Up to 6 HP, 6 lbft Torque ... $349
01-24-2007, 07:52 PM
#13
AudiWorld Super User
Thread Starter
Let me clarify
Normally, with most other ecus, you expect that adaptation improves performance, and that the default settings will reduce performance. This is the way it generally works on the ME 7 ECU. (Tony, you can correct me if I'm wrong, since you're pretty much an expert on the ME 7.) This raises quite a few questions which are not yet answered.
The ECU in the RS4 is the MED 9.1, originally designed for FSI in the stratified mode, and now neutered in the US, because of our crappy, high sulpher fuel. I wonder about things like "did neutering for the US market cause problems with adaptation?", or "is there something fundamentally different about the way this ECU works, than previous generations?", or "how can we figure out how to exploit this ECU without having it re-adapt itself.
Common strategies for improving power are to change the high torque fuel delivery and timing advance tables, but that always assumed that the ECU was running open loop and could not adapt away the gains. That fundamental assumption may be wrong for this ECU. We actually "see" the ECU adapting fuel trim and timing at WOT.
Part of the point of the post is to point out that there may very well be a "reason" why some engines dyno or perform lower than others. There could possibly be something that causes timing to be retarded further than necessary, or fuel trim to be increased beyond what is normal. (This might have implications for oil fuel dilution.) The second is to set the stage for real benchmarks between stock and aftermarket exhaust. Claims like 20 HP increase over stock for exhaust system M, may not hold water, if the ECU was at a different state in each test. If we can force a known high performance state, we can perform apples-to-apples comparisons reliably.
Anyway, if you're going to run your car against another, or test performance on a Dyno, or with a FATS run, it would probably make sense to reset the ECUs before you do.
Oh, and to answer that question about when for the Millteks ... mid March, after the possibilly of New England nasty sandy salty roads has mostly gone away.
The ECU in the RS4 is the MED 9.1, originally designed for FSI in the stratified mode, and now neutered in the US, because of our crappy, high sulpher fuel. I wonder about things like "did neutering for the US market cause problems with adaptation?", or "is there something fundamentally different about the way this ECU works, than previous generations?", or "how can we figure out how to exploit this ECU without having it re-adapt itself.
Common strategies for improving power are to change the high torque fuel delivery and timing advance tables, but that always assumed that the ECU was running open loop and could not adapt away the gains. That fundamental assumption may be wrong for this ECU. We actually "see" the ECU adapting fuel trim and timing at WOT.
Part of the point of the post is to point out that there may very well be a "reason" why some engines dyno or perform lower than others. There could possibly be something that causes timing to be retarded further than necessary, or fuel trim to be increased beyond what is normal. (This might have implications for oil fuel dilution.) The second is to set the stage for real benchmarks between stock and aftermarket exhaust. Claims like 20 HP increase over stock for exhaust system M, may not hold water, if the ECU was at a different state in each test. If we can force a known high performance state, we can perform apples-to-apples comparisons reliably.
Anyway, if you're going to run your car against another, or test performance on a Dyno, or with a FATS run, it would probably make sense to reset the ECUs before you do.
Oh, and to answer that question about when for the Millteks ... mid March, after the possibilly of New England nasty sandy salty roads has mostly gone away.
01-24-2007, 08:01 PM
#14
AudiWorld Super User
Thread Starter
I'll be monitoring timing and fuel trim
Now that we know it occurs (thanks to Tony of EPL) it's actually quite easy to monitor with VAG-COM. In a future post, I'm sure I or someone else will have an answer to that question.
BTW, the cable does have active electronics in it. However, I get your point, it is just a "cable." The market for that "cable" is pretty small, so I can understand the high cost to recover design expense and make a profit.
BTW, the cable does have active electronics in it. However, I get your point, it is just a "cable." The market for that "cable" is pretty small, so I can understand the high cost to recover design expense and make a profit.
01-24-2007, 08:03 PM
#15
AudiWorld Super User
Thread Starter
It's a software reset
It's occasionally done at the dealer, and it's much kinder and gentler than pulling the battery, since the pulling the battery will reset things like the Nav system, which will require that silly activation key that we can never find.
01-24-2007, 08:14 PM
#16
AudiWorld Super User
Thread Starter
Not sure, but S4 V8 may only have one ECU, instead of two
I think the RS4 required two because of the additional software overhead of FSI control. But I'm just guessing here.
There are significantly more elements of this engine under closed-loop control than previous engines from Audi. With FSI in Europe in the stratified mode they have to be able to control Air-Fuel mixture with the injectors and fuel-rail pressure, while the throttle body is wide open. Torque in this mode is solely controled by fuel delivery, by varying pressure and injector duration down to 1 ms. This increases the real-time control load on the processor significantly.
There are significantly more elements of this engine under closed-loop control than previous engines from Audi. With FSI in Europe in the stratified mode they have to be able to control Air-Fuel mixture with the injectors and fuel-rail pressure, while the throttle body is wide open. Torque in this mode is solely controled by fuel delivery, by varying pressure and injector duration down to 1 ms. This increases the real-time control load on the processor significantly.
01-24-2007, 11:56 PM
#19
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It's the license and software upgrades you're paying for...you can get hte cable on ebay for 30 buck
s but the fact is, you're not going to have the vag-com software you need. Yes, I had the option of getting some cracked software, but it wasn't worth it. I figure i'd have some VAG car to vag anyway...
