Tinkering with the throttle map

[NSFW]

But, again, the absolute value of the throttle plate is purely incidental to me. The stock throttle pedal response felt too steep down low and too flat up high, so when I saw the shape of the pedal-to-torque map I figured that making it flat would make it relatively less steep at low throttle pedal and relatively steeper at higher throttle pedal. And I got the results I expected, though I might have overshot a bit.

[merchgod]

But, again, the absolute value of the throttle plate is purely incidental to me. The stock throttle pedal response felt too steep down low and too flat up high, so when I saw the shape of the pedal-to-torque map I figured that making it flat would make it relatively less steep at low throttle pedal and relatively steeper at higher throttle pedal. And I got the results I expected, though I might have overshot a bit.

Yes, I see what you mean. I guess that would depend on the factory mapping. for example, the usdm 07 sti throttle mapping is so butchered that it is like a light switch - either on or off. So, unless someone likes that behavior and just wanted to change the relative behavior, they would need to look at both maps. But, the LGT isn't nearly that bad, at least for the 05-06 models.

[NSFW]

Thread resurrection. I'm about to start tinkering with the other map, too.

 

Anyone every get the impression at times that the accel/decel cruise control switch wasn't even hooked up? Whereas at other times, if you hit the accel switch the car accelerates hard? (I've watched it build boost at times, when accelerating in 5th.)

 

Yesterday I started watching the way the "memorized cruise speed" behaves and

I have a theory now that when cruising at low RPM/throttle (especially downhill) the cruise control speed adjustment is weak because the Requested-Torque-to-Throttle-Plate-Angle map is pretty flat down there. Whereas if you're cruising uphill at higher RPM and freeway speeds, the cruise responds aggressively because the map is pretty steep up there.

 

So now I'm thinking of linearizing that map too. Or maybe just decreasing the curvature by half, for starters.

[LittleBlueGT]

I know what you mean. And while it is a bit hard to explain I think you are on the right track.

[Yamarocket630]

Does anyone know if Racetuner for the AP has access to these same maps?

[mickeyd2005]

NSFW, you can try this one.

 

http://www.legacygt.com/forums/showthread.php?t=73843

[NSFW]

Thanks, I will.

 

Actually I have a requested-torque table now that I'm pretty happy with. The first version felt a little numb right off idle, which I eventually realized was due to the fact that it ramps linearly all the way down to 0. That would theoretically become 0% throttle opening, but if course the idle control takes over and gives a couple percent of throttle opening. So I made the requested torque map slope down to what would be a value of 40 in the leftmost column (that column however is set to 0). That works pretty well.

 

I've also created a soft rev limiter by setting the bottom rows to 6900/7000/7100 RPM and decreasing the values in the cells in those rows (fuel cut is now 7100). I think I ramped down too aggressively though.

 

I'm hoping to be able to floor it in 2nd and reach steady state at about 60mph without lifting my foot. No real reason, I just thought it would be neat. It just hit me that the right way to go about this would be to remove the soft limiter, do some data logging to find the right throttle plate angle to do that, and then ramp down to that percentage & RPM. Maybe next weekend.

 

I gave up on the idea of trying to 'fix' cruise control with the throttle opening angle table, I don't think the problems with cruise are related to the shape of that map.

[eqt2010]

NSFW, you can try this one.

 

http://www.legacygt.com/forums/showthread.php?t=73843

Nice, is it good for 5EAT as well?

BTW, I found that you put 10(stock one is 0) at Pedal Angle 0% between 800 to 4000 rpm. What's the purpose of that?

 

Thanks.

[mickeyd2005]

Nice, is it good for 5EAT as well?

BTW, I found that you put 10(stock one is 0) at Pedal Angle 0% between 800 to 4000 rpm. What's the purpose of that?

 

Thanks.

 

That's to slow down the deceleration of the engine.

 

It's actually a little bit dangerous. Maybe you should change it back to 0.

 

I know that 10 is pretty much the limit because it affects cruise control interpolation between the first two left columns. At very low throttle settings (for example going downhill on a freeway), too high a value will cause the cruise control to hunt.

[eqt2010]

Got it. I'll change it to 0 and see how it runs. Thanks.

[Yamarocket630]

The #1 reason I wanted to open source tune was to fix the throttle map to work like a non-linear cable throttle. For the record this isn't the first vehicle I've owned or driven with DBW, but I've HATED the throttle response of EVERY one.

 

I did not want a truly linear response. I wanted to be able to hold the accelerator steady and have the acceleration of the car feel constant from off idle until I lifted for the next shift and I think I've achieved that. As an added bonus, cruise control doesn't try to relocate my ass to the back seat when I use resume at highway speeds.

 

The 3-5 torque request in the 0 pedal column is to eliminate a bump feeling with the cruise control on hilly roads due to driveline lash.

 

http://i560.photobucket.com/albums/ss45/yamarocket630/LGT/torquerequest.jpghttp://i560.photobucket.com/albums/ss45/yamarocket630/LGT/throttleangle.jpg