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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. :rant:

sparkiejs4.th.jpg

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.

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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.

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...

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

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