Try to make this summed up easy as possible.

I have a 03 evo 8, fully built. Last year, during a road course event, i spun a rod bearing. My engine was built already with about 25k miles no issues. E85 with spark tech, FIC 1450's, fp red with all the supporting mods making 550whp. Got a new built shortblock, went with the new ss fp black and stock intake mani ported. That is all that i changed from my last build, no issues for 25k miles on that setup.

Ever since my new build, I've put on 400 miles and need new pistons and a bore. The first 300 miles, i blew a spark plug which also took out a valve. I got new valves in a week later, switch to iridium plugs, maybe put on 75 miles. Went to go get a dyno tune, first pull on the dyno. She eats another plug. Now my cylinder is down 25% compression. Haul it home tear it apart to find out i need new pistons now. I also noticed my crank timing gear got stretched over 1mm, i didn't think this would be the issue to cause such a problem but you never know either.

I've talked to a few different people and thinking its gotta be injector failure. Weird thing is i just had my injectors flow tested before my new build. These injectors ran perfectly fine on my last setup for 25k, bought brand new 5-6 years ago.

When it blew the second spark on the dyno, the tuner told me he's had injectors causing issues on customers cars, spending lots of money on new parts only to have the same thing happen again. They've sent those injectors off to the manufacturer to get tested and the results came back perfectly fine. They throw in a new set of different injectors and he's perfectly able to tune the car now.
I pulled my evo engine probably damn near 7-8 times so i know where every bolt goes and what not. its definitely not my first time. I bought new ID injectors, new coils, and getting my shortblock rebuilt.

I have many different pictures to show. One weird thing i noticed is the fuel spread across the pistons is a bit odd. starting at cylinder 4 to 1 getting hotter and hotter it seems. I have a FPR, 450 with a rewire but stock fuel rail and lines, but never had an issue on my fp red on 35+ lbs of boost and my black was only on wastegate at 20lbs.

The last thing i was is to have another brand new shortblock getting eaten again.

 

I have a tool that will allow me to flow test injectors- Have you ever seen it- it is OTC 3398.

If you watch scannerdanner videos on youtube you will see how it works. Search for "scannerdanner fuel injector balance test"

You can test the injectors in the fuel rail while they are installed in the car.

 

Too much CR, not enough fuel, too much timing = pre ignition.
That's what killed the plugs.


What's the CR supposed to be?
What is it really?


Likewise you probably don't know if the fuel pressure is right or not.
You didn't mention the pump or FPR?
Only "stock fuel" whatever that is........apart from not enough.


Looks like a SD tune?
Stock ECU or aftermarket?

 

check out this video- it shows a similar condition where there are differences in the injectors

 

Yes, I have FPR, 450 with a rewire. Stock fuel RAIL is what that sentence is suppose to mean. My buddy tunes at TSM in Atlanta and he sent me a base map before the first blow out even. How could I not have enough fuel when my old setup was using that same exact setup at 35+lbs. I'm only in wastegate pressure.

Speed density on stock ecu

 

was the car detonating?
did you log any in evoscan?

my diagnosis:
not enough fuel, detonation.
Tune/fueling related.

 

Based off all the e85 notes ive read. Its knock resistant as hell. Id have to say it was a fuel pump issue. Since its not just 1 cylinder to blame a injector.

 

The damaged pistons are the 2 farthest from fuel feed line. Looks like the pressure mightve been too low on cylinders 1.2. Just a thought. But youd figure all 4 injectors would have equal fuel pressure/supply in the rail.

 

Being resistant to knock and resistant to pre ignition are 2 different things.
Pre ignition is silent.
A base map for a low CR engine won't work with a high CR engine. Too much timing advance.

That's why I asked about the CR which you haven't mentioned yet.

 

Saying knock,detonation,ping,pre ignition is the same thing. Different ways to say it.

 

The compression ratio is 10:1

 

Wrong.

Knock happens after the plug fires, you hear it with a knock sensor. It shatters the ring lands on factory pistons.
Sustained knock becomes pre ignition as the piston gets hotter and hotter.

Pre ignition is where the fuel starts to burn (auto ignition) before the plug fires.
It's silent.


All alcohol fuels will suffer from pre ignition if run too lean or with too much timing advance.
The end result is melted plug electrodes, broken ceramics and melted pistons.

As per your photos.

What's the difference between a MON rating and a RON rating?


So it's a 10 to 1 piston?
But what is it really?
As in measured.
For all you know it might be 10.5 or 11.0

 

What do the rod bearings look like? Your engine has classic signs of knock/detonation damage. Either too much timing, or running lean.

Knock and predet are indeed different. The correct terms are actually detonation (knock) which is where unburnt fuel/air violently ignites after the main combustion event. And, pre-ignition, which is when the fuel/air charge ignites before it supposed to, usually due to heat, or an over heated spark plug tip, due to the afore mentioned heat.


This article does a good job explaining the difference. If you read the whole article, you'll see why pre-ignition is a silent killer.


http://www.contactmagazine.com/Issue...ineBasics.html

 

no such thing a pre det.

Wiki is better.

 

I didn't say there was no such thing as pre-det.