JE piston carnage! lots of pics

[lintlars]

Ok ive been running these pistons for about 6 years first on a upgraded ct now the last summer it was on a gt35r w 680 injectors the amazing thing is all pistons had major damage but a leak down test came out good less than 4%for all cylinders except #3 and the HG remained in place (cometic) even the head has heat damage MY AFR was always rich 10s with the 680s even under WOT can too much fuel cause this type of damage? I was at the track when I started to notice I was getting major blowby I was running 50/50 c16 and 92 octane anyways the first shot is of the damage to the combustion chamber of the head enjoy!
most of the damage is located on the intake side of the pistons


piston #1

piston 2 4 5 6




piston #3 had a 50% leak down these are all shots of that





heres the cylinder wall of #3 and #4

 

[CPT Furious]

HOLY CRAP! DAYUM!

 

[Clip]

damn. that is amazing

 

[lintlars]

Im not sure which way to go now rebuild (new head pistons Im not sure if the block is salvagable my pistons are 83 mm anyone know how much we can bore the block out? Or else 2j maybe

 

[Kai]

I've heard and seen 7M blocks bored to 86mm...

 

[abustiffy]

What are you running for engine managment? 10:1 afr isnt shit when you are running 35# of ignition timing at 20psi.

 

[Reign_Maker]

Man, that's a lot of build up... Yes, running rich, that rich will cause a lot of carbon deposits like that... You change your spark plugs often? How fouled up were they?

And I would say that running them for 6 years, two different turbo set ups, and Im sure on the GT35 you were gettin good power, I would say you did REALLY well... I would be happy as hell to get 6 long solid years of fun out of my set up...

What were they bored over? I wouldnt go more than .050 over, .040 is really the highest I would go, but you can go .050 over... And when you tune again, tune for mid 11's on the AFs...

 

[lintlars]

hahha thats not carbon build up thats missing aluminium Ive never had fouled plugs and the plugs were always brown and my pistons are 83 mm not sure on the cylinder bore 30 thou over I believe

 

[slidebabyslide]

wow man, i have seen some really bad pistons but never like yours, wow they got freaken hot , what kind of plugs were you running?

 

[lintlars]

ngk plugs bcpr7es if I remember correctly, no signs of problems from the plugs engine managment was stock ecu with lexus AFM and a rebic lc for rough fuel adjustment I have an SAFC but it did not get installed timing was at 8 deg. Im looking into individual EGTs per runner so this can be avoided next time Im also using a LM-1 for AF monitoring

heres another pic of the head that shows the missing aluminium

this is from cylinder #3 but all have similar damage

 

[starscream5000]

Holy shit.... For safety's sake when you rebuild, I'd use a different head and block.

 

[tubbie]

A friend of mine had JEs in his supra. After about 7 year with a t66, his pistons melted almost like yours there and a few of the pistons were oval when taken out. No change in tune or anything during that whole time.

hmmm...... must be a JE 7 year life expectancy thingy??

 

[slidebabyslide]

are you going to use JE pistons again or get different ones>?

 

[ViR2]

I've seen similar results with s14 JE's. Thats why wiseco is the best there is

 

[lintlars]

wow never heard about JEs giving up I HAD a ceramic coating on top as well Ya I probably WONT be going with JEs again and yes I have a spare block just need to track down a head to rebuild it was fun while it lasted! but can someone explain why most of the damage is centralized to the intake valve side of the piston.

 

[whenmunkysfly]

I've seen similar results with s14 JE's. Thats why wiseco is the best there is

I have heard/seen worse out of wiseco's. im taking a dime sized hole in the piston. I will never run wiseco's after seeing that. I just rebuilt with JE's i guess we will see how it goes.

 

[abustiffy]

It isnt the pistons. They dont randomly catch on fire, taking the head out with them. It is tune, or lack of. You can be "a little off" and last awhile till something goes wrong. A incorrect mix of gas that is less octane than what you tuned on, knock sensors not acting quickly enough; things of this sort are what kill motors. This process could have started months or years ago. You put that much money into a nice setup, why not go standalone or atleast something like an emanage that will allow you to adjust timing where it matters, not just taking an educated guess, backing off the cps, letting the rest of the map suffer.

 

[irocznissan]

wow good stuff. well a bore would be the best way to go.

 

[lintlars]

Yes a agree standalone would be nice but were talking 3000ish$ it has been done on stock ECU next year I will be using individual EGTs for more acurate readings if I cannot get a proper tune then I will consider Standalone

 

[Tun_x]

ngk plugs bcpr7es if I remember correctly, no signs of problems from the plugs engine managment was stock ecu with lexus AFM and a rebic lc for rough fuel adjustment I have an SAFC but it did not get installed timing was at 8 deg. Im looking into individual EGTs per runner so this can be avoided next time Im also using a LM-1 for AF monitoring

heres another pic of the head that shows the missing aluminium

this is from cylinder #3 but all have similar damage

A standalone would be money better spent than individual egts... the egts do you no good without the ability to tune each cylinder.. they might help find a partial miss ..