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Does the tranny shift at MPH or RPM in OD?

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Old 01-24-2004, 06:03 PM
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Talking Does the tranny shift at MPH or RPM in OD?

I'm confused. I'm getting a shift of 5705@38mph then a shift at 6189rpm @ 76mph.

Each shift is dropping the (shift extension?) to 4745/4800 respectively. I let off the gas at 103mph @5424rpm.

Is my efilive off or something?? We verified the speedo was calibrated to the virtual dash at 40mph it was spot on.

Is 103mph@5424rpm sound right for an A4 with 3.42 gears?

I'm wondering if my efilive v6.3 is off or something. I was told the car was calibrated to shift 1st@6200, 2/3/4 @ 6400 and redline at 6600.

Are there other factors that dictate the shift points, or perhaps my efilive is twacked out. TPS was 100%, duty cycle was 102% on the 76mph shift at 6189 rpm's. (102%???)

Does the tranny shift by mph or have various settings? The motor was at 180F ECT (160 thermo), IAT = 68F , LTFT (both) About 9.4% . No knock retard was present during the efilive logs except at 10% TPS low RPM where my paceSUCKER LT's are banging the Kmember.

Would someone mind explaining exactly how the ECU controls shifting? This car is ls1edit tuned, but perhaps i just dont understand the various conditions that can cause shiftpoints to be lower than programmed?

MAX RPM logged on a 6mph roll run to 103mph was 6189. I would have figured it would have shifted higher than 5705 the first time. Is it possible the RPM function in efilive v6.3 is screwed?

Sorry i'm a newb and playing with the new toy (Efilive) i'm trying to learn more about this car and how it works. I do VW tuning, so i'm not retarded , just never have done automatics so i'm n00b in that aspect.
Old 01-24-2004, 06:39 PM
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WOT upshifts are determined by both RPM and MPH values. Both values must be met before the upshift will occur, and both parameters are avalibile to tune/adjust in Edit, however RPM changes seem to have less effect on the actual upshift than MPH settings do. In theroy, if you set your RPM to 6200, it should have to reach 6200rpm reguardless of MPH before the upshift, but that isn't always the case in reality.

I found that for my PCM it took a number of attempts with tuning both values to get what I wanted, and MPH changes had a greater effect than the RPM changes did. I was aiming for 6300rpm upshifts, and I had to do 6200rpm for RPM settings and I beleive I used 43mph & 83mph for the 1-2 & 2-3 shifts respectively to achive a real time 6300-6400rpm upshift. That was/is with a SY3500 stall and stock 3.23 gears with stock tire size/height.

Now, remember that your testing data is useless if you had any (other than minor) wheel spin when launching, or you went from a slow roll. I found this out the hard way testing myself. When going from a dead stop with (near) full traction, I'll get my 63-6400rpm upshift, but if I get major wheel spin, it will shift as early as 58-5900rpm on occasion. Going from a 20-25mph roll will get me 61-6200rpm upshifts, and going from a 30-35mph roll (that's as fast as I can be going to still get a downshift to 1st) it'll shift at 6000rpm.

Also, your trans fluid level has to be basically dead on full for the proper upshifts. Low or high fluid level can also effect shift points.

Hope that helps.
Old 01-24-2004, 07:17 PM
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damn so its not so clear cut at all. Thanks for explaining. i'll have to digest this. Sounds like its time i get a copy of edit and tweak it to my liking huh? I mean if its not so plug n play, it would be a burden to ask my tuner to make changes so often as conditions play.


Lemme ask you this (since you know a good bit). Would it make sense for me to get edit and adjust the paramted of my car for strip/street.

Like could i squeeze out alot more MPG by altering the shifting for 90% CITY (35mph max) and 10% freeway, then upload a new program for strip use?

Due to traffic tickets, i doubt i'll be maximizing my tune for strip on the streets, i dont care to goto jail so my runs to 100mph will be very very few.

Can the ssf3500/transgo be tuned to provide a much higher degree of mpg at street driving by altering the shift points and lockups given the assumption i won't be driving mad on the streets? Then modify the pcm when i go to the track to optimize for drag racing?

I got 33miles to 1/4 tank of gas which is why i'm asking 120miles to 14 gallons. about 20 miles of that was on the freeway. Seems ridiculously low and i suspect its cause im always between 2500-3000rpm crusing from 0-40mph between all the stoplights?

whatcha think?
Old 01-24-2004, 07:40 PM
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Lemme ask you this (since you know a good bit). Would it make sense for me to get edit and adjust the paramted of my car for strip/street.
Truthfully, if your only reason for getting Edit is to change shift points, it's probably not worth the expense of $550 since you've already paid for a tune. Most tuners will make changes for stuff like shift points for little or no extra money once you've paid for the first tune. I know MTI used to make all my shift point changes for free back before I had my own Edit. Now, if the money is no object to you, and/or you intend to do and feel comfortable doing further tuning on your own, go for it!

Like could i squeeze out alot more MPG by altering the shifting for 90% CITY (35mph max) and 10% freeway, then upload a new program for strip use?.....Can the ssf3500/transgo be tuned to provide a much higher degree of mpg at street driving by altering the shift points and lockups given the assumption i won't be driving mad on the streets? Then modify the pcm when i go to the track to optimize for drag racing?....I got 33miles to 1/4 tank of gas which is why i'm asking 120miles to 14 gallons. about 20 miles of that was on the freeway. Seems ridiculously low and i suspect its cause im always between 2500-3000rpm crusing from 0-40mph between all the stoplights?
You can make as many files and changes as you want. That's the great thing about having your own Edit. But I don't think that making adjustments to your low rpm (cruising) shift points will make much difference in your MPG. You could change the converter lock-up points, but it's not going to give you a drastic increase in low speed stop-and-go MPG even with that. It's just the nature of a higher stall TC to kill some city mileage, due to that stop and go driving, now with higer rpms because of the 'verter.
Old 01-24-2004, 08:14 PM
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you dont think like locking the verter at 10-15mph and during shifts would help with mpg in the city? Only reason i paid the tuner to tune the car is because im new to gm ecu's. I do VW shiz all the time. Why bang your head reinventing the wheel when a pro-tuner can knock out a good tune in a short time and well it was part of the install package. I've got the wideband (2 of them actually) and extensive knowledge of tuning cars (boosted mostly) but transmissions are new. So i figured get a great baseline tune from the tuner, then take it from there.

I guess i didn't realize that my mpg would be so hurt by city driving with the verter. Nobody mentioned that. Like 120 miles to 14 gallons of gas. I might as well drive the vw since it gets better gas mileage and is just as fast from 0-40mph while not laying drag lol

Thanks for your insight, you've given me some things to chew on.. I'll go bug my tuner for now. Maybe i can get 3 people to go in on a copy of edit lol.

i totally think my tuner is great and all , but being a tuner myself, its easier to transition to a new platform and have a great base tune to work with. Then take it from there. I actually enjoy driving the car not tuning them lol. im more a programmer, ask me how to change how the ecu functions, thats my spiel. Driving around with a wideband or dyno tuning, well that sucks.

oh well more gadgets to buy. i'll hold out for a bit and see what this year has to offer with competitors tuning products. Maybe something non-vin locked and good will come out




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