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Additional power from aftermarket ecu?

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I am curious as to why (I have heard that) an after market ecu like Vortex will allow the engine to produce more power than a properly mapped stock ecu. Can anyone shed some lite on this, true or false and why?

Do you think it is just the quality of the processor and it's ability to flow electricity more efficiently?

I guess I need to study up on how the ecu actually works. When I worked for GM as a auto tech. the engineers would not let us inside of the ecu if we wanted their help. If we opened it up we were on our own and finding a diagram of the boards was almost impossible. Now I'm a little older and more curious.

Edited by kx450f63

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Vertex = Pistons

Vortex = ECU contoller

Does an ECU have it's own contoller?

Is that all you have or is there more?

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There is nothing in the aftermarket ECUs to make the spark better, only different.

Most after market ECUs allow for more agressive spark advance. This tends to increase power at high rpm at the expense of low rpm power. Most want a nice, flat power curve, few actually are on the peak all the time except drag racers. However, that dyno report with an increas in Hp and as well as the kick which is percieved as much more power is what the public wants. Just like with most pipes, giving more at peak is done at the expense of power down low. What all this means is an engine that made 20 hp at 3,000 rpm and 40 at 11,000 not makes 18 Hp at 3,000 rpm (a 10% drop) and now makes 44hp at 11,000 rpm (a 10% increase). So when riding, going from the 18 hp at 3,000 to 44 hp at 11,000 feels like a huge boost, when all you really did was rob Peter to pay Paul. Now, if you are such a good rider that you hae the suspension perfect, have your engine completely done by Ron Hamp, race in the A class and always win by at least half a lap, then maybe a ECU for you might make that win become 3/4 of a lap. For the rest of the world, it is just another sticker.

Now, some ECU's like the vortex, have multiple maps. This can be very handy for everyone and be worthwhile. A real mild map would make the low end grunt stronger, could make the power hit softer and the bike more manageable in the tight single track. Then when out of the gnarly stuff and back on the fire road, a lip of the map switch can return tyhe bike to snappy, sharp power.

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Actually, what the vortex ignitions typically do is advance the timing down low for better hit, then retard it up high for better over-rev. They usually raise the rev limit a little as well to take advantage of the extra revs. So they are shooting for improvements both low and high. You generally won't gain much peak HP at all compared to a well mapped stock ecu, but the improvement in performance can feel big, and be valuable to a skilled racer. It can also just sweeten the feel of the thing.

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There are several things an ECU can do but I have to say that a properly tuned ECU can out perform an equivlant aftermarket ECU... the problem lies in actually being able to tune the ECU to your specifications and this is where the aftermarket unit usually excels.

There are 400+ maps or parameters in most ECU's that can be altered. For instance, many ECU's have a per gear timing maps as well as per gear air / fuel maps. As imagined I would be able to fine tune the air / fuel mixture as well as the timing in every gear meaning I could program for better launch traction higher overall power through the rev range if the proper fuel is used to prevent detonation events or pre-ignition events which can blow up the engine.

This is just scratching the surface. I assume many aftermarket units tune several variables to increase power (such as the redline limitation) but this would vary from ECU to ECU. Also, don't confuse ECU with ignition box. A CDI ignition box will only alter timing curves while an inductive ignition can alter timing and dwell curves which can improve spark output as well as timing in an engine. I have noticed that several people are unfamiliar with which units they are running (CDI or Inductive) but each works in a very different fashion.

Some other maps off the top of my head, MAP or MAF sensor transfer functions, Alpha blending, timing or A/F when rolling in and out of the throttle, solinoid controllers such as exhaust controllers, injector pulse width, coil dwell time, maximum rpm, torque management... and the list goes on and on... each bike is a little different. We are hoping to have some stock ECU tuning software in the future, but we are working on getting it to everyone. :thumbsup:

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Take a look at this graph:

powerout.gif

Depending on air fuel mixture (AFR), you can achieve optimal power, emissions, or economy.

Compare it with this graph:

fueleffic.gif

If you tune for more power, you will sacrifice efficiency.

Stock ECUs generally tune for a balance of economy and emissions at cruise and more power during acceleration and WOT.

Here's a typical AFR map:

afrtable.GIF

This will give you good fuel economy during cruise. You could get more power by choosing an AFR closer to 12.5 at lower RPM and load.

That's what I do on my bike.

There are RPM/load spark maps as well.

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If you tune for more power, you will sacrifice efficiency.

This will give you good fuel economy during cruise. You could get more power by choosing an AFR closer to 12.5 at lower RPM and load.

Just as a heads up.

Generally the leaner you go the more the power you will make. I've seen some stock bikes as lean as 17:1 or more. (that is 17 parts air to 1 part fuel)

Also, nobody is concerned about emissions with a bike, there are no provisions on the engine, such as catalytic converters and exhaust gas recirculation valves to warrant any emissions purposes in the ECU. There are also no government rules that regulate it.

Going leaner and advancing timing make the engine more efficient, the problem lies in how lean and how much timing can the engine take without going boom. Usually OEMS tune for reliability reasons and a smooth ride, clean powerband etc.

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Generally the leaner you go the more the power you will make. I've seen some stock bikes as lean as 17:1 or more. (that is 17 parts air to 1 part fuel)

Where are you getting your information? Yes, some engines run lean cruise up to 17:1 AFR to achieve greater economy, but they will produce far more power closer to 12.5:1 AFR. Greater power is produced on the rich side of stoichiometric, not the lean side. More importantly, if you run 17:1 AFR at WOT, the excess oxygen in the cylinder will combine with a hot aluminum piston and turn it back into ore. :thumbsup:

Also, nobody is concerned about emissions with a bike, there are no provisions on the engine, such as catalytic converters and exhaust gas recirculation valves to warrant any emissions purposes in the ECU. There are also no government rules that regulate it.

It depends which government you are talking about. Most US states don't regulate motorcycle emissions, but I'm not so sure about California or some EU countries.

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Where are you getting your information? Yes, some engines run lean cruise up to 17:1 AFR to achieve greater economy, but they will produce far more power closer to 12.5:1 AFR. Greater power is produced on the rich side of stoichiometric, not the lean side. More importantly, if you run 17:1 AFR at WOT, the excess oxygen in the cylinder will combine with a hot aluminum piston and turn it back into ore. :thumbsup:

It depends which government you are talking about. Most US states don't regulate motorcycle emissions, but I'm not so sure about California or some EU countries.

We tune automobiles professionally for a living my friend so this is first hand information. The only reason 14.7:1 A/F is ever used is because that is the air fuel ratio required for the catalytic converters to catalyse the mixture and clean the exhaust emissions up, not because of improved power. In a motorbike this is not a factor and never has been of any sort. Running rich or lean will create different emissions which are both harmful to the environment unless you have a catalytic converter and an oxygen sensor that can report A/F to the ECU.

Also, any motorized vehicle will make more power at leaner mixtures even at full throttle. The reason supercharged and turbocharged applications (which I am assuming is where you are getting your information) runs at 12.5:1 at wide open throttle is to make sure the combustion event doesn't detonate and blow up the engine. For all intensive purposes running leaner will always net more power but at the cost of reliability. Some hardcore guys run closer to 13.5:1 that are pushing it on regular high octane (92) gas.

To further improve performance, as lean as possible will always net more power as long as the combustion chamber design and ignition system can properly light of the mixture. Because of the engine loads and advanced head design in a bike it's not a problem to go really lean even at wide open throttle.

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Generally the leaner you go the more the power you will make.

:thumbsup:

What ratio's do you normally see peak power?

I typically play with 2 strokes, but my current engineering project has a cam and valves. Been performing fuel hooks at all sorts of loads and rpm trying to balance power and emissions. I've been seeing peak power right around 13:1 everywhere.

air-fuel-ratio-vs-power-economy.gif

I do agree, you can go much leaner at part throttle, steady cruise.

As for making more power, there's a crazy number of things many ECU's or even CDI's can be programed to do. I know many small engines the ignition will monitor revolutions, and if it sees the engine trying to accelerate over "x" number of revolutions it will kick into a different timing curve to help acceleration. So even without throttle position inputs it can alter away from a straight timing curve. They'll do things for come down, idle stability, cold starts, etc etc. More peak hp on a dyno? Maybe not. An overall better running/performing engine? Definitely.

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We tune automobiles professionally for a living my friend so this is first hand information.

Fair enough. Have you personally tuned engines or do you work in a different department?

I fuel injected my bike and tuned it entirely myself. I built the ECU (Megasquirt), fitted a Yamaha YZF-R6 throttle body, I even designed my own fuel pump control system to reduce power/avoid fuel return lines. I installed a calibrated Innovate wide band O2 sensor, so I log the AFR during all riding conditions.

My bike will not even idle properly above 15:1 AFR. I have data logs to show that my bike produces more power on the rich side of stoich.

You are entitled to your own opinion, but what you are saying is not consistent with my direct experience.

I do agree, you can go much leaner at part throttle, steady cruise.

:thumbsup: That's where you can achieve good economy. From everything I have read, you want to avoid lean mixtures at WOT. I will admit that I have not personally tried lean mixtures at WOT because it sounds like a potentially expensive experiment :worthy:

I know many small engines the ignition will monitor revolutions, and if it sees the engine trying to accelerate over "x" number of revolutions it will kick into a different timing curve to help acceleration. So even without throttle position inputs it can alter away from a straight timing curve.

That's an interesting trick. I have a throttle position sensor, so I use that for acceleration/deceleration enrichment. It makes a big difference. I also use rich mixtures with low TPS/high RPM to avoid decel popping. If I don't do that, I will hear about it from the neighbors :confused:

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i have never heard anything but 12.5:1 being the ideal ratio for power, since i can remember, for N/A motors, from many different sources, many being automotive. i dont get the 17:1

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My Daytona IROC R/T turbo makes the best power at 17:1. All people say it's mad but it is an insane 1/4 mile rocket that has been very reliable. The heads are a Lotus piece.

My highly modified naturally aspirated 400hp Mustang makes the best power at about 13.9:1 at wide open throttle and I loose about 15 horse going to 12.5:1

For street (crotch rockets) bikes, I noticed that Hondas run scary lean and that I have to richen the mixture in a similar Yamaha by about 5 percent or it won't run. The kawi's run best with another 5% fuel over the Yamaha's.

Also, I've tuned several Mustangs, several import cars (Mitsubishi 3000GT, Toyota Supra Turbo, 300ZX, Honda Civics with B16 etc engines), Trans Am's, Camaros, Chevy Trucks etc etc etc... and am very familiar with engine management on Chevy and Ford.

msiddalingaiah, if your using a megasquirt I would suggest buying a low impedance injector driver because high impedance units are not proper for bikes at high rpm. It may be partially to blame.

I have come to somewhat of a conclusion that head design, intake swirl and mixture in the combustion chamber will determine how lean and effective the engine will run. Typically leaning it up a bit does help power production, that is until the mixture doesn't ignite or you run into detonation due to hot spots in the combustion chamber. I believe based on my experience that the ignition system also plays a major factor in how lean you can push the engine before power starts to drop off. This is because in testing a perfectly tuned Corvette, where we couldn't get leaner or more power out of, with our high output spark plugs we were able to go even leaner gain about 4hp through the band and extend the powerband by about 500rpm (where it picked up about 8 or so hp). My assumption is that the mixture needs to be at the spark gap, and well atomized. It seems that a longer, bigger spark gives the extra needed energy and time to help counter that issue.

So in short, leaner if possible but without causing adverse conditions such as detonation, pre ignition etc. BTW I am sure you guys are on the ball with your rides.

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My Daytona IROC R/T turbo makes the best power at 17:1. All people say it's mad but it is an insane 1/4 mile rocket that has been very reliable. The heads are a Lotus piece...

Are you sure your WB O2 is calibrated correctly and your DAQ is accurate?

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Are you sure your WB O2 is calibrated correctly and your DAQ is accurate?

:smirk: I'm fairly certain. lol, like I said, doesn't make sense does it?! I'm guessing the turbo does it's job pushing the fuel to the spark gap. I will say that this car does show signs of spark blowout much quicker then most others I have played with.

EDIT - Just thought about this.... it's probably due to my external wastegate on the turbo cars bypassing some of the exhaust. :/ My bad!? The wastegate is vented to freeair and is connected to the collector on these apps (where the O2 is also connected) In thinking some more I am sure once that happens the sensor is picking up some of that air.

I suppose based on all this ~12.5 - 13.9 A/F is the best ballpark.

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When I jet a bike based on A/F ratio, there are three different numbers I look for

Idle - Classic 12.8/1

Off idle and below WOT 13/1 - a little lean, AP feeds the need of the throttle is opened. Also, if say you hold the throttle steady at say, 1/4, the engine rpms will rise and rise, sometimes right to the limiter, so what looks lean, really is not.

WOT 12.5/1

Looks rich at WOT, right? The reason is most bikes are not run at sustained WOT, the throttle is nailed, the engine revs build, the AP squirt is consumed and often, there are more rev's to build under load so a richer mix is called for. A drag bike? I'd nail the 12.8/1 as they are rev'd (no load) to the limiter at the start and throttle is not closed till the end. Clutch and tire slippage is used to keep the engine at peak.

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When I jet a bike based on A/F ratio, there are three different numbers I look for

Idle - Classic 12.8/1

Off idle and below WOT 13/1 - a little lean, AP feeds the need of the throttle is opened. Also, if say you hold the throttle steady at say, 1/4, the engine rpms will rise and rise, sometimes right to the limiter, so what looks lean, really is not.

WOT 12.5/1

Interesting.

Assuming non-drag bikes, is this what you are saying?

Off idle below WOT: 13 without AP

WOT: 12.8 without AP

WOT: 12.5 with AP

I'm at 12.5 in a lot of places on my bike and believe there's more power there. I was planning to go closer to 13 without AP to see if it helps.

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Whatdayado, you scambled my numbers!

In most cases, dirtbike/4S thumpers are very happy at 12.8/1 That would be a great goal if... we never used the throttle. Drag bikes do not use the throttle. They idle or go flat out. I mentioned tham as an extreme example. We vary our throttle, we have relatively massive bore carbs. When we nail the throttle to cross that log, we have a huge drop in acuum signal at the venturi, it is almost like airflow stops. The dreaded bog. So... we get a AP, it has about a one second duration though it starts a bit slow and tapers off at the end. Assuming we are in the right gear (not idling in 5th at 2 mph and hold the throttle wide open, expecking miracles) the AP should last long enough. Under max load siuations, we have to run a rich mix. So when you dyno your bike with a AF sensor, you will appear rich on the needle but it is smoke and mirrors, you are rich because of the AP. To get an accurate reading at part throttle, you have to disable the AP. You have to hold the throttle steady. You have to arbiraily figure out what throttle opening is correct foa a RPM. You hold the throttle at that point, and apply load to the engine until the RPMs drop to where you feel (the black art part) they should be. Read the AF. If it was right, it would be just about 12.8/1, perhaps a touch richer. WOT is easy to test for on any dyno. AP disabled, you roll on the throttle Watch the power rise, then fall off. Read the A/F at the peak. If you were dragging, you'd aim for the 12.8, but we go slightly rich perhaps to 12.5/1 , because... our loads vary, we are not having the load controled by tire slippage and clutch action, ours is controlled by widowmaker hill. The one place we can hit the numbers is idle. So with no AP, you run a tad lean on the needle, the AP will make you 'rich on the needle'. That is the appx. text book concept. Real life can and often is, slightly different. In real life, you jet for what appears to be a flat power curve on the dyno. Then you test ride, then you read the numbers. Now, the next bike of if air dnsity changes, all you have to do is hit the mumbers and the bike will perform like you want it to.

I think you have a good handle on it. Note what I bolded.

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I have one of these on my new YZ250f

Like anyone ,I had doubts. They do have a guarantee.Anyone starting a company in these times are going to make sure it works to some extent or they wont even get their investment back.

It wont allow me to start in 3 gear. It wont help me back flip.It wont lower my lap times by 7 seconds.

It does help my bike start right up when its hot. It does help my bike run like its ment to. Its a sharp point on a pencil.

For 200 in change my bike runs much better than the 700 dollar exhaust I put on my last years bike. To me not just any one part is the answer. Its the sum of the parts.

For the guys that are picking it apart. You should not buy one. You wont be happy. You should send your head to be ported. Get a new cam.Go for the pipe while your at it.And keep your bike running when you drop it in a corner

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