The sharpest HD engine guy I know, has a saying about tuning.....

"You gotta give it what it wants".

No two are exactly the same and pipes, air filters, elevation, fuel grade, and on, and on...... all play into the equasion. So, what works for one... may or may not work for another. Some are more finicky than others, but one thing is for sure with all of them, and that is that when ya get it "right" you will know that your time was well spent.

 

Again, the trick and the correct way that I see in doing the conversion from the DTT to the TMax would be to CONVERT the MAP(kPa) positions from the DTT program to TPS that the TMax uses and THEN, apply them to the TMax for timings in the correct TPS vs. RPM. Anything less would be a dangerous application of timing from one program to the next, hence my initial reply. To me the current method is nothing but a hodge podge of guessing with application.

I'm not ******* anybody, and I commend your efforts, but if it would be this easy, I would have already used the timings from my SERT program and applied them to the TMax.................which again, I'm not saying cannot be done, but the conversion would have to be made.

 

Ok roughly speaking its relationship is approximately like this!
16 in-Hg = 2% Throttle
18 in-Hg = 5% Throttle
20 in-Hg = 10% Throttle
22 in-Hg = 20% Throttle
24 in-HG = 40% Throttle
26 in-Hg = 60% Throttle
28 in-Hg = 80% Throttle
30 in-Hg = 100% Throttle

 

I agree, but the air should be clear on what each fuel management system is. That being Alpha N vs. Speed Density, otherwise our communication ain't jiving. I left our last conversation in the past thread scratching my head because if the DTT uses MAP, then it "should be" Speed Density according to the exerpt..

 

Ding ding, exactly what I'm talking about..............if your conversion is correct.........this is the key to applying timings from the 2 different programs..............anything else is guessing. I've already given this subject much thought owning both the SERT and the TMax, believe me.

 

hell yeahh the sharpest guy gave my scoot what it wanted.... turns out its what i wanted too.......a great running bike....

 

From: http://www.daytona-twintec.com/tech_tcfi.html

__________________________________________

What is the difference between speed-density and alpha-N fuel injection control systems?


[blockquote]

The OE Delphi® system is a speed-density control system. It remains a speed-density control system even when devices such as the RevTech DFO, Dynojet Power Commander, or Screaming Eagle EFI Tuner are added. The TCFI is an alpha-N control system.

Speed-density control calculates air flow (and consequently meters the correct amount of fuel to attain the desired air/fuel ratio) based on engine RPM (the speed term) and manifold pressure and temperature (the air density term). Once calibrated, speed-density systems can accurately meter fuel as long as the manifold pressure is well behaved. Speed-density system are somewhat forgiving for minor vacuum leaks and inconsistent throttle body behavior. However, speed-density control cannot cope with the erratic manifold pressure characteristic of long duration, high overlap camshafts.

Alpha-N systems are typically used in racing applications where the camshaft characteristics preclude speed-density control. Alpha-N control calculates airflow based on throttle angle (the alpha term) and engine RPM (the N term). In addition, most alpha-N systems make a correction based on air temperature. The accuracy of an alpha-N system is highly dependent on consistent throttle body behavior and is adversely affected by any vacuum leaks. Adding closed loop feedback from a wideband exhaust gas oxygen sensor greatly improves the accuracy of an alpha-N system. The major advantage is that alpha-N control has no dependence on manifold pressure and is able to tolerate radical camshaft profiles.[/blockquote]

 

So from this I've setup my timing to be conservative. One thing I might look into is making each timing curve gradually slope down to 100% TPS. I'll have to pay special attention to when the drop begins since this will be the trigger to curb detonation. I'll run what I have for a bit to get more miles onit. Then I'll look into improving the curves.

I primary goal is to get the 2200 to 3500 rpm range in control with good pull andthrottle response. Then I will try to expand this upto 4500 rpms. I'm not too worried what high end performance I get at WOT. If I get this thing into the 80-90% satisfaction range, then I'll be very happy. I wasn't there when I initally installed the V&H Big Shot Duals - even after the 500 mile auto tune.

 

DTT uses MAP for timing management, not for fuel management. There are two functions being performed. Electronic ignition control and electronic fuel control. The EFI part is Alpha-N.

 

Darren.....
Let me try again... I was trying to answer that, but I probably strayed in my rambling.

The DTT does NOT use MAP for fuel delivery calcualtions. It it did, it would be a Speed Density device.
The DTT does read MAP and use it, in relation to RPM to manage TIMING.

The terms "Speed Density" and "Alpha-N" are used to describe fuel delivery systems (injector pulse width and spray intervals).

While ignition timing (when plugs fire)is part of the overall equasion and the controllers are housed in a common box, it is a totally separate control system thanthe fuel delivery system. DTT uses MAP for ingnition timing only - NOT fuel delivery. That does not make it a Speed Density system.

Sorry if my other post was unclear or ambiguous.