rcdash

iTrader: (18)

Those are good times - I was hoping it was just your tires slipping and not something in your drivetrain.

Why are you at a 113 mph trap with a Greddy kit and a built motor? How much boost? You just taking it easy on the 5AT?

Has it always been like this? It looks like the torque converter is not locking up to me. That might explain your trap if you're supposed to be putting down something in the 500 whp range. Does it hold on the dyno?

MardiGrasMax

iTrader: (8)

Thanks for your input, I appreciate it! The 113 trap was due to hitting the rev limiter in 2nd, she has trapped 118. Boost is 14psi on pump 93. I am slowly preparing to turn it up to 16 or 18.... She has never been on a dyno. I tune her on the street myself. If I do a tuning pull in 4th on the highway it holds just fine, its just slips duting the shift. The 3/4 has allways done that, I dont do a 3/4 WOT shift very often, most street fun is over in the top of 3rd. I do have a spare stock converter too, maybe if the the transgo does not do the trick the i can try that. Good thing I love to work on my car

Does Uprev have the ability to control converter lock up like some of the domestic tuners do?

rcdash

iTrader: (18)

No UpRev has nothing for TC lock up. Even if it's not locked up the fluid coupling should be so tight that you still gain speed even while rpms stay constant (as the driveshaft spins up to match the speed of the engine). Maybe something is broken in there? Andre at Edge Racing has provided me a couple good converters. Just send him your core and some specs on your car and what kind of stall you are looking for (looser makes for a better launch but is more inefficient at speed). I chose 3k rpms because he would not go any lower. My first GTM t/c was a little mushy around town - stalled about 300-400 rpms higher.

djamps

iTrader: (1)

Actually you do have TC control in Uprev. You ABSOLUTELY have to make sure you're load scaler puts you at 100% any time you're under load -- this is what the TC looks for. By default if you don't change anything, you'll end up at 70% at full boost and the TC never locks up, tranny kaboom.

rcdash

iTrader: (18)

Based on an explanation from Jared, my understanding is that "calculated load" is just based on MAF output and my stock MAF max's out early. My calculated load is 100% even on part throttle. It's the reason us 5AT guys cannot get rid of the MAF. Well actually Haltech can generate a fake MAF signal now...

MardiGrasMax

iTrader: (8)

Interesting... I use the UTEC in Speed Density mode, but the UTEC still modifies the MAF voltage going to the ECU all the time. My MAF logs show the modified MAF signal from the UTEC to the ECU peaks and holds at ~4.1v, Actual is of course 5v to the UTEC, but the ECU never sees it.

Could this 4.1v MAF signal be causing the torque converter to not lock up fully like it would at a higher load level with a higher MAF voltage? But wouldnt it show up in all my shifts, not just the 3-4?

Vince@R/TTuning

iTrader: (7)

Calculated load is based of of base fuel schedule and RPM. There is a table in Rom editor that u can modify to get a more accurate calculated load. Although I have messed with it dozens of times It hasnt made too much of a difference. I have cars come in that are at 100 calc load at half throttle and some that never hit 100 percent calc load and it doesn't seem to adversely affect it either way.

djamps

iTrader: (1)

It's important to take into consideration on a 5AT. 'Close enough' might be well enough in most cases... but if it's too far off, the TC will eventually be destroyed, 5AT overheat, ect ect..this is coming both from the manual, Jared himself and my local tuner.

Vince@R/TTuning

iTrader: (7)

^^^ I understand that....Let me rephrase..I was actually speaking towards rcdash when he said it was at 100% calc load at half throttle, I have had several vehicles come in like that and it doesnt seem to adversly affect them. On all the Automatic cars I always trim in the calculated load so at full throttle its at 100% the whole time...which usually takes making the base full schedule values lower at higher rpms as torque drops off.

rcdash

iTrader: (18)

^ and the base fuel schedule is based off MAF output, correct? It's the reason I couldn't originally get rid of my MAF for my 5AT. A few psi above atm and no issues with overloading that stock MAF. Maybe Jared fixed my tables when I got my original reflash. I sent him my Haltech maps and dyno so he knew what I was up to.


MardiGrasMax, I would log the calculated load in Cipher and make sure it reads 100%!!! Very important for crisp shifts. This affects one of the main clutches in the transmission itself, not the TC (as I understand it).

CLyons0203

iTrader: (1)

3-4th shift fix:

http://g35driver.com/forums/tuner-dy...-w-osiris.html

djamps

iTrader: (1)

@vince... got it, thanks... I wasn't clear on what you said.

@rcdash... yes, the MAF is a big part in the fuel sched. calc.

MardiGrasMax

iTrader: (8)

Would you guys think that a MAF voltage of only 4.1v but with 100% TPS and near redline RPM be enough to call for TC lock up in my situation?

Whats the highest MAF voltage the NA cars normally see?

Vince@R/TTuning

iTrader: (7)

typically tune good flowing N/A set ups hit around 4.5-4.7 Volts at redline...

kacz07

iTrader: (15)

Is this power dependent? What other factors would cause higher voltage on an NA setup?

Vince@R/TTuning

iTrader: (7)

^^^ In theory... Making more power would cause more air to be drawn through which would cause a higher voltage. The more air the motor draws the higher the voltage... higher voltage isn't really a bad thing until you run out of it...

MardiGrasMax

iTrader: (8)

So I datalogged using an OBDII code tool I have a and my ECU load (LOAD_PCT) peaks at 83.1%. Would this cause the 3-4 shift issue?

CustomGsedan

no info specific to the fix (as of now anyway)... just that Derek's 3-4 is now better - but nothing about how it was fixed...

jmicaelk

iTrader: (19)

Are there any updates about this or ??
I will be driving a 5AT after I move, so this would be great and let me boost

djamps

iTrader: (1)

That's a serious problem. It should be at 100% anywhere past half throttle IMO. At 83% the TC won't lock up, you'll have slow shifts, and an otherwise fried tranny.