Trans. Tuning Shift points, pressure, shift time..

[RedZMonte]

Ok so i asked on C-GP and got a answer i wasnt searching for.. Is there a general consensus of what settings should be for reliable but good shifts on the 4T65-E? I have looked at multiple DHP bins and they are all different... this is going on a 2004 Monte SS L36. Any of you guys have suggestions for a good starting point? I don't want to just start changing shyt without knowing what is to much and what is not enough you know?

thanks,
S

[chri0029]

Did you ever get an answer (PM maybe)?

Or did you find some good shift points yourself? Or maybe you fried your trans while trying??

I'm looking for the same info, or at least somewhere to start. I see stuff all over the board as well.

[3400-95-Modified]

I've found that shift points are really more of a personal feel thing rather than a general deal... Best is to start with factory and just drive the car as you would and log as much as often... and when you feel something you don't like, aka bog and should shift down... Mark that in a way with a pause in a scan right after that condition... Then you can evaluate the condition, TP, RPM, mph, Load and so on, and come up with a better shift point.

As far as shift pressure and what not... I don't have those controls in my ecm and I use the vac modulator for that, but I once again go off feel... you want a decently firm shift most of the time but not whiplash firm... since that will strain your drive-line in other areas, so once again you can only dial that in with lots of logs and feel for the car.

Everyone' shift table will differ since every car is setup different so its really hard to nail down a good shift configuration that most can use.

[chri0029]

Yea, to complicate it more, I'm trying to tune shift points vs. my KR.

[3400-95-Modified]

Are you trying to adjust shift points to compensate/remove KR?

Sounds like you should be attacking the spark table first to get rid of that, then work on the shift points to your liking, and then either put the spark table back to see if the KR is still there, Or begin a fine tuned spark tune now that your shifting the way you want to.

[chri0029]

No, I'm in general just experimenting with HPT and my spark advance and other stuff. It's so damn cold outside that I figure I have some wiggle-room in the spark table. I was doing a log this morning with +5 additional advance (across the board) and was getting high KR while going up a huge hill. Plus, after looking at the log, it seems most of my KR is in 4th gear rather than when I'm in 3rd in general. I figure it's load-related so I can play with shift points to a certain extent to make-up for that. The rest will be getting enough log information to intelligently remap the spark table rather than just a 'blanket' 5 degree advance.

I'm also playing around with the AFR as well in combo with the spark since I believe we use about 5-10% ethanol in MI in the winter. So I'm shooting for ~14.3 from what I'm reading but can only seem to do this in OL with my stock NB since it always wants to go back to 14.7 (or at least what it thinks).

Anyway ... sorry to get WAY off-track of this thread. Too bad you weren't in S.E. MI since I need a mentor to compare notes with (in addition to what I read on this site).

[chri0029]

I really don't mean to get too far off the trans thread topic, but 3400-mod, do you run a 180 degree stat in your car to keep temps down to reduce the KR?

I tried doing a search for "thermostat' on this site to see the theories about 180 vs 195 degree engine temps in general but got an error in doing this.

[3400-95-Modified]

yeah I run a 180, but not to reduce KR... I do that simply to keep the engine temp just a bit lower since 195 is quite high.

If you have KR only in 4th, then hit the table in that area only... You wont gain a bunch from adding a but load of timing at low RPM high Load... The gain is more in the area of low load low RPM more like crusing, you can gain better MPG by optimizing that spark advance... and obviously as well as heavy load high RPM you can gain power by dialing in that close to its limit.

[chri0029]

Thanks for the reply.

I took this thread over to the following so I don't piss off the moderators too much (since we're on a trans shifting thread):

http://60degreev6.com/forum/showthread.php/47333-Help-Knock-LTFT-and-low-mpg-(stock-cal)-3400