Closed-loop vs Open-loop

[Cliff]

They use a ($2500usd) gas analyzer, often on the factory bungs that the OEM uses (on Guzzi, etc.) to pull from. All technicalities aside, it works very well.

 

I look forward to being able to test one of your units on the dyno.

I've seen a few similarly priced analysers here and I'm reassured by the fact that some of them are using the same $200 sensor as I am on my bike.

 

Seriously, if you'd like to have a look at one of my units I'd be happy to ship you a unit for evaluation. You'd just need to ship it back promptly if I require it. You won't notice a difference on the dyno. I don't claim to be able to produce more power than stock. That is not really a function of the ECU. The motor defines the power, the ECU just helps you achieve it.

[Guest Jeff in Ohio]

Very good question indeed !

 

I will also throw in here my "old" question : How do you adjust your map correctly in the mid range (partial throttle) if you are using an inertia type (not brake type) dyno ? I still have the impression that inertia type dynos simulate mainly the full throttle acceleration situation. Please advice if this is not correct interpretation.

 

BTW, more advanced ECUs allow the user to decide what parts of the map are used in open-loop or closed-loop mode. The most advanced ECUs even allow to key in different lambda targets for different parts of the map.

 

br, JuhaV

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Ummm, the powercommanders are set up on a Dynojet 250i dyno that has an eddycurrent brake on it that makes it a load control/absorption dyno NOT an inertia dyno. They are pretty cool to watch. The operator can hold the bike at say 40% throttle, then use the eddy current brake to drag down the engine RPM to anything he wants to simulate any load condition such as going up a steep hill. So, it will do part throttle cruise, very well even! read on.....

 

http://www.dynojet.com/motorcycle_dyno/250i_dyno/index.php

[JuhaV]

They use a ($2500usd) gas analyzer, often on the factory bungs that the OEM uses (on Guzzi, etc.) to pull from. All technicalities aside, it works very well.

...

You are correct. You cannot properly map on an inertia dyno. PCIII mapping is only by Eddy current load-cell, air/fuel dynos.

...

ToddGuzziTech.com

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Thanks Todd and Jeff in Ohio,

 

I suppose that the gas analyzer could also be something more advanced than just a lambda probe ?

 

If the dyno is a load-cell type dyno, then I believe that the bike can be held at steady state to find out perfect settings for each load & rpm situation. Sounds good. A reasonable amount of test points around the map should provide very well tuned map.

 

If the tuning software is clever enough, it could also make part throttle accelerations (to simulate real life situations ) to find out the best settings to serve both steady state cruising and accelarating.

 

Need to find out the closest Dynojet Tuning Center to me <_>

 

br, JuhaV

[RacerX]

I suppose that the gas analyzer could also be something more advanced than just a lambda probe ?

 

If the tuning software is clever enough, it could also make part throttle accelerations (to simulate real life situations ) to find out the best settings to serve both steady state cruising and accelarating.

 

Yes it is, and yes it is/does.

 

I assure everyone the air/fuel gas analyzer is *MUCH* different then any "$200 sensor". Thanks for the comments also Jeff.

 

Cliff, I will take you up on your offer within the next few months. I can always act as a shipping source for this unit here in the U.S. as well.

Did Dave Blunk/Sport Cycle Services (Santa Barbara) get the computer issues resolved on his 1100 Sport race bike? I was at Laguna Seca this year, standing amongst them.

 

ToddGuzziTech.com

[Cliff]

I don't hear much from Dave and his team. I've called him a few times to see how he's going.

He's making progress and is happy with his unit. His main problem is getting enough fuel into the bike. He needs to up the fuel pressure or get larger injectors.

[dlaing]

I don't claim to be able to produce more power than stock. That is not really a function of the ECU. The motor defines the power, the ECU just helps you achieve it.

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I don't understand why you would not claim that.

You seem to be splitting hairs about whether the ECU or the motor define the power.

But the ECU is a big part of the picture.

The stock ECU does not appear to be well optimized for power, or efficiency.

From what I have seen of before and after PCIII, the map is changed so that more power is gained. Sometimes the gains are minimal, but there have ALWAYS been gains from Guzzis who have dynotuned with the PCIII.

Of course the biggest gains occur when the PCIII is use to correct the mixture for modifications such as aftermarket mufflers.

My 2000 V11S had a 2 into 1 exhaust system that made huge HP gains after remapping.

See:

http://www.scripps.edu/~dlaing/v11s/DL_V11S-vs-StockV11S.jpg

for the dynochart.

The mixture with the stock ECU was as bad as 17:1, I was lucky not to burn a valve.

Granted that if you have stock mufflers and are tuned properly, your mixture will not be off by THAT much, but I would be very suprised if a stock Guzzi was producing maximum HP at all RPMs.

And of course, the greatest benefit of re-mapping is not the HP, but how well the bike runs.

Todd's website is packed with testimonies:

http://www.guzzitech.com/PCIII-Endorse15M.html

As I hope that yours will also someday be:

http://www.jefferies-au.org/My16M/My15M.htm

FWIW I see the My15M as being a better solution in the long run because I see one ECU as being more reliable than both an ECU and a PCIII.

I also suspect that the PCIII could be used in conjunction the My15M to quickly zero in on an ideal map.

 

Regarding the loop issue, I like the idea of adding fuel monitors such as those from K&N.

With these fuel monitors you could monitor changing conditions and how they effect the mixture. As good as the PCIII tuning link is, it does not produce a map for every condition. (Although it does measure temperature, air pressure, and humidity to theoretically optimize the map) On board feedback could be a good thing.

Closed loop on a lambda sensor could also be a good thing as long as it does not create lean surging and unpredictable rideability.

[RacerX]

I don't hear much from Dave... I've called him a few times to see how he's going. He's making progress and is happy with his unit. His main problem is getting enough fuel into the bike. He needs to... get larger injectors.

 

Better call him again... and when you do, might mention to him that I have larger injectors for my big-bore project sitting here in the box. I can get them/more any time.

 

I see the My15M as being a better solution in the long run because I see one ECU as being more reliable than both an ECU and a PCIII.

As good as the PCIII tuning link is, it does not produce a map for every condition. (Although it does measure temperature, air pressure, and humidity to theoretically optimize the map).

 

Like how much more reliable then the 100k+ miles on my Jackal? Heh, yeah, better tell those idiots at Magneti/Marelli and Dynojet they have no idea what the hell they're doing.

 

See you at the SD Rally David - no excuses for not showing atleast on Sat.

 

As always, my $.02,

ToddGuzziTech.com

[luhbo]

Sorry what I meant to say is that since the PCIII isn't adding wiring, cylinder mapping can only be possible if the ECU has separate injector trigger wires.

 

Chris

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This individual cylinder mapping provided by the PCIII really looks interesting, the more as the WM ecus IMHO do not know such a

 

feature.

 

As I have understood the PC concept this unit is just cheating the ecu by modifying the sensor values. So the possibilities it has directly depend on the sensors that the bike offers. In this special case it would mean that after the first injector has fired the reading of let's say the pressure sensor has immediately to be faked so that the ecu thinks it has to provide more juice with the next injection.

 

Now what will happen when our italian fellows at Magneti Marelli and/or Guzzi and/or Aprilia just change the charakteristics of their sensors, what they do sometimes, or deliver european ecus with US software in swiss bikes, re-imported then to maybe the netherlands? These scenarios always did and do happen, it's just the genius of the italian manufacturers that nevertheless always great bikes were put on their wheels, regardless what actual version of wire-harness was used in september to fit the ecus they had at hand then.

 

It seems to be a great job what the aftermarket suppliers do to stay on the ball in this game.

 

Hubert

[Guest Jeff in Ohio]

As I have understood the PC concept this unit is just cheating the ecu by modifying the sensor values. So the possibilities it has directly depend on the sensors that the bike offers. In this special case it would mean that after the first injector has fired the reading of let's say the pressure sensor has immediately to be faked so that the ecu thinks it has to provide more juice with the next injection.

 

 

Hubert

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ummmmmmm, NO. The PCIII has a map of injector adjustments based on RPM and Throttle Position - it does not care about the temperature or pressure ofthe air around you. A dyno is used to determine these fuel values in the table. The PCIII then looks up the appropriate fuel mod from this table based on current throttle position and engine RPM and then changes the output signal to the injector. The original ECU still makes all temp and pressure compensations as normal. It does NOT change the sensor input into the original ECU. The original PC2 did that, and they never did make PC2's for Guzzi's. Dynojet quit the whole sensor cheating thing after motorcycle makers programmed their ECU's to reject 'abnormal' values such as when the PC2 might give it. The PCIII monkeys with no imputs, just the injector output signal from the ECU......

 

Plain and simple IT WORKS every time, all the time.

[luhbo]

Plain and simpel, in fact! That's easyier then I thought. You just use the original injection impuls as a trigger for your own injection signal. And the lenght of this signal is not calculated, it's just read out of a map. That's what one could call a hack! So it seems that the decision of the OEMs to stop others to fool their ecus made things even better for those.

 

Anyway, this foolproof system should make it a bit difficult to alter spark-advance, shouldn't it?

 

On the other hand, if things are so straight forward, wouldn't it be possible to offer the possibility to use more than just two maps (two means those for the cylinder offset)? More than those 2 would give you the possibility to switch between a highload configuration, an economy configuration and maybe also a quite lean/rich traffic-control configuration which could make your mufflers sound a bit less italian!

A standard 32K eeprom should provide enough space for quite some maps like this, with no additional costs!

 

Hubert

[RacerX]

Plain and simple, in fact!

 

Anyway, this foolproof system should make it a bit difficult to alter spark-advance, shouldn't it?

 

On the other hand, if things are so straight forward, wouldn't it be possible to offer the possibility to use more than just two maps (two means those for the cylinder offset)? More than those 2 would give you the possibility to switch between a highload configuration, an economy configuration

 

Hubert, I am working with Dynojet as I write to offer a "Timing Module" plug-in, though from all the preliminary testing we did over a year ago, most stock bikes showed no measureable gains to make it worth the time and effort. About the only thing it will be good for, is to dial out some of the 'ping' issues (in the warm weather months) for some of the V11S owners (that have this), and perhaps the few that have modified their motors.

 

The Yoshimura EMS (built by Dynojet, not for Guzzis), uses multiple map selections via a handlebar mounted switch. Dynojet decided to keep it simple, and only store "one" map with the PCIII (though, yes it is quite capable of alot more). You can easily change the mixture on the faceplate while on your ride, or you can swap maps via PC software (once you have diffrent maps built at a Tuning Center).

 

Read my write-up here; http://www.guzzitech.com/PCs-Todd_E.html

More; http://www.guzzitech.com/PCIII.html

 

Any other questions, please e-mail me direct.

ToddGuzziTech.com

[luhbo]

Hi Todd,

 

at this point I'd like to thank you and the other guys here in this forum for your will to share your knowledge and feed really substantial information also in topics like this one, and doing this regardless what opinion you have and wether you see things different or not.

It is really a pleasure and most interesting to be here and read through the posts. This goes to Jaap also, of course, hosting this site.

 

Hubert

[RacerX]

Hi Todd, at this point I'd like to thank you and the other guys here in this forum for your will to share your knowledge and feed really substantial information also in topics like this one...

 

Hubert, my pleasure... though honestly I prefer to discuss this "tech" type stuff on GuzziTech.com's Webboard for obvious reasons, but when non-factual information gets posted, I often feel it's necessary to put my $.02 in... instead of watching people wander on/debate mis-information.

 

ToddGuzziTech.com

[Guest JohnInNH]

Todd... Please let us know when the new PC-IIIr usb is out for the Le Mans