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Programable fuel injection?


Steve Smith

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If this is something the fuel injected models are capable of (PGM injection) , just exactly what was Honda referring to? I doubt Honda would claim the injection (ECU) can be "tuned" or reprogrammed  using aftermarket devices like a Power Commander.

I contacted GUHL performance in Ephrata , PA and asked them about doing a reprogram on my '01's ECU. I was told they couldn't help due the bike being too old. They also do NOT recommend using a Power Commander because they will eventually fail. I did have an older unit fail on a Kaw. GPz 750 Turbo at least 15 years ago. Left the bike in limp mode.

With my latest XX, an '01, already having a full Akrapovic system on it when I bought it recently, I'd like to think there is some way to reprogram my ECU so I can get the most out of the upgraded exhaust and not run the risk of it running lean .Don't  know how long the system has been in use on this bike, hopefully there are no burnt valves.

 

Steve

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It is absolutely programable, if you have the right stuff.  No clue if anyone outside of Honda has that stuff, but maybe.

 

I've not heard of Power Commanders having a high failure rate, but if the PC fails can't you just disconnect it and ride?  There's another device that just adds fuel, that one I know can be removed quickly and ride on the stock ECU.  It's adjusted using little screws on the unit, no computer needed.  Don't remember the name but will try to remember to take a look at it later.  You could also bump the fuel pressure with an aftermarket regulator, but I doubt that would be a good way to go about it.

 

I've never heard of lean damage from running an exhaust without tuning.

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So, what's the most efficient way to get the most out of a stock XX except it having a full system? Power commander? Hit or miss with it myself or pay for some dyno time and a qualified  tech to "play" with the PC ? Does a high flow air filter really help ?

Had a full Muzzy on my last XX (an '03 model), and no PC and using a stock air filter element. I had a free dyno session with it and a dealership special event and I seem to remember it made 136 hp . I'd think a full Akrapovic would make more power for the bike than a Muzzy. A realistic 140 hp. would be nice.

 

Steve

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It's an endless spiral.  Personally, I'm not dyno tuning something unless I absolutely must squeeze as much out of it as possible, as the costs per horsepower are staggering, IMO.  The Furbird was never tuned, and it had a 75hp direct port nitrous kit on it.  But the reality is, no matter how much money you have, there is ALWAYS somebody faster.  Bolt it on and enjoy it and don't worry about a number.

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Tuning it to make the most of what you have makes sense, but only you can decide if the cost is worth it.  If it runs smoothly and doesn't have issues you could just let it go as it is, no damage should come from that.  140 on that dyno won't be 140 on whatever dyno you strap it to tomorrow so I agree that you should probably ignore the number and only think about what feels like enough power for you.

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Only had one bike with a Power Commander and that was forever ago it seems. The new updated version is capable of what exactly? If someone here is familiar with how they work or what advantages it provides will help me decide if that's a direction I want to go.

My main goal with this XX is to pick up where I left off with Purple Plazma. It'll be my idea of a custom looking, show quality street legal and ridden bike , a bike that'll also do top speed runs and 1/4 mile passes at my local Drag Strip. Something that's a unique one-of-a-kind head turner and show winner.  At 63 and "retired", it'll most likely be my last major bike build. Can't wait until next season when it's finished and on the road.

I appreciate all the replies and help .

 

Steve

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13 years on my P/C 3, and no issues.  Only reason i got it was for a big bore kit, and a compression bump.  Have never tried to run it with out the P/C connected, but I might try it just for grins.

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PGM doesn't stand for Programmable Fuel Injection, it's Programmed Fuel Injection.  There's no inference by Honda that the ECU is user programmable, and its not.  To do so would require eproms/flash memory chips, and it doesn't have them.  The programming is permanent to the chips, at least until they reach their service limit and fail.  The distinction of "programmed" is just a different way to say electronic.

 

So with that in mind, the only way to alter the signals that the ECU sends to the sprayers and sparkers is with an add-on device.  You could modify the signals coming out of ECU, but those signals are "normal" and you'd have to basically build another ECU, and that's a lot of work.  So instead we can modify the signals going into the ECU, and let the already programmed ECU think the incoming data and output signals are be the product of the engine condition that we want the ECU to think exists at the moment...essentially that the engine is starved for fuel.  The most common way to do this is with a Power Commander, a device that has flash programmable memory and can modify the input signals to the ECU.  The sensors that send data to the ECU are extremely dumb and the data they send is about as minimal as it can get, so the difficulty with modifying that signal is also minimal, making the idea of the power commander simple, dirty, and effective.  Lie the right way to the computer, and you'll get it to put out what you want.  Sounds like a real-life situation, except it doesn't cost as much as other similar situations. 

 

I know its not uncommon to hear about Power Commander failures, but I wouldn't call them an unreliable device.  Maybe just not built to the same standard as the ECU, and often not properly mounted.  Anyway, the PC is simply a way to clean up your fueling map.  Its not nitrous, and won't do any more than a good tuneup would do for an old Chevy.  If you have the standard off-idle throttle lumpiness, a PC typically takes that away, or at least decreases it. So unless the throughput of the engine has changed significantly, there's no great need for changing the standard fueling map that's locked in the ECU.  Even a full exhaust doesn't scavenge enough to overrun the stock mapping.  Where the PC can help in those instances is with cleaning up the fueling map, which would require dyno tuning with an AFM.

 

Best performance increase is improving air flow, but the bottleneck is the head, not the intake or exhaust.  A trip to the flow bench and porting work is probably the most stable and useful expenditure for significant horsepower gains without sacrificing any of the solid attributes of the engine.....reliability, simplicity, and driveability/good performance over a wide rpm/load range.

 

Your bike won't run lean with a full flow exhaust.  If you burn a valve, its because adjustment was needed due to wear.

 

 

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21 minutes ago, rockmeupto125 said:

So with that in mind, the only way to alter the signals that the ECU sends to the sprayers and sparkers is with an add-on device.  You could modify the signals coming out of ECU, but those signals are "normal" and you'd have to basically build another ECU, and that's a lot of work. 

 

Best performance increase is improving air flow, but the bottleneck is the head, not the intake or exhaust.  A trip to the flow bench and porting work is probably the most stable and useful expenditure for significant horsepower gains without sacrificing any of the solid attributes of the engine.....reliability, simplicity, and driveability/good performance over a wide rpm/load range.

I have http://www.tficontrollers.com/Sportbike/viewproduct.asp?pid=33 which alters the injector signals after the ECU.  I think Carlos did a dyno tune on his 2000 BB at their place.

 

The ports might be a bottleneck, but the exhaust is definitely a factor.  The right system makes a noticeable power improvement over stock.  I also got to experience a wrong system and it sucked the life right outa the motor.

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Yep, didn't know you could still get them.  they just boost the signal to the injectors over a wide range....not too precise.   Good way to smell like unburnt gas all the time.

 

Everything's a factor....its a system.  The head can't flow with a tight exhaust, exhaust only flows as much as it gets from the head, intake limits the flow.........improving one rarely makes a big difference.  He's already got a good exhaust, so he can spend a grand on something else in the "flow chart."

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No offence, but it is Stone Age unit. iirc we are in AD2018. Power commander has rpm x load ( % of thottle opening) fuel cells. 12x12 I think. 

 Depending on the version it might have ignition table as well, but I would not mess with it on relatively stock motor. It is a old school engine with big intake ports. Velocity at peak rpm is  below 300ft/ sec. Modern engines relay on higher speeds, closer to 400 ft/sec.

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27 minutes ago, superhawk996 said:

I have http://www.tficontrollers.com/Sportbike/viewproduct.asp?pid=33 which alters the injector signals after the ECU.  I think Carlos did a dyno tune on his 2000 BB at their place.

 

Huh, they look more "pro" now.  Mine was inside of a cassette box.  Seriously.  But the dyno didn't lie, went from 142 to 149 *and* got rid of that lean blip slightly off idle.  There were no negative side effects.  Like Oscar said, it just adds slightly more time to each injector pulse, so it can't REMOVE fuel from the programmed curve.  But it also just stops working if it dies and doesn't affect the bike.  I'd recommend it.

 

I saw a UFO after leaving their place to ride home.  I'm certain it had nothing to do with being awake for 24 hours riding in the desert and sitting in a hot dyno room.

 

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Well DAMN! That's a lot for my simplistic mental capacity to absorb! Thanks to all for that important info pertaining to my query. I will definitely take that input  and put it to good use.

I know I can make my bike look fantastic, maybe now, I can make it run at it's fullest potential too.

 

Steve

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