Detonation Damage.

[Busky2k]

My mate with a R34 GT-T noticed some severe misfiring after giving his car some stick on a hot day. We pulled the sparkies and I almost had a heart attack... and this is how 5 of the 6 looked.

Changed em and the car runs fine now. Its a miracle the porcelain/metallic bits didnt seem to damage the ceramic turbine or valves. Then again I haven't done a compression test since. Is this guy lucky or what!! No I didn't create this thread to bag out my mate, just to show you guys what kind of damage detonation can do and how easy it is to loose a motor.

[Craved]

what plugs are they ???

[Busky2k]

NGK Platinums. lol

[carl h]

proly a heat range too hot for the area, try a colder plug and reset timing to spec.

[hanyou]

damn haha

[r33_racer]

Hes probably gonna have some nice chips out of the crowns of those pistons, probably off the exhaust side. When the heat gets too high the coatings can come off any of the fancy plugs, especially if you regap them yourself. coppers for the win.

[carl h]

here here!

When the heat gets too high the coatings can come off any of the fancy plugs, especially if you regap them yourself. coppers for the win.

[Adriano]

i doubt that this is caused by detonation, as 5/6 looked like this, i would say the cylinder temps are too high for the plug. if the plugs are too hot it will cause detonation

[RPMGTR]

Superb demonstration of detonation!! Best get it looked at or it will be new engine time very shortly......

[Busky2k]

They were PFR6s. Not exactly a 'hot' plug since the NEO uses a 5 as standard IIRC? Anyways they were replaced with BCPR7ES.

[Bl4cK32]

did u turn the motor over once with each plug out to blow crap that might be left in there out of each bore? A piece of spark plug could cause pre ignition if its inside the camber...

When i pulled apart my old motor it had small bits of crap floating inside, ontop of each piston...

[Adriano]

IMO if this was caused by detonation, it would be very unlikely to have done 5 sparkplugs, as i would have thought detonation would be more prone in one perticular cylinder, then the next. By the time you have 5 cylinders detonating, something would break. Is it possible the fuel pump is on its way out, causing lean mixtures hence far higher combustion temps causing spark plug melting and detonation. Just my 2c, correct me if im wrong

[r33_racer]

I thought he meant only 5 and 6 were detonating, thus the melted and ally covered plugs in the pic. But it could have easily been due to leaning out and its what caused the detonation and high temps.

[Adriano]

5 out of 6:) scary, i think there may be a problem

[T04GTR]

piston pics please

[Beer Baron]

time to take it somewhere with a bore scope I reckon.

[r33_racer]

haha ok..sorry i stand corrected then...5 out of the 6...DAMN...thats bad!

[l0WRB]

im guessing the ends of the plugs would have burnt up long before they reached anywhere near the turbo wheels...?

[MANWHORE]

that metal odesn't burn. my guess would be, it's sitting ontop of the pistons, scratched the bores, everywhere in the oil, in the valves, and just about everywhere short of being in the window washer fluid.