Help with tuning stock truck

[joecar]

Wow thanks so much,
Im reading this from another computer but im about to go get to work changing it on my labtop.

One question though, what is the diffrence between an upshift at WOT and a throttle kickdown?

And how do you guys read your saved data on efi live?
There is the stock setup that is good and I use the B dashpage, but there is only so much on there. And it seems like you can't change what shows on the B chart page, you can only put new gauges in?

Anyway I would have never even remotely known what was going on without yall helping me. Thanks again

You're welcome.

Throttle Kickdown: if the throttle hits/exceeds this, then the PCM commands a WOT downshift (see next sentence).

WOT downshift: when the throttle hits/exceeds Throttle Kickdown value, and VSS is below the WOT downshift MPH, a downshift is commanded regardless of the PT downshift table (PT = part throtle);

WOT upshift: when VSS hits the WOT upshift MPH, an upshift is commanded regardless of the PT upshift table;

If the WOT downshift MPH is above the WOT upshift MPH, and you bring the throttle to WOT, the tendancy is to not upshift.

If the Throttle Kickdown value is less than 100%, the tendancy is that this may override the PT upshift table (prevents upshift) and the PT downshift table (downshift doesn't match table)... i.e. the shift pattern will be "strange".

To change a gauge: you can right click on a dash gauge to change its properties (including the PID), and "Save As" using a new filename.

[joecar]

Alright I adjusted everthing and im ready to go log and test it out. I will post up the results once im done.

Thanks again

Post your updated tune so we can sanity check it.

[cmitchell17]

Ok ive taken my data.

The part throttle shifts feel really good.(they are not annoying and they feel solid and you know they are better for the life of the trans.)

First I notice in the log right before the 1-2nd shift pressure goes from 90psi to 45psi then back up to 85psi right before it shifts. What would command it to do this?

The WOT shifts feel the same, it feels like at high rpm it stops pulling hard then right when it shifts it like grabs and slowly pushes you foward then goes back down to around 3000 and bogs down in the high 2nd gear.
They just arnt quick.
So how can I fix this?

[cmitchell17]

What do you think about abuse mode and TM and things like that. Should I leave them a little decreased from stock especially since I have a stock trans?

I always here that the stock trans suposedly only last about 130K, I have 120K on my truck.

I dont believe that they could only last that long, especially with all the resrictive stock tuning. What do you think?

[joecar]

Ok ive taken my data.

The part throttle shifts feel really good.(they are not annoying and they feel solid and you know they are better for the life of the trans.)

First I notice in the log right before the 1-2nd shift pressure goes from 90psi to 45psi then back up to 85psi right before it shifts. What would command it to do this?

The WOT shifts feel the same, it feels like at high rpm it stops pulling hard then right when it shifts it like grabs and slowly pushes you foward then goes back down to around 3000 and bogs down in the high 2nd gear.
They just arnt quick.
So how can I fix this?

The PCM uses the shift pressure tables during a shift; but when not shifting the PCM uses some other [yet-undiscovered] running-in-gear pressure tables/calculation; why would these tables/calculations cause a pressure dip right before shifting is a good question...

I don't know, would the dip to 45 psi be related...?
I noticed in the log that the lastshift time seemed higher than expected.
I'll take another look later today.

Take more logs (include these pids: GEAR, TRQENG, TCCMODE... and remove some of the other pids to keep the channel count no greater than 24)...

[joecar]

What do you think about abuse mode and TM and things like that. Should I leave them a little decreased from stock especially since I have a stock trans?

I always here that the stock trans suposedly only last about 130K, I have 120K on my truck.

I dont believe that they could only last that long, especially with all the resrictive stock tuning. What do you think?

Torque Reduction helps in avoiding breakage of hard parts in the drivetrain; it (along with shift pressures and shift times) can be used to fine tune the shift feel, and still be within the "safe" envelope; a little decreased from stock is good since stock is very conservative... You can see when it kicks in by the momentary reduction in spark timing.

Abuse mode is used to prevent/reduce damage say when shifting from Park to in gear while throttle is being applied... I don't know if it kicks in at any other time/condition; it's like "idiot-proof" mode.

Some transmissions go longer than 130K, it all depends on several things:
- regular fluid/filter changes prolong life;
- driving habit (WOT ocassionally is ok; WOT all the time reduces life);
- fluid temperature (too high degrades the fluid properties, too low reduces lubing ability);
- how your trans. was put together (tolerances, part quality), some people get lucky, some get unlucky;
- maintaining the fluid level on the mark (or slightly above it).

[cmitchell17]

Ok I think I figured it out.
I took some more data and found that at WOT before it shifts the torque drops off to about 230ft.lbs. at about 5800rpms when it shifts.
So I guess the solution is to ramp up the pressure cruve right before 230ft.lbs. hoping that the pressure will increase during the shifts.

Is this supposed to happen? Stock at 230ft.lbs. psi is only at 50psi?
Sorry if you use metric.

So is this causing my sloppy shifts.

And I dont see why with my timing at around 26-28degrees from the stock of 16 why I havent seen in increase is performance? I also leaned out the WOT AFR too. I havent noticed a diffrence. Mabey it is just me and I dont notice it, but other people who have gotten custom tunes are all amazed at the diffrence in performance from the stock tuning.

Another thing am I mabey shifting at too high and rpm for the pressures? Like it is going to high an rpm and torque is dropping off so much it dosent think there is much power about to go through the trans on the shift?


I hope I can get it fixed and get it shifting good
here is some data that I hope will help.

[joecar]

Yes, if TRQENG drops off, you will move further left on the shift pressure tables... good deduction...

I'll look at your new files later tonite...

Are you running SD...?
Is your VE dialed in (BENs == 1.00)...?
Check your AFR.
Check your spark advance.

[joecar]

Ok... I see the drop in TRQENG from 324 ftlb to 216 ftlb... and I'm wondering why...?

[cmitchell17]

Ok I havent even touched my VE tabels, but why should I if I have a completely stock motor?
I would think it would be better to just leave them alone.

I have no wideband to verify my AFR, but im commanding about 12.4-12.6 at WOT. My timing stays 25-28 degrees at WOT with no KR.

And I dont think im running SD I havent changed any of that.
Is it better to run SD? What is better about it?
Im guessing the MAP sensor is more accurate under AE becuase ive heard that MAF sensors give and inaccurate reading with rapid changes in ariflow.
I also used to tune my 95 truck with tbi on it, and I have not yet figured MAP out not less MAF out.