6L80 max line pressures?

[mJolnir]

when do i want to increase max line pressure?
what is the difference between 'max pressure' and 'Max pressure B'?

I did a nitrous pass on the camaro, it went 11.2@123 mph, since im so close i would like to get a 10.9 but not at the expense of braking the transmission so i just want to make sure im set safely for the power its pushing when on the bottle (524 whp 555 lb-ft)

here is the tune in case there is something i should fix
camaro 2010 tcc slip.hpt

[Joshtuning]

what mods does your car consist of ?

[5FDP]

I'd play with your on-coming pressure presets before you start adding more line pressure to the transmission.

The 6L80e takes well to mildly changing the on-coming pressure presets for quicker/firmer shifts. I'd only suggest changing geras 1-4 as 5th and 6th are overdrives and don't really need it.

[mJolnir]

Hello, my mods are intake, headers, exhaust, tsp vvt stage 1 cam with supporting mods, circle D 3200 rpm stall converter and zex wet 125 hp shot, the car makes 425 whp N/A and 524 who on the bottle.

What i did with the transmission tune was, on coming presets for sport mode, turned up base shift pressure for sport mode, decreased base upshift time, and increased the tcc pressure to get rid of some unwanted slip, moved shift points to 6200 rpm to take advantage of the cams power curve, but then had to take 1-2 shift down so it wouldn't hit the limiter when on the bottle.

Last night i went to the track and got a 12.0 n/a and a 11.1 on the bottle, the thing is even if the track times are consistent, the shift feel isn't consistent when on the bottle, on my last nitrous pass of the night i was running with low bottle pressure but got a 1.56 60ft time (previous best was 1.65) and it hit the limiter again on the 1-2 shift, so i need to take it down a bit more, but what made me open this thread is that 3-4 shift sometimes feel good and crisp, sometimes it feels sloppy and some other times it feels like it has a bit of a flare, all of this only happens when on the bottle, that makes me think that there is room for improvement on the tune.

[Joshtuning]

do you have a log of your run ?

[realcanuk]

Make sure the trans is overfilled by 1 quart.

[mJolnir]

do you have a log of your run ?

No logs yet, but in two weeks is the last track opening of the year, i can get a couple of passes logged, any pids in particular i should pay close attention to?

[mJolnir]

Ok, just back from the track, got a best time of 11.9 N/A.
Overfilled the trans fluid by 1/2 quart per realcanuk's recommendation, transmission behavior didn't change that i could notice.
Only made 1 nitrous pass and got it logged, didnt do any more passes because of the knock.
the 3-4 shift felt weird again, it felt like the car hit a limiter right before the change, but the limiter is set higher, aside from that while N/A it felt pretty good and consistent.
what would you change for longevity if the trans in the tune?

trackflex nitrous1.hpl
camaro 2010 E85-4 track NA.hpt

[mJolnir]

ok, im opening a new thread for the 3-4 hesitation, the original questions were never answered, when is it needed to raise "Max line pressure"?

[realcanuk]

ok, im opening a new thread for the 3-4 hesitation, the original questions were never answered, when is it needed to raise "Max line pressure"?

I would try raising oncoming preset pressure like 50% and see how it shifts. Don't forget to reset the adapts after changes.

[mJolnir]

I would try raising oncoming preset pressure like 50% and see how it shifts. Don't forget to reset the adapts after changes.

50% from stock, or 50% from what i have?
the shifts are pretty fast, logged shift times are:
0.13s 1-2 shift
0.08s 2-3 shift
0.10s 3-4 shift

i set the pressets per this thread recomendations:
http://www.hptuners.com/forum/showth...highlight=6L80

[realcanuk]

In that thread he has them set much higher. I wouldn't necessarily go that high but I have mine set much higher than yours. Not at computer right now so not sure exact numbers, I would increase then 50 % from where you have then and work from there if it's helping.

[mJolnir]

In that thread he has them set much higher. I wouldn't necessarily go that high but I have mine set much higher than yours. Not at computer right now so not sure exact numbers, I would increase then 50 % from where you have then and work from there if it's helping.

i left the pressure presets for D stock, and i am using the special mode for S mode on the transmission, for S mode the presets are set to 200, 950, 1500, with that setting it already chirps the tires, on the logged file, the chart vs time for speed you can see spikes on the 1-2 and 2-3 shifts meaning they are pretty agressive, but the 3-4 is not like that, should i still give it more pressure on the presets fot the 3-4 shift?

[realcanuk]

i left the pressure presets for D stock, and i am using the special mode for S mode on the transmission, for S mode the presets are set to 200, 950, 1500, with that setting it already chirps the tires, on the logged file, the chart vs time for speed you can see spikes on the 1-2 and 2-3 shifts meaning they are pretty agressive, but the 3-4 is not like that, should i still give it more pressure on the presets fot the 3-4 shift?

I just looked in more detail. Missed that you had raised then in special mode. The log shows that little stumble on the 3-4 shift. I don't really see anything in the tune that sticks out to cause that. I would try bumping the max line pressure up and see if it helps. I run mine much higher than yours, but my trans is not stock, and I am not sure how high is good on a stock trans. My max line pressure is at 255, and max pressure is at 130, and those numbers work well for me.
The other thing I might try is raising the spark minimum-tqmgt table, so that it doesn't pull so much timing on the shift. Yours allows as much as -20. I like to run it so that the most it can pull is 10 degrees from where my timing would be. For me that is set to 5 degrees.

If that doesn't help, I would start to think maybe it a mechanical issue.

[mJolnir]

I just looked in more detail. Missed that you had raised then in special mode. The log shows that little stumble on the 3-4 shift. I don't really see anything in the tune that sticks out to cause that. I would try bumping the max line pressure up and see if it helps. I run mine much higher than yours, but my trans is not stock, and I am not sure how high is good on a stock trans. My max line pressure is at 255, and max pressure is at 130, and those numbers work well for me.
The other thing I might try is raising the spark minimum-tqmgt table, so that it doesn't pull so much timing on the shift. Yours allows as much as -20. I like to run it so that the most it can pull is 10 degrees from where my timing would be. For me that is set to 5 degrees.

If that doesn't help, I would start to think maybe it a mechanical issue.

i left most of the tq management on to protect the transmission, would decreasing the minimum-tqmgt table make it harsher for the tranny?

[realcanuk]

i left most of the tq management on to protect the transmission, would decreasing the minimum-tqmgt table make it harsher for the tranny?

I don't find it harsher by feel. I guess pulling 10 degrees instead of 20 (for example) means a little more power to it, but mines been that way for a long time with no issues.

[HeavyChevy305]

i left most of the tq management on to protect the transmission, would decreasing the minimum-tqmgt table make it harsher for the tranny?

I'd zero out the spark minimum tqmgt table and do a trans adapt fast learn.

After making some irrelevant changes to my tune, my 3/4 shift started randomly hesitating as you're describing. I completed a trans adapt fast learn and it went away completely. I'm on a 150 shot for what its worth...

[lt1z350]

I build these transmissions for a living and have seen a code set max line and the customer keep driving it till it blows the snap ring out of the drum. It can shear the lugs right off so be very careful in how high you go on these. I am seeing it more and more as some in trucks get high miles the pump starts to wear it sees a slip sets max line and customer now thinks it is ok as shifts are crisp again and just rips it apart. Better to remove torque management settings on the shift and work with shift time settings I have found doing my ats with the smaller 6l45e which is the same just smaller parts. Acts the same to tuning from the trucks and camaros I have done too. They already run an a ton of pressure it is the computer that is constantly pulling it back just have to stop that and not worry on increasing over all so much. Also I run them with adapts off so stays consistent to what I am setting.