Bad gaz? Or low factor of security?

[WorkInProgressK]

A picture is worth a thousand words...

I filled up my gaz at a different station this time. Same octane rating. I have been running my setup for 1 year on the track.

This really pisses me off. I hope the ceramic made its way to the exaust without damaging anything.

Any inputs?

Setup BCPR6E's -> they will be replaced with BKR7E's They look the same. I just know the 7's are a colder rating.
AFR->12.0-12.5 at high revs.
0.9 bar, 370 injectors, 255 walbro fuel pump, GT2871R
I downtuned my high RPM ignition by one or two degree's. (6000-6800)

[Black R]

Wow, idk but I never use anything hotter than 7's even on my allmotor car...

[Def]

Definitely need 7 heat range plugs on that setup. How do the piston tops look?

[WorkInProgressK]

I didnt check... should I?

[Robertftw]

Yes you need to check that, leak down test that cylinder to check for damage to the valves, and check the back wheel of the turbo. Are those injectors big enough?

[WorkInProgressK]

I mean, even if there is engine damage. What can I do about it. I would have to replace it. It is my DD after all, I need to drive it.

I am scared for the turbo doh... If that thing is unbalanced...

Injector are just enough. Just just just. Putting my 600cc in soon I guess...

[Def]

Well, you might see nothing on the top of that pistons, or you might see heavy detonation damage(lots of little pits, mostly in the quench area of the pistons). This will give you an idea of what's up with your setup.

Your plugs don't look too lean from what I can see, maybe running a bit hot due to the 6 heat range, but usually in a lean condition there is much more white on the electrode, and it sometimes looks almost "chalky" from basically cooked off carbon.

[WorkInProgressK]

So there was detonation... Possible cause?

[Black R]

I'm far from an expert, but detonation as I know it comes from too lean or too hot causing the explosion to start too soon. Timing too far advanced could do it too if you're borderline. And of course too low an octane rating.

Did you gap those plugs yourself?

I'd say start with a 7 and maybe try another gas station.

Were you hearing any detonation?

It sounds like marbles dropping on the valve cover.

[Matt93SE]

Can you get a REALLY close up shot of the end of the plugs?

Some info for you that might be of use..

http://www.aa1car.com/library/reading_spark_plugs.jpg

http://www.v6z24.com/gallery/service/repair/Spark+Plug+Reading.jpg.html

http://www.youtube.com/watch?v=fiMM2S0aADM

[WorkInProgressK]

I'm far from an expert, but detonation as I know it comes from too lean or too hot causing the explosion to start too soon. Timing too far advanced could do it too if you're borderline. And of course too low an octane rating.

Did you gap those plugs yourself?

I'd say start with a 7 and maybe try another gas station.

Were you hearing any detonation?

It sounds like marbles dropping on the valve cover.

Like i said earlier, my setup never changed in two years. Pretty much since I changed my turbo. The only differences were installing the nistune board with the same tune that was on my daughterboard, which I was running before and the gaz station.

Nope. plug and play at 0.9 mm.

Actually I recall some rattling sound at high RPM's 7000K+, coming out of the hairpin on second gear. I will be listening next time to see if it makes the same noise with the 7's.

Can you get a REALLY close up shot of the end of the plugs?

Plug chop! (Moped tunning lol) From the looks of it, there isn't much carbon deposit(brown, grey) so I would believe its actually running too hot.



I really suck at taking pictures... Thats the best I can do with the macro mode of my camera.

[Matt93SE]

IMO here.....

The intact plug is too hot. notice how many threads are discolored? that means there's a TON of heat in there and the end of the plug is fawking hot.

The dead plug is.. well. dead.. run a plug too hot and it turns into a glow plug instead of a spark plug, which can cause detonation.

With luck you didn't grind any of that stuff up the turbo. I'm going to guess the metal was burned away relatively slowly and you didn't send a chunk of steel through the engine, but the ceramic is what worries me hitting turbine wheels and doing damage there.

I'd also definitely take a look at the top of the piston and see what you can find.

How's the ceramic that's left on the dead plug? does it have "ash" or any spots on it? Is the ceramic bright white, or dull grey/brown?
If it's got shiny spots on it, that's the aluminum fromt he engine melting and depositing on the plug. not good.

My unofficial opinion thinks you're running a bit too close to the edge on plug temps and maybe timing and AFR. If getting a tank of "marginal" gas puts you over the limit on tuning, then I'd back it off a hair. that engine is just too $$$ to rely on the consistency of pump gas. I can't tell you how many times I've watched the delivery drivers dump the wrong stuff into a tank at a station, or the pumps are labelled wrong.
...In the last 10 years, I've cleaned diesel out of 3 cars, and all of them filled up with regular gas and had the receipt to prove it. the delivery guy pumped diesel on top of the 87 octane tank at the station and the guys never shut it down. "Ohhh, it'll be allright"

(what really irks me are the single-hose pumps we have here that hold at least a gallon of gas.. I paid for 93 octane, and I first have to pump a gallon of 87 before the 93 even starts coming out the hose!)

[WorkInProgressK]

The ceramic on the broken off side is bright white, with some spots of black. On the sides its brownish, more white then brown.

Any idea how I can look on the top of the piston. Its the fourth one. I will try with a flash light. But my car isn't smoking oil.

I will try to crank it to TDC and look with a flashlight...I wish I had one of those optical camera's ATM.

Actually I am 5 degree's lower then stock tune in the high load/high rev area...-_- So you are right, probably with the gaz, it turned into a glow plug .... lol


Update: I saw probably 50% of the piston and there is no sign of damage. I compared it with another cylinder. The piston is covered with carbon deposits.

[CodyAce]

9/10 it gets mashed up in the quench areas and just spits dust out the turbo. Sure those little specs are like taking a jackhammer to the turbine wheel, but shouldn't be to bad. You'd be surprised how resilient engines and turbos are to broken plug parts

[Epstein]

I saw everything I needed to know in the first post. 370cc injectors vs gt2871r on 0.9bar. Even on a bone stock SR20 with low timing, that's more than 370cc will cover. Your injectors are static without a doubt, and even if the wideband says 12.0-12.5 up top, that's the average of all 4 cylinders. A slightly dirty injector on #4 and it could be a lot leaner than that. Dialing back the timing isn't going to do anything if you're way lean.