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2-3 shift again

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Old 06-14-2016, 09:51 PM
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OK good. Your original pressure numbers were so low I wondered if you really were testing at WOT.
Personally, I set my WOT shift MPH to correspond to about 6000 RPM. I then only need to change my WOT shift RPM at the track (typically between 6500 and 7200) to experiment.
It is also recommended to set the Part Throttle Shift table's 100% value to the same as the WOT value.

In short, the advice to lower your WOT Shift MPH by about 10% and your WOT Shift RPM by maybe 200 seems about right.
Old 06-14-2016, 10:10 PM
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Thanks mrvedit. So are you saying that you are able to set your wot mph properly for 6000rpm and don't have to adjust it to a shift rpm of around 7200rpm. Wasn't aware you could have large of a spread. I do not have my part throttle tables matched up to my full throttle tables at this time. I did some time ago but again RPM gave me some help and they were changed to be different from the wot tables. I figured they were much better at trans tuning than I am so I thought it would be ok. It does work well at least with my NA tune. Hoping it will also work with my N20 tune. Still have lots to learn.
Old 06-14-2016, 10:31 PM
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Yes, you can have that wide a spread - e.g. the WOT MPH might be 78, but the shift doesn't occur until 92 MPH when the WOT RPM is finally reached.
I read that some people tried setting the WOT MPH to Zero, but that caused problems.
People have also reported minor quirkiness when the WOT value didn't agree with the Partial table at 100%. I set the 94% and 100% values to agree with the WOT value and set the "Full Throttle Enable" value to 96% as the TPS sometimes only reads 98% at WOT.
Old 06-14-2016, 10:34 PM
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I just learned something. Thank you
Old 06-14-2016, 10:58 PM
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You are welcome; I still have a lot to learn too.

Glad to be posting and trying to help again - I was busy for a few weeks with a "24 Hours of Lemons" car race in Colorado - first getting my M3 ready for some track time, flying to Colorado and getting the race car ready, then three days of practice and racing, then a few days of vacation with family and finally getting caught up with work.

Last edited by mrvedit; 06-26-2016 at 05:39 PM.
Old 06-25-2016, 10:07 PM
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Finally got a chance to get to the track today. Not the results I was hoping for. I had made a number of changes to my nitrous tune. I adjusted my shift rpm from 6450 down to 6200. I adjusted my shift mph from 81 down to 70mph. Changed my shift times for normal to .125 and for performance back to stock at 0.0 seconds. Also changed my shift pressure performance table back to stock which is 90 in all table boxes. Although I didn't hit the rev limiter the second to third shift still didn't happen until 6787rpm. So I then dropped my shift rpm down to 6000rpm and my shift mph down to 68 mph and made another pass. The shift took place at 6722rpm. Only a difference of 65 rpm. Not what I was looking for. I once again don't understand why this isn't working as expected. I have attached both log files and my tune files. I have logged many of the transmission related items. It also looks like I have a lot of TCC slip but not sure if it is ok or not. Please HELP!!!
Old 06-26-2016, 05:45 PM
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While your 1-2 shift WOT MPH is at 69 mph, your 2-3 shift WOT MPH is 109 mph!
Your 1-2 shift WOT RPM is 6450, your 2-3 shift WOT RPM is 6000.

Therefore I think you got your table rows mixed up a bit.
I suspect your 1-2 shift is when 6450 RPM is reached, but your 2-3 shift won't take place until 109 MPH is reached.

Last edited by mrvedit; 06-26-2016 at 05:59 PM.
Old 06-26-2016, 09:30 PM
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mrvedit,

I'm trying to figure out where the 109mph comes from. My 1-2 shift from my WOT tables is set for 6450rpm and 43mph. My 2-3 shift is set to happen at 6200rpm and 70 mph. The 1-2 shift happens pretty close. The 2-3 shift didnt happen until 6787 at 88mph.

However, after trying to figure out what you were trying to tell me I found what I did wrong. After all my adjusting and reviewing for the last 3 weeks I made a stupid rookie mistake. I didn't adjust my 3-2 downshift mph down. It's still set higher than my upshift mph. Stupid mistake. Now unfortunately I have to wait two more weeks to see if that fixes my issue.
Old 07-09-2016, 10:40 PM
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I was able to get out to the track with the car today. Finally, we have success. My first pass my 1-2 shift rpm was a little high and my 2-3 shift was dead on but set lower than I wanted ideally. For the second pass I lowered my 1-2 shift rpm by 100 rpm and raised my 2-3 shift rpm by 100rpm. It responded perfectly. I'm really happy to get this work. The track I was at did not have ideal conditions for traction. The starting line was hot and slimy and got worse as the day went on. I did get one great launch and got an all time best 60' time. I have a tune that I can work with finally.

Appreciate all the help. Thank you!!!
Old 07-10-2016, 10:21 PM
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Good to hear that you got it all figured out now.
Thank you for posting the update.
Good luck with future track sesssions.



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