WOT shifting for autos

[SVOboy]

I've tried this with the scan gauge and there is a sweet spot where MPG drops from 6 to 2.8 with out much increase in acceleration.

Excuse me kindly, but I am a bit confused on this part.

What I take from the whole, however, is that WOT or near WOT shifting has been tested by you with your scangauge to yeild a slight benefit?

[zpiloto]

When I am near WOT the scan gauge shows a slight increase in MPG. This info comes from only 2 runs. If I accelerate hard the scan gauge will show 6 MPG then if I floor it the MPG drops to 2.8 MPG with out much increase in accleration. Just for reference time to 50 mph is about 11 seconds.

[rh77]

Unless modified, I think Hondas run in open-loop under WOT (unless modified not to). You may want to consider like 80% throttle input.

RH77

[SVOboy]

I've scrapped this because even with no kickdown cable if I go WOT it just rev up to 3k quickly and sits there through acceleration, time to swap the manual in,

[Compaq888]

after I adjusted my throttle cable and took out the extra fluid from the tranny it's shifting right. In fact after I reset the ecu it doesn't jump between gears when going up hills. Even when racing now if I shift it at 6000rpm it goes right for the redline(6100) and shifts into the next gear. I think the ecu has a lot to do with shifting too.

[rh77]

Originally Posted by Compaq888

I think the ecu has a lot to do with shifting too.

Huh. Thought it was mystical powers that shifted the transmission, like a leprechaun or something. Dammit, now I'm going to have to cancel the Warlock that was going to wave the magic wand to change the shift points.

RH77
"They're Always After Me Lucky Charms!"

[Compaq888]

try reseting your ECU RH, and your tranmission module too.

Resetting the ecu is easy, just follow instruction on ecu itself. The transmission module reset has a lot of steps including turning the key a lot and pressing the gas pedal in special modifications.

After I reset my ecu my shifting got so much better. 1st gear grabs better, stays in 4th when going up small hills, and when racing it shifts hard and fast and goes all the way to redline.

[rh77]

I posted this a while back, and didn't get a idea on if it worked. In the TL, the manu-matic shift allows you to select a gear and hold it despite pedal pressure. You can't put it in top (4th) gear until a certain speed.

With that in mind, I generally stay in the highest gear and nearly floor it most of the time to accelerate. Since I can't test economy on that car right now, is it better to stay away from WOT because of the Honda open-loop circuit in that situation, or stay with 80% throttle at top gear? Furthermore, at 35 mph, in 4th gear, accelerating up an on-ramp to the highway seems like it would take a toll on the transmission -- it's at 1500 RPM, WOT, and steadily increases in speed until 60-65, then the TC kicks in. Is there slipping going on? I've heard though that more throttle means more ATF pressure to the selected gear (I've had some low-throttle, hi-load, low 3rd gear fluid pressure CELs now and then -- maybe like every 6 months). That's kinda why I'm worried about the tranny (and with the history of the 5-speeds in 2000-2004 in the TL (especially the Type S) and the MDX. I lucked out and got the 4-speed. I've heard of 5-speeds lasting 40,000 miles even after replaced new. This is, by far, the biggest smudge on the clean record of Honda reliability.

RH77

[red91sit]

welll this is a tricky topic, all the companies use differnt programs to control their auto's and engines. Whats' best for one car might be very different for another. My car's auto tranny is completely seperate of the motor, I found best economy to be had by giong 50% throttle, and then letting off the gas to make it shift, then getting back on the gas haha, works great,

[GasSavers_BluEyes]

Originally Posted by SVOboy

However, since I no longer am able to use my kickdown cable (tells the tranny when to shift based on pedal pressure)

Be careful with this. I'm not familiar with the Honda transmission, but I know that other manufacturers use the throttle cable to not only determine shift points, but also to regulate transmission fluid pressure. The end result is if you have the pedal to the floor, but are only have the cable pulled in a tiny bit (to make the trans shift at low RPM's) the fluid pressure that applies the clutches inside the trans might not be enough to hold the torque, leading to slippage and fried trannies.