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They call me the destroyer of piston #4 (Rebuild time)


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A new tune was used for the new parts yes. I dont think itd run to good if tuned for an oem ebc and a 3 port ebc was thrown on. I dont recall any random misfires. I remember logging injector duty cycle a while ago on my accessport and i think it was something like 94%. Now if thats the case a tired fuel injector or pump could definently be the culprit. Althrough i think all my spark plugs looked good and healthy (same ones from the old block probably have 20k miles on then.
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all data should have that info. what I'm saying is, most injector failures result in misfires. what is certain is your piston(s) were destroyed from knock events, no doubt about it. if your fuel pump was failing and wasn't providing enough pressure to keep up with boost, you'd knock. if you're saying, ever since you put that new block in you havent had much, if any knock, i'd be very suspect of the tune. because clearly there was knock and it wasn't picked up. what does peak my curiosity is the fact that you were frequently dropping to 0 wgdc, which means your IAM was less than .65, which means you had a lot of knock. This means the ecu was using rough correction to combat knock...it's not a bad thing, and saves the motor, but also means you were knocking a lot, for whatever reason. running an ebcs with a tune made for a stock bcs is a very bad idea. to be 100% honest with you, 25psi even for a second can cause literally, 8+ knock events and a lean spot on the piston and blow the ****** apart, ask me how i know. this is why it is imperative that boost limit table is set appropriately and the map sensor hose does not blow off. overboost is no joke.

 

let's be real here. you knocked enough to destroy that piston and 2 pistons in your previous engine, especially since the middle ring is gone and not the crown. think about what can cause knock to begin with- 1. bad gas 2. bad fuel pump 3. overly aggressive tune 4. heatsoak 5. overboost 6. oil

 

did you log enough? did you have knock? we probably should be asked this at first, looking at the health leading up to failure....

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Ya the logs where you see 0 wgdc is when the piston was actually broken. The only logs i really have saved for when the car was running health was some 3rd gear pulls. Ive never seen boost above 19psi during a pull or at the drag strip.

 

Id rule out heatsoak and overboost. As well as oil. From what i know infamous isnt an overly aggressive tuner.

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I just took a closer look at all the cylinder walls and they look pretty good. Ill post pics of them tomarrow. If the cylinder walls are good i can just drop in some forged pistons correct?

 

 

you can, but i wouldn't. If i was building a motor i would at least go to the next available size. This way all the pistons and bores are in spec and you will know for sure it was done right. just my opinion, i know guys that just honed the cylinder walls and got by with it. But why cheap out? its what $200 to have all the cylinders bored?

The price for pistons aren't going to change much (if any)

best of luck to you hope all goes well!

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I just took a closer look at all the cylinder walls and they look pretty good. Ill post pics of them tomarrow. If the cylinder walls are good i can just drop in some forged pistons correct?

 

The machine shop will tell you that. They will inpsect the cylinder walls and tell you what they find. They will then tell yoou what size pistons you need. When the pistons come in they will measure them and hone or bore each cylinder to match the pistons Dia.

 

All the pistons are not the same size.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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just a thought ripemeat and max chime in..

When I had a bug-eye they recommended replacing the fuel rails for cyl#4 leaning out under heavy boost, Im sure you all know what gets changed in the aftermarket rails, but it sounds like a fuel or tuning problem, and sounds like he has voted out the tune. So if thats the case and its been cyl #4 all along, would the rails be a good investment?

Cleaning and flow testing injectors is liek $25ea through dw http://www.deatschwerks.com/services/fuel-injector-services

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Never ran it hard unless the car was warmed up stayed under 3000 when it was cold. The cross hatching in the cylinder walls look beautiful. I mean it only has 6000 miles on it but i understand exactly what you mean by letting the machine shop measure and do the bore to get the cleanaces perfect. So that is indeed the smartest route.
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Started to order some parts. Waiting on snagging the pistons till I get my block out for the machine shop to look at it.

 

Should I replace the oil pump with a oem one? sti 11mm one? Or leave it? Also should I replace the oil cooler? Just looking for some second opinions on these two.

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just a thought ripemeat and max chime in..

When I had a bug-eye they recommended replacing the fuel rails for cyl#4 leaning out under heavy boost, Im sure you all know what gets changed in the aftermarket rails, but it sounds like a fuel or tuning problem, and sounds like he has voted out the tune. So if thats the case and its been cyl #4 all along, would the rails be a good investment?

Cleaning and flow testing injectors is liek $25ea through dw http://www.deatschwerks.com/services/fuel-injector-services

 

No one on here talks about different fuel rails. If your making huge HP you would need the extra fuel capacity, but at our hp levels, I think you should be fine with OEM rails.

 

I'm sure your Tuner would say the same.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Started to order some parts. Waiting on snagging the pistons till I get my block out for the machine shop to look at it.

 

Should I replace the oil pump with a oem one? sti 11mm one? Or leave it? Also should I replace the oil cooler? Just looking for some second opinions on these two.

 

I told Mike at AZPinstalls to send me what he thought I should use for a oil pump, to be honest with you I don't remember which one he sent me.

 

If you think you have metal floating in the oil from a turbo blowing or bearing damage, replace the oil cooler. I just rinsed mine out with Acetone and blow it dry and let it sit for a few weeks .

 

I think the stock HG will fit a over bore. Again, Mike at AZP would know for sure or m sprank.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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