One messed up 3800 Tune

[Mac7504]

Great feedback, thank you; tuning is the only thing holding me back on my plans - it's scary serious business....Why can't they make an "auto tune" like they do for motos..:laugh
Sorry for the hi-jack

[MMGT1]

Hey Vode, couple of things for a trans tune in this thing:
First you need shift points aligned. Look at shift speed, part throttle shift and WOT shift. You want the 100% column to match the WOT shift. Right now it is getting conflicting information between the tables
If the engine has stock valve springs, it is not going to like the 6500RPM shift it has programmed right now for a 3/4 shift. I would lower the 3/4 shift to 5800 if this is the case
If you are going WOT you want performance, I make the performance shift, normal shift and WOT shift match in all tables
Then Force Motor Current. I do not leave the 100 column like that to bleed off all its pressure up there. I copy the 96 column and paste it to the 100 column
Desired shift time, I set both performance and normal to .175 Any faster and you risk damage to solenoids, although mine were personally set to .1 for 6 years on a 4T45E trans without issue... just sayin...lol
Your TCC Duty Cycle, I set MAX to 100 and min to either 50 or 55, depending on feel of the lock. If you find it hits too hard at 55 try 50 and see what you think. Also, you will want to raise the apply and release speeds of the TCC table a little so it does not feel like the car has an extra gear in there.
Since it looks like you are removing torque reduction in the tune, disable master function for both Abuse and Torque. I also 0 out the Spark Retard vs Torque Reduction table if you are removing all TQ management.
I see your pressure table has already been modified and would leave it as is for now.

Give this stuff a try and see what you think of it. Every driver is different and likes different types of shifts, but this should make the car feel really nice booting around town and give nice crisp shifts when you really get on it

[VodeAn]

Thanks for the advice,

If the engine has stock valve springs, it is not going to like the 6500RPM shift it has programmed right now for a 3/4 shift. I would lower the 3/4 shift to 5800 if this is the case

The valve springs aren't stock, but I actually did lower the shift point anyway but have not posed that tune file, I can post the latest one when I get home.

Look at shift speed, part throttle shift and WOT shift. You want the 100% column to match the WOT shift. Right now it is getting conflicting information between the tables.

Good catch, I didn't see that.

Since it looks like you are removing torque reduction in the tune, disable master function for both Abuse and Torque.

Actually I'd like to re-enable torque management between shifts, to take the load off. I noticed leaving it on with 4L60e's makes for a quick crisp shift, rather than a harsher one. But I will remove the abuse mode.



The vehicle is getting taken apart (by the owner), I have reason to believe the KR issues are due to the "high compression bottom end." There has been head work, but no paperwork to tell what was done, I'm guessing the heads are decked. The information I received from the owner was that the motor was at 9.4:1 compression, the L26 CR. I believe the vehicle is running on something like 11:1 compression. WELL... 11:1 compression with 10psi of boost and 93 octane is BAD, and explains the spark knock even at 13 degrees of timing.

[VodeAn]

I suppose there are some lessons to be learned here.

Lessons for vehicle owners/purchasers:
Don't buy a vehicle from someone who can't provide paperwork, or give you a very detailed account of the modifications.
If it's a vehicle I'm buying you can bet your ass I'm going to scan it with HP tuners before I buy it.
If someone else tuned a vehicle you want to buy ask who tuned it, what's your target AFR at wot, how much timing do you runat WOT? If they don't know read the tune or have someone else do it for you if you don't have HP tuners.
What's that you say? The PCM is tuner locked? Walk away, don't buy the vehicle.

Lessons for tuners (myself in this case):
When tuning don't believe a thing the owner says unless you see paper work or they can give you a very detailed account of the modifications. If you ask a question a few different times and get different answers they individual either doesn't know or is lying. It amazes me how many people will make stuff up instead of admitting they don't know the answer to a question. They might not be a bad person but are just embarrassed to say they don't know. Anyone who has taken law enforcement classes or works security/law enforcement can relate to these issues.

Whenever unsure tune conservatively, or not at all. Don't assume anything.

This all might seem obvious but when you see a different cars all the time it's easy to forget about stuff like this.

Tuning a vehicle someone else has already worked on is potentially a hot potato, if your the last person holding it you might get burned. I'll say this much though, the owner of this vehicle has been very understanding about the issues with the vehicle.