Hey guys, finished my 96 Impala / LSX B15/ LSA swap build a few months back (well, work in progress, but it ran...for a little while) and ran into some trans issues right off the bat. I'll make a long story very short, not blaming the builder but it basically seems like a mix of bad luck and a mishap with the converter selection that the builder is working with me on, but I couldn't wait on that so I ended up purchasing a new Performabuilt level 3 and a circle D converter which I should be getting soon .

One issue I have is that i'm running an e67 ECU/T42 TCM from BP Automotive and the operating system is showing up as a CTS-V in HP tuners and utilizes all the features of the LSA extension harness, yet bill from BP set it up to control a 4l60e. Not exactly sure how he did this, I am no tuner, and he basically just said it was all ready for my tuner to play with. What i'm seeing now though, looking at the logs, is line pressure is showing up as 119 and my tuner seemed to have the part throttle shift points way too close together (felt terrible driving around town, not sure how much of that was from the trans/converter issues but it appears like it was being commanded to shift through all 4 gears by like 25mph and wouldn't downshift without some massive throttle input).

My tuner said he put the line pressure back to where it was originally from BP, but BP couldn't confirm that they were initially stock tables. Bill from BP said they should have been, but also could have been slightly modified ones he had. I really need line pressure, shift points and TCC lockup tables to be stock right now since both my previous trans builder and Performabuiilt insist on using stock tables as a starting point and only modifying shift points and TC lockup as needed.

Could anyone help guide me as to where to find the stock tables and explain how I could upload them into HP tuners?

 

You can download a stock 98 tune from HP Tuners. Not sure about other stock tables as my car is a 98 Z28.

IMO, how you adjust shift scheduling and TCC apply release will depend on the stall speed of your converter, the profile of the cam, and rear end ratio if not stock.

This scenario is just one example. I have a Yank PY 3450 converter/stock 3.23 gears/Peformabuilt Level III 4l60E tranny.

I like to keep my maximum speed thru my neighborhood at 20 mph or less. With my reasonably higher stall the engine RPM would raise and the TC would slip in first gear and not shift into 2nd as I drove thru my neighborhood to get to my house. I have a reasonably mild exhaust (LT's, cats, Magnaflow Catback). But I also have a D1 Procharger, with a big red race valve. It gets noisy when cruising along at 15 mph. Some neighbors don't mind the noise, others do.

In the stock table setting at a TPS (throttle position percent) of 19 percent I had to be traveling 12 mph before it would shift into 2nd.

All 4L60E have the same ratio (3.06, 1.63, 1.00, .70). As you can see 2nd is not quite 1/2 of first gear. So getting into 2nd at lower TSP and mph gets me into 2nd quicker. So at just off throttle I reduced mph down to 8. So my 1>2 shift happens at 8 mph rather than 12 mph or higher.

However, if I immediately go to WOT on takeoff (wide open throttle) the 1>2 shift occurs at 37 mph.

When you look at the table in HP Tuners you can view part throttle shift scheduling under: Transmission>Shift Scheduling>Part throttle Shift

You adjust these values to suit your driving style. But as you can see when looking at the stock shift scheduling tables the TPS and MPH values were adjusted for a mild stock 5.7 cam that makes a reasonable amount of vacuum with a much lower converter stall speed.

In other words, if your engine doesn't run very well under 1600 RPM's combined with a very high stall and a gear set that is 3.73 or higher, you don't want to set shift points to a higher gear if the result of the shift change drops rpm below 1600 rpm.

The same rule applies for converter lockup. As a result this means you will have to adjust the apply/release TCC values as well to correspond to the adjusted shift points. This issue is addressed in the link below.

Drive-ability is the area of the tune that many tuners (from my experience) don't want to touch because it takes times and each driver is different. What I like you might not like. Some drivers like to wake up the neighborhood - I don't.

Search this forum for transmission tuning tips. There are a ton of posts to read. IMO this is a good one in link below.

Be aware though that when you start making changes, a value change when upshifting also affects downshifting. There should always be about a 4 mph difference between an upshift and a downshift. Also - always match WOT values with the corresponding WOT values in the part throttle tables.

https://ls1tech.com/forums/automatic...tm-w-pics.html

Tip: when copying tables always make a backup first. Copy and paste a table, a row, or a column is what you refer to as upload. Am not sure you can upload.

 

If you have HP Tuners could you post the tune file?

What you are referring to are the force motor current tables as well as the shift pressure modifiers per gear.

Shift scheduling, part throttle and full throttle etc don’t affect line pressure.
Being able to see the tune would tell a lot there.
BTW, they are tps vs mph. So having the correct gear ratio and tire size affect all that greatly.

I have a Performabuiilt Level 2 in my C5 Vette. I remember they said don’t adjust shift pressures. Our shift kit does that for you.
Interesting though, Camaro, Trucks and Vettes are all different in the stock tune files. At any rate, I left those tables alone!
Good trans though. Still shifts flawless 9 years and hundreds of drag strip passes later.

I think there is only one control line polarity difference between the 4L60 and 4L80. But not sure what BP changes in the TCM to do that.

 

We have people return the line settings to stock because in many cases with the stock trans the line has been turned up alot to get a good shift by individuals and tuners, The issue with this is with our unit this will cause extreme overly aggressive shifts just in normal driving which is harder on the trans than necessary not to mention uncomfortable. The stock tables make the best starting point for this,
Frank

 

To OP:

You might want to invest in this download from Maslic's website. It is a digital file you download for a small fee. Once downloaded you can view the digital file as a PDF on screen or print a hard copy of the PDF.

http://www.masterenginetuner.com/

In the manual there is one chapter devoted to the 4l60e transmission. In it he explains shift scheduling, shift time, line pressure, torque multiplication, and TCC tuning. He also has a 4l65e table that has been modified for driveability because the engine doesn't behave very well under 1600 rpm.

He also explains idle tuning and the throttle cracker and throttle follower tables and their purpose. Nailing down all of these parameters in your tune helps with driveability.

You might want to post the cam profile as well as the stall speed of the converter and rear end ratio.

 

Thanks for the explanation.

 

OP: More info here from Performabuilt Tech.

https://www.performabuilt.com/tech-info/

 

Lots of good advice and resources in this thread - thanks to all!

Just wanting to add I had good experience using Bluecat's tool as a starting point for setting my shift points in my 95 9C1 with 4L60E and a 4.10 gear swap (stock cam/converter). Will be using it again with planned cam/converter changes. Here is a link to Bluecat's thread and tool on HP Tuners - the tool is linked/attached in posts 210 / 211. Bluecat Trans Tool Thread

Hope this helps and is useful to OP and others -

Jim

 

Thank you to everyone for the help! Bill from BP ended up sending me a new calibration with the stock shift tables that I uploaded and used to drive to the tuner. Car seemed to shift fine.. She made 660RWHP on the dyno on E53 at 13PSI.
We street drove it around and it felt great, possibly may need to raise the 1-2 shift point a little at part throttle but otherwise everything was working as it should. The Performabuilt trans and Circle D 3200 feel awesome.

I did notice two issues driving home though, I think they may be related.

First, when the converter locks at lower highway speeds (say 60mph) at VERY light throttle input, there is a sort of intermittent shutter/hiccup. Doesnt seem to do it when the converter is locked at higher speeds, so I think it is the engine lugging. The ID1050X don't seem to like idle too much either (we got it idling good but it took some work) so that may be adding to it as it only happens when coasting or at just off idle throttle conditions when the converter is locked.

The second problem is a lurch when coming to a stop. Seems like the converter is staying locked when slowing down, and the lurch I am thinking is from the converter unlocking just before the stop.

Any tips? I'm going to send a log to John from JTM who did the dyno tuning, he was great and i'm sure he'll have an answer. Just figured i'd get a jump on it and see if it's something I can do myself

 

I have a mild but noticeable coastdown bump as well that showed up when I went to 4.10s from 3.73s. I have concluded it is the closed throttle 2-1 downshift, even though shift speeds were adjusted for the new gears. TC is obviously unlocked, so I am looking at throttle ** EDIT: cracker/follower ** settings, and making sure I am not in fuel cutoff. I haven't had a chance to test changes, but you might want to check these as well.

Hope this helps -
Jim

 

It's my understanding that as soon you let off the throttle the converter is supposed to unlock. If it doesn't then assume the TPS (volts) is out of adjustment at idle.

ChopperDoc has a tutorial on TPS adjustment.

Maslic has a section devoted to adjust idle setting, throttle follower and throttle cracker tables. Link below from HP tuners explains how.

 

Misfires can issues with lockup. On lockup you can feel shudder as it hunts to lockup or not. You might have to adjust for misfires. Maslic explains this in his manual.