Cracked 4th piston AGAIN!!!

[dhump]

Hey Guys,

I think i've cracked the number 4 piston (prob around the 2nd & 3rd ring land) and I was wondering if there is anyway to change the piston without pulling the entire motor out eg. being able to take off the sump while its still in the car??

Also, this is the second time no. 4 has gone on a relatively new motor. Have any of you guys had probs with the no. 4 cylinder leaning out etc. with the L300 intake manifold??

The pistons are hyperutechnic and obivously dont like seeing 16psi!!! Motor isnt even 15000kms old and this cylinder has gone twice with no evidence of detonation....

[Starion_Turbo]

hmm, sounds like forged piston time.

[Starion VR4]

Yea look we had the same problem using those pistons, It seams they don't like ANY DETONATION at all, but for $250 what can U expect, also what ECU do u have? If STD ECU it sounds like yr knock sensor is U/S. If U have an aftermarket ECU then trim #3&4 cly or run 1-2% richer. :beer

[redzone]

Hey Guys,

I think i've cracked the number 4 piston (prob around the 2nd & 3rd ring land) and I was wondering if there is anyway to change the piston without pulling the entire motor out eg. being able to take off the sump while its still in the car??

Also, this is the second time no. 4 has gone on a relatively new motor. Have any of you guys had probs with the no. 4 cylinder leaning out etc. with the L300 intake manifold??

The pistons are hyperutechnic and obivously dont like seeing 16psi!!! Motor isnt even 15000kms old and this cylinder has gone twice with no evidence of detonation....

it must have leaned out or detonated inaudibly!

yes u can jack the engine up off its mounts and pull the sump out without pulling the whole engine out

are u using the stock starion pattern pistons? (heart shape valve reliefs in crown) if so then thats your problem right there. they are a SHIT design, using thin lands and thick rings, with crappy ring spacing to boot. they are basically made of glass and it doesnt take much to destroy them AT ALL!

if u dont wanna buy forgies but want something that can handle 20 psi without cracking easily, then get yourself a set of HYPATEC brand pistons to suit GALANT VR4 turbo same as what i used in my car until recently.

PM me if u want a set mate.