line pressure

[ImpBluSS]

I'm having a little problem getting the trans. to shift quickly and firmly on the bottle. It's an rpm trans. so I called them and they told me to check the line pressure and that I should have 240-250psi at WOT. I'm only seeing 200. My question is how do I increase the line pressure using hptuners. I've increased the upper end of the shift pressure table 15psi and am not seeing any increase in line pressure. This is based on the stock settings as a starting point. I was trying to be cautious because the tranny has a trans. go shift kit. Have I just not gone far enough yet?

[ImpBluSS]

Ok, so I spoke to RPM again and they had me disconnect the case plug connection by the cooler lines in order to check the line pressure without any input from the computer. It had 230psi and so they said it was fine and had to be in the tune. Next I went to upping the psi values in the shift pressure tables with not much success. Then I went and copied and pasted the tables ed wright had originally used when he tuned it for the stock trans. and got about 10psi. Still wondering which tables directly affect line pressure. Any input would be greatly appreciated...

[02c5z06]

Im interseted in what you can discover as I'm having the same issue with my RPM level 5 trans with hardened output shaft with a Magnacharger 122HH setup making about 500 rwhp on a '06 TBSS. Both the 1-2 shift and 2-3 shifts bang off the limiter at WOT until I let off the gas. The trans shifted perfectly under WOT when new but now seems to not have enough pressure. It still shifts very well during part throttle shifts. My trans only has about 15,000 miles on it and also has a deep trans pan, cooler, Vig converter. I waas going to increase the base shift pressures as you attempted but now I'm skeptical if it will make any difference. Please post your resolution should you have any success and I will do the same. Hopefully someone will help us out if we don't have any luck.

[MNR-0]

Theres not much you can do in the trans - yet to some it is more complicated to tune than the engine.

To command the fastest shifts:

zero out torque management
zero out shift adaption times
raise base pressures

Now there is no magic numbe to raise them to because its all relative to the trans. Some like more, some less.

I usually run 80-90 from 320ft-lbs on, ramping down to 0 at 60ft-lbs

That commands 100% line pressure - whatever that is. Max for WOT and less for part throttle - unless you like kneck snapping, diff breaking shifts.

If the base pressure table gives no joy, then you have to play with the force motor table. If lowering values there gives no joy, your solution lies elsewhere.

[gman4dx266]

What MNR said is accurate. If you fiddle your tune around all day long and see no gains, you've got another thing coming. If your gear change pressure tables have astronomically high numbers in it all over, then you're adjusting wrong and need to work a tiny bit with your force motor table. the higher the number in that force motor table, the softer the shift. I think the max is 1245, which is a FULL pressure bleed off [no pressure]. 0 is max pressure. Find the row/column where you need to get some pressure (assuming you've got a decent 1>2,2>3,3>4 table thats not unreasonably high) and start taking some numbers off whats in you're table. I had to do this a tiny bit on my 4L80, since my table was maxing out @ 96 about half way through. I may actually try what MNR saiid about running 80 to 90 from 320 and then narrowing down to 0 @ 60. I cant leave well enough alone lol

[ImpBluSS]

I spoke with someone that was having similar issues and they told me it had to do with the force motor table also. I've got new settings to try and I'll post up whether I saw the desired results. Thanks for the input.

[02c5z06]

Have you checked your trans fluid level. Mine was just a little bit low and after adding about a pint it now shifts perfectly again at WOT. It would shift fine the rest of the time but only during WOT runs would it not complete the 1-2 or 2-3 shift without letting off the gas momentarily. I simply overlooked the obvious and then checked the fluid level, added the necessary Dexron VI and all is well again. I'm making ~500 RWHP on a RPM trans with over 15,000 miles on it. Look into your trans fluid level if you haven't already.

[custosonlinux]

Hi,
I know this thread is four years old, but I'm having the same problems.
What are your new settings?