Anyone have a beater car I can drive for maybe a week or 2?

Chuck Branscomb · **Posted:** Tue Feb 22, 2011 10:11 am

JamesShort wrote:

Chuck Branscomb wrote:

Wow, I'm not an engine tuner by far, but if that plot is from WOT through the whole rpm range, that looks nasty. Imagine a 5th (or 6th? if the car has it) long pull up a steep mountain highway with a fully loaded car. Seems like a dangerous factory "design" plan?

Yep, that's why downshift into 4th at highway speeds to pass to get into the 11.xx:1 range above 4k rpms.

...but as a car company, how in hell could they take the risk of an A/F like that with a boosted engine? It looks like one of those "it's only a matter of time" type of things that will come back to haunt every engineering manager and bean counter that approved the release of the product.

JamesShort · **Posted:** Tue Feb 22, 2011 10:15 am

Yep, I'm not trying to justify Subaru

.

One thing that a dyno plot doesn't tell you is how the engine/ecu adjusts for varying conditions.

Being on a dyno in 4th gear with a big fan blowing on the radiator doesn't take in account the weight of the car, or going up a grade, or aero drag etc, so while a 4th gear pull might be a highER load condition than 1st gear, the ECU might be smart enough to adjust for true real world high load conditions but who knows.

JamesFeinberg · **Posted:** Tue Feb 22, 2011 10:23 am

I've spent my fair share of time around turbo engines and all I can say is WOW. That graph is absolutely horrendous. James, that's actually much worse than I was expecting when you described it to me.

I'd be surprised if the real-world AFR's are much better just based on my own experiments and observations over the years. I don't know what dyno he used but, in general, they tend to generate a lot of load compared to the real world at low speeds. If anything, I'd expect the computer to dynamically adjust the AFR's even higher with less load. Scary!

Jim

Les Davis · **Joined:** Fri Aug 29, 2003 2:04 pm **Posts:** 2059

Yeah, I second the comments, that just looks simply outrageous to be that lean during the onset of boost.

JamesShort · **Posted:** Tue Feb 22, 2011 12:53 pm

Les Davis wrote:

Yeah, I second the comments, that just looks simply outrageous to be that lean during the onset of boost.

It's not even the 'onset' of boost. I might be at 6-8 psi by 3500 rpms

.

BUT there are tons and tons of other WRXes out there that are not nearly as well maintained and cared for that are driven hard day in and day out who have much more miles than mine and they aren't blowing up. I let the coolant get to 180degF+ before I go over 3000 rpms. Let it idle in the grid to cool the turbo etc off. Only run Shell 93. I drive like a grandma around town.

I think the manufacturing process of Subaru cast pistons is just hit or miss (mostly hit) because I really don't think they are all popping

Michael Westerfield · **Posted:** Tue Feb 22, 2011 12:57 pm

If the data is available, has anyone ever compared the AFR of stock tunes from WRX/STIs from various different years?

JamesShort · **Posted:** Tue Feb 22, 2011 2:11 pm

I found a few 06 and 08. The shape of the AFR curve and where it switches over to rich is VERY similar. But the actual numbers are skewed towards the rich side (ie good) makes me wonder if that guys data collection was not calibrated/corrected. The 08 was leanest at 13.xx:1 which is richer than stoichiometric.

I somehow doubt my car was running at 15:1.

JamesShort · **Posted:** Wed Feb 23, 2011 12:59 pm

Compression test was fine they said. Seems that compression test is usually good enough to identify bad ringlands but I think they should do a leak down. So that might be somewhat good news. Maybe it is just the turbo.

Steven Carter · **Posted:** Wed Feb 23, 2011 2:13 pm

well that's good news. Very glad the compression test was normal. Would be good to confirm with leakdown, just for peace of mind. James I know you don't have a boost gauge on yours, so I did some rough measurements this morning. The car generates up to ~8 psi on WOT in first gear prior to 6k, is under 5psi in the "lean range." In second gear, peak boost is reached above 4500 at about 15psi, then boost control drops it to 13.5 or so until 6500. In third gear at 2500rpm boost builds more slowly, but peak boost occurs sooner, towards the 4k range, and hits near 10psi just under 4k. So, even though it's leaner at lower rpms, the boost is not near peak--maybe that compensates for the AFR? {shrugs} I'm no tuner guru though.

Aaron Buckley · **Posted:** Wed Feb 23, 2011 5:15 pm

JamesShort wrote:

Compression test was fine they said. Seems that compression test is usually good enough to identify bad ringlands but I think they should do a leak down. So that might be somewhat good news. Maybe it is just the turbo.

I got your message after the meeting I just got out of. Yes, it's kind of what I expected, which is good. I am betting there is something going on with that PCV replacement that is causing one of the oil seals on the turbo to leak due to pressure at idle.

Generally, bad ring lands seems to cause more smoke at the top of the rev range. It sounds positive. - AB

JamesShort · **Posted:** Wed Feb 23, 2011 5:21 pm

I was talking to James Wilson. He did some sort of STI vs EVO thing on a speed tv show (airs in a few months) in a 2011 STI. Apparently they had a similar hthing happen to them (smoke at launch and idle but not on boost). However, they did not have oil leaking out of the engine or smoke out of the oil filler tube.

I'm asking him to get me some contact info for who owns that car to see what happened.

I just got off the phone again with Folgers. They checked the PCV system and said it's fine and that there is a lot of oil in the intake/intercooler. They are cleaning it up and seeing where it is leaking and then running the car to see where it originates. I think it is just crankcase pressure pushing oil out of the cam and crank seals as well as the PCV system (which are just vacuum hoses with crappy spring clamps on them so a lot positive pressure on that system will probably push oil out.

JamesShort · **Posted:** Thu Feb 24, 2011 5:16 pm

Well apparently there is nothing wrong with my car

. I'm a loss for words....which some of you may know is not easy.

Compression test results

1 134
2 136
3 135
4 137

Subaru says 142-170 is normal. So they are all consistent, but all skewed below the normal range.

Well I guess my wife and I can drive to Charlotte this weekend and pick it up. First thing is the konis, FSB and exhaust are coming off and the OE bits are going on. Getting PDR on the small dent on the quarter panel. Put the non cracked bumper on, clean her and off to be sold.

Chuck Branscomb · **Posted:** Thu Feb 24, 2011 6:19 pm

...to be replaced with?

Kevin Allen · **Joined:** Thu Aug 28, 2003 6:42 pm **Posts:** 3479

You should get an 05-06 STi and give Liz some STU competition.

Or a Mustang.

JamesShort · **Posted:** Thu Feb 24, 2011 6:44 pm

08-11 Civic SI Sedan.

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Anyone have a beater car I can drive for maybe a week or 2?

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