someone take a look at these logs please ver 2.1

[Deer Killer]

FYI guys don't freak out that much, KC > 0 is a "good thing". If the KC is not as high as you expect it's because the ECU found the highest safe timing below that. The system works as designed. We just all expect a "safe" tune to allow max KC, it means we're not even close to knock, and have even more timing "headroom" in case something goes wrong *which it does* as the engine ages.

[Deer Killer]

Yeah .. I won't give out any names on who this is, but when my car would go into limp mode (hitting only 9 psi) which seemed to go on a two week cycle, I called the place about it, I didn't talk to the tuner himself but the person I spoke to, told me it was probably due to "heat soak" yeah ... 65 degree's out, heat soak my azz .. that's when I did these data logs and saw this crazy timing being pulled.

Why the hell not? name names. This tuner voodoo stuff is bullshit. Either you understand the science/engineering behind it or you don't. _WE_ need to know who is incompetent so our cars don't blow up.

[Legacy05]

So ... with that first log I posted, your saying its ok??? Or should I stay on the COBB Stage 2 map that I just re-loaded .... heh.

[Legacy05]

Ok ... I took my car to Dynocomp here in AZ ... now, the car seemed to run great for a couple of months then my car started to go into "Limp Mode" ... etc ... I never did contact the Tuner to discuss the bad log and crazy timing that I was getting. So I never gave him a chance to fix the tune, I just didn't have the $$$ to spend more time on the Dyno .. the whole protune itself was not CHEAP.

[rao]

You folks are lucky that the Subaru ECU dynamically manages knock as well as it does or there would be lots of blown motors. It is VERY unusual for the ECU to be able to make the adjustments that all of these "tuners" are relying on.

[Legacy05]

All I want is a safe stage 2 tune damnit!

[rao]

All I want is a safe stage 2 tune damnit!

 

 

Cobb provides several and they are free with the purchase of an AccessPort

[2005garnetGT]

Cobb provides several and they are free with the purchase of an AccessPort

 

+1, cobb has a great canned flash.

 

do you guys really think cobb is artificially limiting their tunes?

[mickeyd2005]

FYI guys don't freak out that much, KC > 0 is a "good thing". If the KC is not as high as you expect it's because the ECU found the highest safe timing below that. The system works as designed. We just all expect a "safe" tune to allow max KC, it means we're not even close to knock, and have even more timing "headroom" in case something goes wrong *which it does* as the engine ages.

 

That's not true.

 

I can set the DA table as high as I want.

 

On a straight up 3rd gear log with constant throttle, I would want NO timing pulled. Usually, that means I get timing pulled intermittently in 4th gear and sometimes when there is heat soak.

[2005garnetGT]

FYI guys don't freak out that much, KC > 0 is a "good thing". If the KC is not as high as you expect it's because the ECU found the highest safe timing below that. The system works as designed. We just all expect a "safe" tune to allow max KC, it means we're not even close to knock, and have even more timing "headroom" in case something goes wrong *which it does* as the engine ages.

 

any drop in KC from the map values indicate knock has happened

[boostsr20]

You folks are lucky that the Subaru ECU dynamically manages knock as well as it does or there would be lots of blown motors.

Unlike Mazda. Blown MS6's are starting to show up after mods with no ECU management.

[boostsr20]

any drop in KC from the map values indicate knock has happened

Thats what I thought. the ECU wouldn't pull timing unless the event has already happened. Its not a fortune teller ECU, it can't predict whats going to happen.

[2005garnetGT]

Unlike Mazda. Blown MS6's are starting to show up after mods with no ECU management.

 

know whats interesting? they use the same EM as we do, save for subaru's patented knock detection/control strategy.

[mickeyd2005]

I swear... I thought OP was using a Cobb OTS stage 1 ACN 91 Octane map. At least that's what we recommended at version 2.0.

[Legacy05]

Thanks guys .... contacted a good tuner down in Tucson ... now I just need to save $$ for a some dyno tuning time ... I'll do some logs tonight with the COBB OTS map to see how things look.

[Deer Killer]

That's not true.

 

I can set the DA table as high as I want.

 

On a straight up 3rd gear log with constant throttle, I would want NO timing pulled. Usually, that means I get timing pulled intermittently in 4th gear and sometimes when there is heat soak.

any drop in KC from the map values indicate knock has happened

 

The system is designed to ride the knock curve. It's not just listening to knock, it's listening to "noise" that is technically pre-knock. This is why there is a large gradient of KC, otherwise it would just panic and pull ALL timing advance when it heard knock. Also KC > 0 means it's ADDING timing because it's happy. "Pulled timing" would be KC < 0

 

Think about it, the ECU is pulling timing back with knock that is inaudible to human ears. I guarantee you if it was really knocking, you'd hear from inside the passenger cabin. I've heard it. Marbles + coffee can.

[mickeyd2005]

So, if my feedback correction was -8 and I was using a stock DA table with 4 in it, I would get KC = -4. To correct this, I can change my DA to 9 and reduce my base timing by 5 degrees. Now when my feedback correction is -8, I'll get a KC = 1.

 

So am I good to go?

 

No.

[rao]

That depends which tuner you work for

[mickeyd2005]

Also KC > 0 means it's ADDING timing because it's happy. "Pulled timing" would be KC < 0

 

Dude, you don't know what you are talking about.

[biz77]

That's not true.

 

I can set the DA table as high as I want.

 

 

Mickey,

Can you explain why someone would not want to set the DA (dynamic advance) table astronomically high to let the ECU probe the limits of timing?

 

I see a few "professional" tuners using a conservative base timing with very high advance numbers. Many cars logging with these maps can only manage to advance to 90% (or so) of the total timing, but are still seeing positive knock correction. What are the implications of running a map that has DA numbers that are unobtainable? Will IAM drop even if KC is still positive? What benefit does using the compensation tables provide over letting the ECU probe the the bounds of an aggressive advance table?

[Deer Killer]

So, if my feedback correction was -8 and I was using a stock DA table with 4 in it, I would get KC = -4. To correct this, I can change my DA to 9 and reduce my base timing by 5 degrees. Now when my feedback correction is -8, I'll get a KC = 1.

 

So am I good to go?

 

No.

 

1. Don't let a monkey lose in your ECU.

 

Yes, that's how it works. It's supposed to ride the knock curve, period. If the knock detection and correction routines work as designed, if your parameters aren't so fucked up as to not let you get appropriate timing, you'll run the SAME timing.

 

That said, the latter example should be safer (depending on the limits of the algorithms involved) as base timing works with worse fuel/conditions , so yes the KC = 1 does mean something different, even with the same timing result.

[2005garnetGT]

no, neither will be any safer then the other, the sum total ignition timing would be the same, 8 degrees less then what it should be.

[mickeyd2005]

http://www.enginuity.org/viewtopic.php?t=1840

 

unsubscribe.

[Deer Killer]

no, neither will be any safer then the other, the sum total ignition timing would be the same, 8 degrees less then what it should be.

dynamic, system, dynamic, system.

 

Looking at one point in time means little.

[2005garnetGT]

http://www.enginuity.org/viewtopic.php?t=1840

 

unsubscribe.

 

deerkiller, read this.