New Converter, what to change in tune????

[BlackGMC]

I just got my converter installed today!!! It is a 2800 Performabuilt 9.5 converter... The converter is pretty loose, I am going to start working on my tune tomorrow hopefully.... Just trying to see what the rest of you guys had to do...

The Good:
The truck freaking moves really good now!!!! IMO and Built408's it stalls higher than 2800... Part throttle it stays in the power band!!! 4th gear lockup is nice and solid, TC stays locked with the cruise control on. Easily lights up the tires from a stop, which it never did before....

The Bad:
The 1->2 shift got really alot softer... Before it would give a pretty good jolt on the 1->2 shift at Part Throttle and WOT... At WOT I hit the fuel cutoff right before the shift... Idle needs some work cause it dies sometimes when coming to a stop, and it surges a little bit more...

These are a few of things that I am thinking about changing...

I lowered my 1->2 tranny pressures lower than stock before to keep the shift from not being so harsh, so I am going to put it back to stock and see how it feels, maybe raise some of the part throttle areas in all the gears... I am thinking the reason I hit the fuel cutoff was because of the lower tranny pressure, but I will raise it up some, just to be safe... I will redo the RAF tables (desired airflow, throttle cracker and follower) to help with the idle problem.... Also I plan on decreasing the idle over speed spark table and increase the idle underspeed spark table to get the idle a little bit more stable... IMO the decreased size and weight of the new converter the engine is alot more sensitive and reacts quicker... I might also lower the TC lockup speeds in 3rd and 4th so I am not cruising around with the TC unlocked at low speed...


Anyone think of some other things I need to change or log?

[joecar]

To soften the shift a little, keep the 1->2 pressure the same, and instead increase 1->2 Torque Reduction...

The idea behind this is to prevent slippage and instead pull some ignition timing for about 0.2 seconds to soften the shift.

[SRT10KLLR]

After my high stall I had the same issues. Before it would chirp the tires real good at very light throttle now I really have to get into it to just get a scratch. I also am getting some shuttering when I am cruising at about 40-50 MPH and start to give is some gas. In order to avoid that I need to give it a lot of gas and then it scoots pretty good.

What can be done in the tune to remove this problem?

[LS1FREEK]

After my high stall I had the same issues. Before it would chirp the tires real good at very light throttle now I really have to get into it to just get a scratch. I also am getting some shuttering when I am cruising at about 40-50 MPH and start to give is some gas. In order to avoid that I need to give it a lot of gas and then it scoots pretty good.

What can be done in the tune to remove this problem?

my truck shutters as well around 50, its like the converter wants to lock but cant decide... I could use some help as well.

[joecar]

Post your tunes... there has to be at least several mph difference between apply speed and release speed to prevent hunting.

[SRT10KLLR]

My tune in regards to the TCC lockup is completely stock.

Here is the TCC Apply Speeds for 4th gear:

LABELS Gear mode
TPS % {link: SAE.TP} Normal Performance Hot Cruise
0.00 37.500000 54.000000 59.500000 37.500000
6.25 37.500000 54.000000 59.500000 37.500000
12.50 37.500000 54.000000 59.500000 37.500000
18.75 37.500000 54.000000 59.500000 37.500000
25.00 41.500000 54.000000 59.500000 41.000000
31.25 47.000000 54.000000 59.500000 48.500000
37.50 52.500000 54.000000 59.500000 56.000000
43.75 58.500000 54.000000 61.000000 63.500000
50.00 75.000000 54.000000 63.000000 75.000000
56.25 75.000000 54.000000 66.500000 75.000000
62.50 75.000000 57.000000 72.000000 75.000000
68.75 75.000000 70.000000 77.500000 75.000000
75.00 75.000000 70.000000 255.000000 75.000000
81.25 75.000000 70.000000 255.000000 75.000000
87.50 75.000000 70.000000 255.000000 75.000000
93.75 75.000000 70.000000 255.000000 75.000000
100.00 75.000000 70.000000 255.000000 75.000000

and here are the TCC Release Speeds for 4th

LABELS Gear mode
TPS % {link: SAE.TP} Normal Performance Hot Cruise
0.00 35.500000 52.000000 59.000000 35.500000
6.25 35.500000 52.000000 59.000000 35.500000
12.50 35.500000 52.000000 59.000000 35.500000
18.75 35.500000 52.000000 59.000000 35.500000
25.00 35.500000 52.000000 59.000000 35.500000
31.25 38.000000 52.000000 59.000000 38.000000
37.50 43.500000 52.000000 59.000000 43.500000
43.75 48.500000 52.000000 60.500000 48.500000
50.00 54.000000 52.000000 62.500000 54.000000
56.25 59.500000 53.000000 66.000000 59.500000
62.50 68.500000 57.000000 71.500000 68.500000
68.75 72.500000 70.000000 77.000000 72.500000
75.00 72.500000 70.000000 237.000000 72.500000
81.25 72.500000 70.000000 237.000000 72.500000
87.50 72.500000 70.000000 237.000000 72.500000
93.75 72.500000 70.000000 237.000000 72.500000
100.00 72.500000 70.000000 237.000000 72.500000

Let me know if you need the whole tune and I can send it to you.

[BlackGMC]

To soften the shift a little, keep the 1->2 pressure the same, and instead increase 1->2 Torque Reduction...

The idea behind this is to prevent slippage and instead pull some ignition timing for about 0.2 seconds to soften the shift.

Thanks for the tip!!! I increased the TQ Management on the 1->2 shift by 10% (I am running 35% total now) and it stopped the truck breaking loose on the 1->2 shift at the track!!!

[Big Kahuna]

Ive got an issue whereby the motor is stalling when in gear and at slight TP%.
Vehicle is an 03 VYSS ute, stock engine 3.9's and a 3500 stall.

Its a mates car and I havent had a chance to perform a RAFIG. Am I headed in the right direction. Pre stall convertor the tune was fine but now it has this small idle issue.

[joecar]

Some people say do a CASE relearn after a TC install.

Then after that do the RAFIG if still necessary.

[arubenstein]

my truck shutters as well around 50, its like the converter wants to lock but cant decide... I could use some help as well.

I have the same issue.

Scan "TCCDC" or TCC Duty Cycle. This is the amount of commanded apply pressure to the TCC. You will see it floating around and if you also scan TCCSLIP you will see what it does. The stock TCC is designed to slip. Aftermarkets aren't, and they don't like to slip (generally). The TCM commands TCCDC as a function of TPS and maybe VSS, but I don't know this for sure.

The short term fix is to make your TCC Apply Pressure Minimum 99, and max to 100. This will ensure it never slips. The bad news is that this will cause a very solid lockup, and on a high stall converter it feels like you are even shifting another gear.

The real fix will come when EFILive exposes that TCC pressure table. I am waiting for this as well.

[Thumper]

Hi Guys
Im just about to install a 2200 TCI converter in my VX SS
All I have done to tune the box is change the shift points to my liking and play with the torque management a little. As for the rest its a little bit of a black art to me.
When I change the converter am I going to have to change any apply and release speeds or any pressures at all?

[joecar]

No, just try it and see how it goes.

[joecar]

Be sure to install TC correctly (3 engagements, TC mount pads must be 1.2" in from bell-housing-engine interface).

[MyM8V8]

Hi there Joe,

I was recommended a 4200 stall which I have ordered. It will be fitted when the 402 stroker is built and tuned. What have I got to look out for?

Thanks

[joecar]

Just try it... if it blows the WOT shift points then pull back on both the WOT MPH and WOT RPM until it shifts without hitting the rev limiter.

Do a CASE relearn so misfire detection can work properly.

[MyM8V8]

:cheers:

[Alex99]

Don't want to hijack the thread but I also use a higher stall converter and in order to maximize in-town fuel economy I started to use 3rd gear lockup. I raised the 4th gear engagement quite a bit to better utilize the 3rd gear.
Now to my problem, When shifting from 3rd into 4th it unlocks the TCC (to not stress the drivetrain too much). Due to the higher stall speed the rpms jump up for a second until 4th kicks in. This happens only if the rpms are below the stall speed (~2300rpm).
Is there anything I can do in the tune to lessen this effect? I like the 3rd gear lockup alot since I do alot of city driving and it helps quite a bit the fuel consumption.
Thanks
Alex