I am about to get into burning proms, I have the 460LE. T

here is quite a bit to do with the prom on these Computer controlled tranmissions I was hoping some would come forward and share their experinces. From what you have done with the TQ lockup in OD, to changing shift RPM.

Main line pressures, downshift pressures, Line pressure in WOT, TQ engage release ETC.

It seems to me you could really get these things dialed in nice. I am not a fan of the stock 460LE, but it looks to me with a bit of prom burning you have a tranmission that you can "electronically" put a shift kit in tailored to your needs.

I'm just hoping some here have some good experiences. I am really interested in locking up the TQ almost 100% of the time it is in overdrive.

Thanks guys.. lets here what you;ve done.. if you have.. I think Grumpy has a Electric tranny?

 

The 4L60E has a few issues that need to be addressed that require mods to the valve body, also. Transgo makes a kit for it, and I have had excellent results from it! That is where I would start on working with a 4L60E.

 

What kind of issues? I would hate top play witht he prom and toast the tranny ecause it can't hold up to my modifications

 

Yepper, thou a 4L80E.

Mines in a 7.4L 3/4t and it's purpose in life is towing.

I was rather lucky and hunted around until I found a later Heavy Duty application and then compared tables. So as to get a grasp of what to do.

The upshift and downshift tables for normal and high performance settings all needed some minor tweaking. On the low MPH vs TPS I upped the MPH settings slightly, and then in the high perforance mode dropped the shift points.
I use the TCC in third gear at low throttle openings now.
Just moved the line pressures around a few PSI.
And I dropped the shift time setting down.

If and when I find another 4L80E for the right price, I will be installing it in the GN, weight not withstanding. No TV valve, no jacking around with the govenor, independent RPM vs gear shift points, man they are just too slick, IMO.

Mines a 91, and I just can't wait to get it updated/overhauled , and I've been thinking of using a later PCM just for grins.

I did some tuning on a 95 Caprice, and it was nice being able to short shift first gear, we'd changed the final drive to 3.4s, and with the 3.06 first gear just really overwhelmed the tires, so we short shifted first, to be able to get into second, and get going rather then just spinning the tires.

Hmmm, you might try looking at some EE masks for the later F-Bodies, and Cop Cars, to see what they did, in the various cals.

 

Grumpy,

It looks like you have really had some great results. One thing I was kind of thinking/concerned about.

In over drice It seems to me at 55-65 that the TQ is always in a non lock up mode..

IE. slight raise in elevation, and slight throttle it seems to loosen up, or free the TQ, I get a slight raise in RPM, from 1500 to 2000k rpm.

Now I know this isn't a downshift, it seems more like it just lets loose to allow some light accel maybe perhaps so the transmission doesn't buck.

Anyways I would think both Mileage wuould go way down, and TQ wqear would go way up.. wondering if you've done much with that..

I just can't wait to dig into this stuff..carefully of course.

 

some things to wathc out for. tire chripign shifts are hard on the input sprag. the overun clutch doesnt take to well to high speed engine braking. and keep the main line pressures within %25 of stock. if you dont i guarentee youll be buying a pump. ( I broke a pump ) aside from that stuff set the shifts points and only adjust line pressures etc when the trans has a difficult tiem pulling into the next gear. you may want to consider getting it upgraded into a 4l65e. same internals just heaveir duty parts.