GreeceS13

Hallo guys..
A friend of me has a forged evo at 20psi with a 6464 turbo...
3rd piston gone...

What do you think about this damage? All the other pistons was ok...
Only 3rd piston...

LetsGetThisDone

iTrader: (1)

Ring land failure on the intake side...That's interesting. Usually it happens on the exhaust side.

GreeceS13

Why it happened?
Timing? Fuel? or just a broken spark plug?

100octane
12.0afr
14 deg timing

I think that it isn't very agresive tunning, right?

The signs are from something broken or detonations?

barneyb

Broken spark plug, broken ring land, I know what I'd say.

RightSaid fred

Another bad tune

LetsGetThisDone

iTrader: (1)

I don't see predet erosion. Possible that the plug broke and broke the piston.


Whether that timing was OK kind of depends on what rpm it was 14* at, and how much boost. And also how much timing it had in other areas of the map. Typically, too much timing at peak torque, or peak boost, or around 4-5k is just as dangerous.

GreeceS13

Timing was around 10* at 4-6 because I know that the engine has a lot of torque there.
And at 7 was 13* and at 8 was 14*
Boost was 20psi.
The engined hasn't a lot of compresion. Only 9.2:1!

The plugs was 8 cold only... I didn't know that... In a car with so big turbo I would run it with 10 deggree plugs only.

The unbelievable is that we found the broken plug in the intake manifold!!!!
How the helll the pieces arrived at the manifold?

So your opinion is that just broke the plug and that's the reason of all this right?
The most signs are just from the broken pieces of the plug right?

RightSaid fred

Everything breaks for a reason.



As I said to a mechanic one day.
His reply........no, things just break.


Your knock control won't be working of course.

GreeceS13

This car has AEM EMS1 and it doesn't have reliable knock control .

TrendSetter

iTrader: (1)

bad tune

GreeceS13

It isn't bad tune... Is was a very safe tune.
It is a forged engine and the timing is pretty low.
100 oct fuel!
Don't tell something if you don't know and also if you don't know how to proove it..

LetsGetThisDone

iTrader: (1)

Timing is a bit aggressive down low, but it shouldn't have caused that. Can you clean the carbon off the pistons, and get better/clearer pics of all of them. Also, pics of all the spark plugs.


You could have had an injector issue that cause that one cylinder to go lean...

TrendSetter

iTrader: (1)

you ripped the ring land off a forged piston. the only way it wasnt a bad tune is if the ring gaps are too tight.
too much timing can blow a hole through the ring lands and cause that same damage. the giant chunk of forged aluminum you just set free then bounced around inside the motor and did the rest of the damage.

RightSaid fred

If it really WAS a safe tune........it wouldn't have broken.

Isn't that the meaning of the word "safe"?

Safe, as in you can thrash it and drive it like you stole it and it'll keep on going and won't break.


As safe as a broken rubber.


You should take lots more photos, pull all the pistons out........put the photos up .