ROFLMFAO

Steve was far too polite. My reaction on reading Chris post was.... Foxtrot Foxtrot Sierra.... not again....can't he build a donk that doesn't auto-destruct

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

It's all good fun.

Is this the original forged engine that was a lottery purchase? (Ie it's condition wasn't known).

The IGT/IGF thing is interesting. I had no idea there was any sort of feedback that tells the ecu the spark plug had operated.

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GT4DC Events Co-ordinator
1996 ST205 UK

All the ringland failures were in the same engine.
the forged engine was an Ian smith one with a cracked block re housed into robs old block which had been bored 0.1mm too big, so a bit smokey which didn't bother me for low mileage & competition.

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If at first you don't suck seed, try drier grain.

Hi,

i doesn't read the whole thread, but rinland failures occure like this

threre are two different type of ringland failures like on the picture, Abb.4 show a failure due to a wrong installation of the piston (wrong tool), the force comes from the buttom

and Abb.3 show us the ringland failure we often have on our pistons, most people think that this is becouse our pistons are bad, it is simple a material overloading
the following reasons occure this

- to low octan,
#1 the uses fuel is not able to anti-detonate the engine on all active workings
#2 oil enters the combustions chamber which lowers the octan
#3 wronng ignition timing
#4 to lean running engine (but i think not on a 3S-GTE which runs very rich)

- liquid beat, fuel, oil or water enters the running or stoped engine, liquids are not compress able
#1 water enters the engine threwe the intake system
#2 water enters the engine becouse of damaged parts like head gasket or intercooler
#3 fuel enters the stoped engine becouse of a damaged fuel injector



greetz

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KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

Interesting post Sunny, thanks.
Just checked my box of broken pistons and it seems it wasn't my bad installaton. Whew

Still not 100% certain of the cause, I suspect maybe a combination of several.
Too large piston to bore clearance allowing more blow-by so running hotter. Also less suppression of shock waves. (No. 3 particularly was a bit of an old slapper after several hones)
Intermittant fuel loss causing weak mixture ? - injector, fuel pump, cavitation / air bubbles in fuel.
Intermittant ignition over-advance due to overheating igniter ? (prime candidate I think now)
Bad mapping ?

I'm hoping to get it running in the next couple of months so I can study further. Was going to be over Christmas but a bad back made me do the ECU design instead.

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If at first you don't suck seed, try drier grain.

Just a note, the melted piston could well have happened after the initial failure of the ringland if you kept driving on it.

No-load rev-limit action is where pistons and rods die, it's the worst case load scenario.