'll post it up.

 

i better boost down alittle. that scares me

 

The scoring on the number 3 cylinder really makes me think that the pistons overheated like some others hinted. When you see score marks like the #3 exhibits that is indicative of some serous heat. Most all pistons have somewhat tapered walls with the crown having a smaller diameter then the skirt. The reason for this is simply for heat expansion, the head gets much hotter then the skirts do and as such it expands more then the skirts, the taper is to allow for this expansion. When the crown or head of the piston gets too hot it will over expand leading to scoring, which makes the piston and the wall even hotter, (not to mention that the piston is already hot) and it will induce detonation. It is kind of a nasty self purpetuating cycle.....

This is pure speculation based off of the pictures, but it looks like #2 had already become hot enough to both score the wall and begin to detonate, and that #3 was begining to score but had not quite reached the detonation point yet. I would also think that the guys who posted earlier were on the right track about the oil squirters not fuctioning correctly, normally a water cooling problem will be seen in the #4 piston first as it is last in line for the cool water, #1 will run coolest then #2 ect. I believe that some of the old sylvia's had three injectors that were the same with #4 being 5-10cc's higher capacity to keep #4 a bit richer to help keep it cool. Seems like it was a neat concept to me, but I do not know of anyone else doing this any more...

Anyway, you might want to see if you have something clogging the oil squirters, just an idea though.

 

Thanks. I'll be sure to keep all of this in mind once I pull the motor out.

 

The earliest sign of an overheated piston is not just random scoring, but specific scoring on the sides of the piston where the pin-bosses are. The axis perpendicular to the wrist-pin is too soft to score the cast-iron bore until the piston is waaaaaay overheated (IE cyl #2), so you always see scoring parallel to the wrist-pin first. (IE cyl #3)

Sorry for beating a dead horse here. I figure that information might be useful to someone searching for threads like this in the future.

Hopefully you find the cause of the overheating so it doesn't happen to your next motor! (knock on wood)

-Adrian

 

that is crazy

 

I took a look at the engine pictures. No mystery here. The engine failed from flat out detonation. End of story.

David Buschur
www.buschurracing.com

 

wow, my credit card is burning a hole in my pocket right now from that...haha

but good luck on your rebuild, let us know how it turns out

 

If the car was tuned for 93 octane........Is it possible that fuel of lesser quality caused this(detonation)?

I heard of stories about gas stations mixing crap fuel with 93 octane to make more money...and our refined fuel is not what it used to be due to cost savings...

Just a thought

 

Yes, poor gas is a possibility. I believe in this case though the owner of this car was running race gas in it.

I'd love to have a look at the map that was in the car, if you want to send it to me I'd be glad to give an opinion (privately on it) who tuned it?

David Buschur
www.buschurracing.com

 

I tuned the car. .. It was flash, 20psi of boost , tuned it about a yr ago. He has been to the track / street numerous times since.. Im confused myself. The car was on pump..

From what i can gather , he bounced off the rev limiter in 4th gear .. prob what around 125mph.. then stayed in it ..and hit 5th ..

Mark
Turbotrix

 

Yep that is correct. Barry has been out to the track/street numerous times since the tune. I was behind him playing camera car when this happened. I puff of black smoke followed by barry staying in it then she finally gave.

 

Oh, I thought the car had an AEM in it. I guess I am trying to follow to many posts all at once

I can't help you with the map on a reflash. If you have been running it that long and you didn't just turn the boost up beyond what is reasonable on pump gas then I agree you very well could have gotten some bad fuel.

David Buschur
www.buschurracing.com

 

Pump gas might be the answer......I would take the gas out(if any left) and test it......

During my trip to Europe, I noticed that you can buy simple Octane test kits, water test kits etc...Not sure if you can buy them here(US), maybe E-bay?

Like I mentioned before, gas is not what it was years ago....cost reductions and economic reasons have forced all distribution channels to reduce costs which may translate to producing less standard fuels....Sometimes the justification is emissions reduction(ethanol,methanol etc..)

It's worth a try.......