Serious HG failure on a built O-ringed 2L.. possible cause? (Pics inside)
Interesting re-read. 6* on a 10.5:1 motor at 42psi down low and 18* out the top seems a tad reckless, especially in the face of 4v knock spikes. The other thing no one is asking about is what heat range the plugs were and if they were projected or not.
I have all the data from this car now from Pete. It had 1* down low and 17* at 7700RPM then 18* at 8K~.
From my experience that is fine and would never cause this to happen on this particular setup timing wise vs boost pressure. What caused this to happen is the car was forced more fuel the higher RPM it went even though it was on a MBC and the boost was falling off.
33psi at 7500RPM
27psi at 7800RPM
26psi at 8000RPM
It ran out of injectors and the tuner kept forcing it more fuel via adding more fuel at higher RPM. That is the first sign of a fueling issue, when you have to add more fuel at higher RPM vs take it away even with the boost dropping.
Not to mention as the fuel was being added the AFR didn't move but the IDC kept increasing. It is still irresponsible tuning no matter what way you look at it.
Here's a snippet of the fuel map attached.
From my experience that is fine and would never cause this to happen on this particular setup timing wise vs boost pressure. What caused this to happen is the car was forced more fuel the higher RPM it went even though it was on a MBC and the boost was falling off.
33psi at 7500RPM
27psi at 7800RPM
26psi at 8000RPM
It ran out of injectors and the tuner kept forcing it more fuel via adding more fuel at higher RPM. That is the first sign of a fueling issue, when you have to add more fuel at higher RPM vs take it away even with the boost dropping.
Not to mention as the fuel was being added the AFR didn't move but the IDC kept increasing. It is still irresponsible tuning no matter what way you look at it.
Here's a snippet of the fuel map attached.
Tune a very high HP 2.4 that will tell you who knows what their doing and who doesn't. If you can keep a 2.4 HG together you can keep anything together 4g63 related.
These threads scare me. I had a serious case of contaminated fuel in my new build recently where the fuel tank looked like a sewage drain and i was not ever gonna pull injectors to check them because i am lazy when it comes to my personal car. I think im gonna check them now this weekend after seeing two threads similar that are fuel related damage.
The term for this damage is "preignition" which is different than"knock". Knock is when the spark plug ignites the mixture and it explodes in an uncontrolled fashion. That is bad because it creates high cylinder pressures. Usually this doesn't happen with e85. What does happen with E85 when it is lean is that the mixture ignites on its own during the compression stroke. You now have 2 opposite forces pushing against each other. The other cylinder is pushing the crank forward and the preignition is trying to turn the motor backwards. This is very bad and will destroy everything in short order. This is why I run E85 super fat. It is impossible to foul plugs with E85 and it will help prevent preignition.
Agreed.
Reality is what you can get away with though and I know a 10.5:1 to 11.5:1 motor is picky at 40+psi and low backpressure.
Backpressure on a Black at that level, the 10.5:1 compression, and running lean all hurt it. It was dropping pressure across the board and should have smoked all the cylinders more or less the same. If one injector started the issue or the distribution in the manifold is a problem the 4v knock spikes should have been the key here. First course of action should have been to drop timing.
I did a 10.5:1 Super 99 car in KC last weekend, 14*/8500 at 42psi and saw stuff on the plug chop as well as a semi consistent 3.5v spike. Switched to 9s and the plugs were clean as well as the voltage was down to 2v in the same spot.
Reality is what you can get away with though and I know a 10.5:1 to 11.5:1 motor is picky at 40+psi and low backpressure.
Backpressure on a Black at that level, the 10.5:1 compression, and running lean all hurt it. It was dropping pressure across the board and should have smoked all the cylinders more or less the same. If one injector started the issue or the distribution in the manifold is a problem the 4v knock spikes should have been the key here. First course of action should have been to drop timing.
I did a 10.5:1 Super 99 car in KC last weekend, 14*/8500 at 42psi and saw stuff on the plug chop as well as a semi consistent 3.5v spike. Switched to 9s and the plugs were clean as well as the voltage was down to 2v in the same spot.
Ya I don't run a lot of timing in big turbo setups at all. I usually leave power on the table. I'm still on a non cdi sparktech that's 4 years old on my car and my volts are around 1.5-2.5. I use 8eix plugs. I never thought of going to 9's. i might have to look into that as i up my boost (only 32psi atm). 
plugs were 350z 1 step colder coppers ( LFR6A-11) gapped to .017. literally just put them before the pull it let go
Reason I ran the plugs was via this thread
https://www.evolutionm.net/forums/ev...tml?styleid=23
Others have ran these plugs w/out issue. I've got ikh24s in it now
https://www.evolutionm.net/forums/ev...tml?styleid=23
Others have ran these plugs w/out issue. I've got ikh24s in it now
The IKH24 is the right range, that other thread is an abortion of myth. Heat range 6 dont work in pretty much any universe at anything over STI power levels (stock with a heat range 6 plug).
I haven't read the whole thread so take this with a million grains of salt. I'm just sharing an experience and nothing in this post is pointing fingers at anything.
We had a failure like this on a Time Attack Evo about 6 years ago. FPred, low boost (23psi), 100oct. The driver didn't pay attention to the gauges in the car *le sigh*, ran the car SUPER hot for at least a lap until the steam streaming out of the hood finally got his attention.
Once in the pits, while the guys where pulling the head I was looking over the logs. Zero knock but the temp showed steady for two laps then shot up like a rocket for a lap then the above. Knock filters where stock. Motor was stock minus head milling because the head was off to put a fresh HG in "just in case". Oh the irony....
Once we got the head off, the piston tops looked perfect, even steam cleaned a bit because of the steam room for a lap. However the head gasket was melted and the head was melted worse then ANYTHING I have ever seen. Look like 10x worse than the photo posted in this thread. I cannot even imagine the temps that thing saw. Was just junk at that point.
We figured the head lifted for some reason other than detonation, probably bad milling or head studs stretching.
The good news from this experience is I found out that three guys that know 4G63's well can get a head off in less than 1 hour if they really apply themselves.
Was this car:
Dead head:
Good luck OP.
We had a failure like this on a Time Attack Evo about 6 years ago. FPred, low boost (23psi), 100oct. The driver didn't pay attention to the gauges in the car *le sigh*, ran the car SUPER hot for at least a lap until the steam streaming out of the hood finally got his attention.
Once in the pits, while the guys where pulling the head I was looking over the logs. Zero knock but the temp showed steady for two laps then shot up like a rocket for a lap then the above. Knock filters where stock. Motor was stock minus head milling because the head was off to put a fresh HG in "just in case". Oh the irony....
Once we got the head off, the piston tops looked perfect, even steam cleaned a bit because of the steam room for a lap. However the head gasket was melted and the head was melted worse then ANYTHING I have ever seen. Look like 10x worse than the photo posted in this thread. I cannot even imagine the temps that thing saw. Was just junk at that point.
We figured the head lifted for some reason other than detonation, probably bad milling or head studs stretching.
The good news from this experience is I found out that three guys that know 4G63's well can get a head off in less than 1 hour if they really apply themselves.
Was this car:
Dead head:
Good luck OP.
Last edited by razorlab; May 23, 2014 at 06:36 PM.
so Aaron whats the best plugs to use in a hi boosted 800whp evo 9?
Last edited by bbyevo8u; May 24, 2014 at 05:24 AM.
