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Thread: Look what I found? "( (pics heavy)

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Posts: 1-10 of 17
2011-11-16 23:38:26
#1
Look what I found? "( (pics heavy)
long story short I took the DET out the Daily B13 and put the built VE-T in for break-in, The det would smoke when accelerating hard so I thought maybe a piston ring/ring land?
I took the DET apart today and this is what I found....Yup all 4




Block is done too...



I know it could of been number of a things but the main culprit?

this is what the bottom of head looked like..


whta you guys think?
2011-11-16 23:47:18
#2
Are any of the lands between the top and 2nd ring broken or cracked. If not you probably wernt smoking because of that damage unless the walls are scored from material from the piston going onto the cylinder wall or bent rings from the hard detonation. If you have no cracked lands then im surprised it took that much detonation and didnt crack the ring lands. Ive had way less damage on the pistons and had the ring lands crack. But i guess it depends on just how hard the detonation is.

I see it started to push your headgasket firing ring out in that one spot, im surprised you werent getting coolant into the cylinder or pressurizing the cooling system. It looks like it was on the verge of breaking if it hadnt already.

Yeah the block is probably unusable. I had one resurfaced that had minor pitting on the deck but thats pretty bad and deep. Not likely to get rid of that from resurfacing.
2011-11-17 00:35:04
#3
no lands broken..I was surprised also
2011-11-17 00:41:07
#4
looks like some serious detonation, maybe even something built up and caused a serious hot spot there as well
2011-11-17 01:25:49
#5
is this a tuning issue? my AFR looked good through out the whole power band never leaned it out....???
2011-11-17 01:37:57
#6
Depends, what were you running for boost on it?

It could be too much timing but usually see that from too much boost on a T2 frame turbo causing hotspots on the pistons and then eventually detonation and deterioration of the piston, block, and head

Backing down the timing will only do soo much when overboosting a t2 turbo but hotspots are still gonna form because of the excess backpressure.

Again need more info on what you were running.
2011-11-17 01:40:25
#7
I went through de after de with my t2 setup because i was overboosting it. It didnt like any more than 13 lbs or so from the t25 before problems would arrise and eventually destroy the pistons. I was also running jwt s4 cams. I mean even at 9 lbs of boost the thing was fast as hell but yeah just started to push it past its efficiency range.

I had my a/f in the 11.2-11.5:1 range and it didnt matter, also had my timing backed down several degrees throughout the map and still had problems with detonation and hotspots on the pistons when going over 13 lbs of boost.
2011-11-17 01:57:22
#8
Originally Posted by ashtonsser
Depends, what were you running for boost on it?

It could be too much timing but usually see that from too much boost on a T2 frame turbo causing hotspots on the pistons and then eventually detonation and deterioration of the piston, block, and head

Backing down the timing will only do soo much when overboosting a t2 turbo but hotspots are still gonna form because of the excess backpressure.

Again need more info on what you were running.


my setup is in my sig the 94 ser
daily i would run 10-12psi and hardly ever go into boost on
thursdays @ the track 16-18 psi
it did start to give me over heating probs and I couldnt find it but it was blowing the coolant into the reservoir and over filling some times

do all det's come with 54c pistons or only gtir's?
Last edited by klassickrican on 2011-11-17 at 02-03-26.
2011-11-17 02:21:15
#9
Shouldnt have had a problem with the 10-12 lbs daily, if you did the 16-18 on pump gas thats probably why you were detonating. You needed to be using a higher octane fuel for sure. At least 100 octane.

Thats the reason you were having overheating problems was because your headgasket was blown.

If your using that same turbo on your ve, the ve is a little less septable to detonation but still, you might want to get your a/f ratio into the lower 11's in boost to be safe and might want to take out some timing at the peak torque range as well. Definitely be careful until you get it fine tuned in. You would have heard that much detonation as well. Should have sounded like rocks in a can
2011-11-17 02:55:33
#10
Looks like a lean condition.
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