420 / 445 , 2011 sti 20gxt Topspeed SS1

[WRXt4cy]

I've already tuned my car E85 with the stock turbo. We're at about 80% E here. I've got my AFRs in the high 11's, a little lower when spooling to help it spool faster.

You're correct that higher E content will lean out your AFRs and lower will richen them up. I set my tune up so that 75% E hits mid 11's, 70% will be low 11's and higher blends push into the high 11's.

Anyway - that really sucks to hear it broke while on E85 but I wonder if it was weak from before? Had your car ever spend any time on the stock tune? I was paranoid about the bad stock tune so I tuned my car right away and kept it on a conservative stage 2 tune for the first 12,000 miles I had it. I've had it on E for 3000 miles now and so far I haven't had any issues with oil consumption or any signs of issues. I'll probably do a compression check soon though just to be sure.

What the was the history of your car before the ringland broke?

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[threelete]

Originally Posted by WRXt4cy

I've already tuned my car E85 with the stock turbo. We're at about 80% E here. I've got my AFRs in the high 11's, a little lower when spooling to help it spool faster.

You're correct that higher E content will lean out your AFRs and lower will richen them up. I set my tune up so that 75% E hits mid 11's, 70% will be low 11's and higher blends push into the high 11's.

Anyway - that really sucks to hear it broke while on E85 but I wonder if it was weak from before? Had your car ever spend any time on the stock tune? I was paranoid about the bad stock tune so I tuned my car right away and kept it on a conservative stage 2 tune for the first 12,000 miles I had it. I've had it on E for 3000 miles now and so far I haven't had any issues with oil consumption or any signs of issues. I'll probably do a compression check soon though just to be sure.

What the was the history of your car before the ringland broke?

For starters I logged this AM on the way to work
@ WOT:
.80 Lambda - Max duty cycle was 92%

History of my car.

1000k- flashed to Cobb Stage 1- 93
1500- added Cobb SF and Flashed Stage 1 SF 93 octane
2200- Added Invidia DP mated to stock catback, Flashed Stg.2
8500K- drove to Cobb Plano. 20gxt7cm, Walbro 255, ID 1000cc, Grimmspeed EBCS, E85 and 93 Tunes. 373/372 on Mustang dyno
13,500k- #4 cracked. Sent car on truck to Topspeed
Got back: Car had 16,000k on it last fall, Topspeed broke it in.
I have 33k now. I'm high mileage driver

SS1 forged CP block installed (new block), Aeromotive FPR, Aeromotive 340 fuel pump (I'll explain), Crawford AOS.
Got the car back with E85 and 93 tunes. there was E85 in the tank when I first drove it and it felt basically the same(386/412) dyno jet.
While my car was getting broken in Topspeed called me and asked it I had noticed a big hesitation between 2500-2900 rpms before the car failed and I told them I had!

Well, the car was still doing it with the new engine.

BEFORE THE PISTON BLEW HERE ARE SOME SYSMPTONS I WAS SEEING: My Walbro had started getting very loud before I had a piston issue on stock block. I sent logs to Cobb and they said it was fine. the walbro was making the start up hum noise longer and sometimes for an entire trip it would hum .Then one day I'm driving on a 98 degree day and not even driving hard and when I stopped the car threw a code? and was shaking. I sent logs to Cobb again and this time they confirmed bad misfire. Local compression check verfied. When I would start the car it was skipping #4, it was obvious at idle. My oil levels were checked weekly and they were OK, very small losses over 1500 miles.

SO, when Topspeed was still seeing the hesitation on the new engine I got worried. they replaced the Walbro with the Aeromotive 340 and also installed an Aeromotive FPR. The problem went away. So, my best guess was that I had a fueling issue. Originally when I left CObb i was told to continue using stock Subaru or Equal Oil. Oil change intervals were not stressed to me so I went with 2000 mile intervals, which Topspeed recommended was borderline too high. I'm going with 1500 mile intervals now and using eneos 0w50 or motul 10w40 when running E85 only. I do 3000 on 93 through the winter and I stick with the good oil. the Crawford AOS is good insurance also. I put the EL headers on also and the increased engine Vol. Eff. probably helps too. Bottom line after reading upon end is that our cars seem to fail selectively. Letting the car warm up in the AM, etc. all helps. When I start it in the AM and it's initially very loud and settles down after about :30 seconds then I sit for a minute before I go. I treat her like one of my kids now.

Another key thing Doug Wilks noticed on the dyno last week was that Fuel Pressure was low at start up. One of my lines on the fuel pump was loose. The toggle on the plastic body of the was slightly bent so the line was slipping. he wired tied it so it can't slip now.

I hope this helps.

Brian

[threelete]

HERE ARE SOME PICTURES OF MY JOURNEY. NOTHING SPECTACULAR (iphone).

http://photobucket.com/threeletesti

[WRXt4cy]

Thank you for posted that detailed write up about your car's history and problems. That does help a lot.

I've seen a few 2011 Cobb AP stage 1/2 STis break ringlands, one as early as 4000 miles. I've logged a couple too and they knocked pretty bad and one leaned out going into boost which is really bad. I don't know if they are just bad tunes or if that's the nature of a off the shelf map vs getting custom tuned. Maybe that weakened up your piston... maybe not.

I'm on a DW65c pump myself. I've heard of too many failures with Wally's, especially on E85 to trust them. My DW pump has been solid so far.

That's interesting that Topspeed recommends early oil change intervals with E85? Do they believe E85 breaks down the oil quickly then I assume? That's a little concerning. I've run Rotella T6 for years in 3 different Subarus and that's what I still run now. I do 3k oil changes and have about that on E85 now so I am about to do an oil change. I might send a sample off to be analyzed and see what they say about it.

I don't believe FFVs tell you to change the oil sooner if you run them on E85 do they? I know there is a big difference between an E85 Subaru and an FFV, but still, you'd think it could still affect them.

[threelete]

Originally Posted by WRXt4cy

Thank you for posted that detailed write up about your car's history and problems. That does help a lot.

I've seen a few 2011 Cobb AP stage 1/2 STis break ringlands, one as early as 4000 miles. I've logged a couple too and they knocked pretty bad and one leaned out going into boost which is really bad. I don't know if they are just bad tunes or if that's the nature of a off the shelf map vs getting custom tuned. Maybe that weakened up your piston... maybe not.

I'm on a DW65c pump myself. I've heard of too many failures with Wally's, especially on E85 to trust them. My DW pump has been solid so far.

That's interesting that Topspeed recommends early oil change intervals with E85? Do they believe E85 breaks down the oil quickly then I assume? That's a little concerning. I've run Rotella T6 for years in 3 different Subarus and that's what I still run now. I do 3k oil changes and have about that on E85 now so I am about to do an oil change. I might send a sample off to be analyzed and see what they say about it.

I don't believe FFVs tell you to change the oil sooner if you run them on E85 do they? I know there is a big difference between an E85 Subaru and an FFV, but still, you'd think it could still affect them.

E85 adds quite a bit of moisture to the oil, but I honestly think it's just good for any shop to say "short oil change interval" to prolong the life of their products (engines) out on the market. After having my motor fail I'll do whatever they say and stick to it! I keep all my records etc. and buy all my oil from Topspeed to keep my records and engine clean sailing. The Rotella T6 is also a product that Topspeed said many of it's customers run and that it is a good product. More frequent changes is less friction so I do it.

Honestly, before I went through all of this I wasn't much of a car person at all. I've learned a lot through all of this and I'm continuing to learn more! You heard anything about a fuel filter that needs to be changed in our cars because of E85 sludge? I saw this on an FFV forum.

[jorge0886]

Is this your daily driver, I'm curious?

[tazswing]

For the fuel pump, did you re-wire the relay to provide more voltage?

[CeeMan36]

Did they swap the exhaust housing/ turbine on the Turbo?

[modifyd]

That car must be fun to drive.