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looks like I voted in the "built engine failure" too early. althou this looks to be tune or fuel or something? only just click over 10k, recent tune to 700awhp HKS 2.8L CP pistons, TO4Z

long story short, noticed engine using oil, even after changing to a thinker oil,

#6 plug oily , #1 white ?? got compression and leakdown tests

compression (psi) 135, 135, 130, 130, 135, 130

Leakdown (%) 8, 6, 5, 5, 6, 10,

also had a look with the scope, can see #6 has some pitting damage from pinging? (detonation? ) the other pistons look ok ( from the top), so looks like at least 1 new piston. not sure whats going on with #1 ? in the leakdown.

anyway this was supposed to be a short story. If I was to pull the motor out, take the head off etc and just drop off the bottom end, to be stripped and rebuilt with new pistons ( lets just say we go for 6 new pistons, not sure what else would need replacing? bearings etc? ) the main Question from all this is, what is a reasonable price to pay for this job ??? assuming everything else is still serviceable .

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Totally depends on what else you find when it gets pulled apart.

There might be a bit more than just piston dmg due to the detonation.

It could be 2.5k, it could be 4k

yeah i know, can't really say until it comes apart, just chasing ball parks, got a bit of a shock when the first price I got for the above job was $6500+ and that was if they didn't find anything else, ( thats a perth price )

looks like I voted in the "built engine failure" too early. althou this looks to be tune or fuel or something? only just click over 10k, recent tune to 700awhp HKS 2.8L CP pistons, TO4Z

long story short, noticed engine using oil, even after changing to a thinker oil,

#6 plug oily , #1 white ?? got compression and leakdown tests

compression (psi) 135, 135, 130, 130, 135, 130

Leakdown (%) 8, 6, 5, 5, 6, 10,

also had a look with the scope, can see #6 has some pitting damage from pinging? (detonation? ) the other pistons look ok ( from the top), so looks like at least 1 new piston. not sure whats going on with #1 ? in the leakdown.

anyway this was supposed to be a short story. If I was to pull the motor out, take the head off etc and just drop off the bottom end, to be stripped and rebuilt with new pistons ( lets just say we go for 6 new pistons, not sure what else would need replacing? bearings etc? ) the main Question from all this is, what is a reasonable price to pay for this job ??? assuming everything else is still serviceable .

You want to do bearings as well if you are pulling the pistons out due to detonation damage, no doubt they will be roughed up slightly as well.

Also if you can pull the motor out yourself and disassemble it as needed, get someone who knows what they are doing to diagnose the failures/damaged bits then buy the parts yourself and just pay a builder to put it back together you will save a fair bit.

Edited by Rolls

You want to do bearings as well if you are pulling the pistons out due to detonation damage, no doubt they will be roughed up slightly as well.

Also if you can pull the motor out yourself and disassemble it as needed, get someone who knows what they are doing to diagnose the failures/damaged bits then buy the parts yourself and just pay a builder to put it back together you will save a fair bit.

cheers, thats what I'll probably end up doing, try and save some cash and maybe learn a thing or two along the way..

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