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Posting for a buddy (I'm a dealership Representative)

Username: (WITHHELD)
Car and Year: '13 Focus ST
Mileage: 18,000
What failed - piston, rod, injector etc?: Unetermined - Coolant in number 4.
Modifications and tune: Stage 3 91 OCT Cobb
Under what circumstances did it fail (WOT, cruising, what did you hear and feel?): Driving down road, suddenly no power and limps. Misfiring HARD.
Any signs prior to failure?: Check engines for a few cold days.
Warranty?: TO be determined. He was denied warranty coverage at his dealer, so I made sure there was no record of his visit and Took him to My dealer.

Pics submitted to Tech Support waiting on Approval. Will be covered, car is now bone stock.
Is this the guy with the aftermarket wastegate actuator that they couldn't install correctly?
 
7500$ for pistons yeah that sounds rite :///. No 7500 for everything including pistons and labor and installation of other aftermarket parts. Still tryin to determine root cause for sure but will more than likely upgrade injectors and pump in the future.
They don't exist yet, and have not proven necessary up to 300+ hp

Any more info on these pistons?


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Yes they do they exist there's a walboro 255lph pump out for it now as well as injectors. I will post pictures of pistons when I'm he.
Your Walboro won't help, it's the DI pump that's the issue, if anything...


And no one makes DI injectors yet, besides mount yen and they arnt much of an upgrade


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The in tank "walboro" is not the issue...and the injectors are not proven at this point. they claim 360whp with them and we are making that with the stock fuel..

Might want to read up a bit more before you spend the money......I see your in Michigan....what shop is making the pistons? you should 100% have them coated at Line2Line Coatings They are in Clarkston and the coating will make them break in MUCH better and last forever. you will make sure you're riding on oil and not metal to metal.

you would want the Slick CC baked on:
Piston Skirt Coating reduces operational clearances, protects piston skirts from scuffing, retains oil, and reduces friction. Recommended when piston and bore dimensions are providing stock clearances. Reduces slap and ring flutter compared to uncoated pistons, effectively improving ring seal and reducing wear on the pistons and rings. Also protects the interface from foreign particle wear. During a short break-in cycle (5-15 min), excess coating thickness will wear away where contact stresses are highest. Where there is room, lower contact stresses allow the thickness to remain and reduce operating clearances.

If you call over there, talk to Andy (he is the owner) and tell him PJ sent you his way. They have their stuff on over 1,000,000 OEM superchargers and are a hose hold name is the big HP race engine world...


Let me know what shop is making the pistons though..please

Your Walboro won't help, it's the DI pump that's the issue, if anything...


And no one makes DI injectors yet, besides mount yen and they arnt much of an upgrade


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Discussion starter · #51 ·
View attachment 34987 View attachment 34988 View attachment 34989

2013 silver st
10,000 miles it blew up

After fixing suspension noise and took for a test ride. car was driving fine and all of the sudden misfire on cylinder 4. Inspected it and this is what happened. Car was running on a stage 3 93 oct tune from cobb. Car has cobb FMIC, cobb intake, cobb 3" downpipe, 3" agency power exhaust. Took it to get fixed and wasnt in warranty and ford wanted to charge me 10k for a new engine. NO thanks so i went to a local shop who specializes in turbo cars. He told me cylinder #4 was running to lean and got to hot and gave out. Said there was no way u can run a stage 3 like that without supporting mods a high flow fuel pump and bigger injectors. Made me a one off set of custom forged pistons saved about 2.5k. While it was there had them install my new Quaife LSD and clutch.
Thanks for the pictures. That is definitely a damaged ringland and most like a result of detonation. There's pitting all over the top of that piston.

Did you do any logging on the car to check that the tune was not too aggressive for the fuel you are running?
The car does add more timing when coolant and CAT temperatures are lower.
With colder air temperatures the car will also ingest MORE air at the same boost level and is more prone to spiking/running higher boost. This can exacerbate a detonation issue.

 
wait I thought you said a local shop made them? JE makes GREAT stuff but they are in CA some place I thought?

Where is your car being fixed? Did they just order you pistons? and did you do rods too?

Get those pistons coated.
 
wait I thought you said a local shop made them? JE makes GREAT stuff but they are in CA some place I thought?

Where is your car being fixed? Did they just order you pistons? and did you do rods too?

Get those pistons coated.
Sorry should have been more specific. They were going to be done locally but had problems and guess guy didn't want to do it. He had them sent out and made. I will be seeing the guy this weekend so I will have him do a write up on everything he did so you guys can have more info. Car was being fixed at millenuim auto in Romeo Michigan.
 
Ahh the SUBARU guys. They are a respected shop for sure in that community. They are known for buying wrecked Subaru's, Fixing them and then selling with a rebuilt title.

Get those pistons to Line 2 Line before he puts them in for you......I am guessing your re using the stock rods?
 
Unfortunately I did not log the car to really find out but your right car pretty much had a way more aggressive tune than needed. I'm just curious tho would the quality of 93 octane in Texas be that much different to cause it to run to lean. Because a buddy of mine was gonna have his car tuned down there a they told him to bring his own gas since there 93 is a lot stronger.
 
Ahh the SUBARU guys. They are a respected shop for sure in that community. They are known for buying wrecked Subaru's, Fixing them and then selling with a rebuilt title.

Get those pistons to Line 2 Line before he puts them in for you......I am guessing your re using the stock rods?
I wish I would have known this before they are Already back on the car :(. Yeah hahaha I was the guinea pig first one they've done so was a little nervous at first.
 
Discussion starter · #60 · (Edited)
Unfortunately I did not log the car to really find out but your right car pretty much had a way more aggressive tune than needed. I'm just curious tho would the quality of 93 octane in Texas be that much different to cause it to run to lean. Because a buddy of mine was gonna have his car tuned down there a they told him to bring his own gas since there 93 is a lot stronger.
My experience with Texas 93 is that it is not very good. Again this is vehicle and location specific however.
 
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