4L80e install - Questions

[critter]

I was teasing about the Demon. That's your carb and you can do what you want with it. Even if that means leaving it in the box. LOL.

Hey, glad to hear you're playing with the toys. It's no fun to have them and not get to piddle around. Enjoy.

[critter]

I snuck out for a quick test tonight before the storms moved in. It was only to the end of the street and back but I have say that paddle shifters are the shiznit!

[Steve Chryssos]

I'm glad you are finally having fun. And that right there is the first ever application of a Trans Am steering wheel with a paddle shifter. Congrats.

[aronhk_md]

Chris,

With the compushift setup do you get compression braking when downshifting? If so is it adjustable? I know that with one of the other computers you dont......but I think its a computer function and some will?

Aron

[critter]

Mine is the TCI and no, I don't think you do unless the trans is built for it. Someone smart needs to speak up here if I've got this wrong.

I'm calling it a done project, even though my speedometer isn't working yet. That's got to be a wiring issue. I took it for a drive this morning:

http://www.youtube.com/watch?v=dveiiwrdNNQ

[aronhk_md]

Thanks Chris.....video looks great by the way. Just as an aside.....one of the hardest parts about using a paddle shifter I imagine would be in a turn. I am upgrading my steering box to a 1987 GTA/WS6 box which has a tighter steering ratio than the earlier trans ams. Paid $25 plus shipping for a used one, and its apparently bolt in other than adapting with metric fittings and a new rag joint I believe. Gonna try it anyway...lol.

I cant wait to get to my 4L80 project, but its back burner for the moment with a few other things first. I'm going to try designing my own "paddle shifters" though using plates and instant switches.

I noticed the delay on your setup between the click of the paddle and the shift. That is adjustable with the computer, correct?

[critter]

Yes, the clicking is the shifts. I'm still learning how to use it. One thing I know is that the transmission takes much longer to respond under part throttle than when I'm into it hard. You can hear that in the video. There may be a way to do some tuning regarding that but I've not looked into it yet.

[machota154]

Critter, How did you hook up the paddle shifter to the stock streering wheel.???

[critter]

Call Steve at Twist. He's got it now. He can machine you a paddle setup like mine. The paddles bolt in place of the stock collar. The adapter he provides mounts the stock wheel. You will lose your horn assembly unless you're creative like me and build a setup to make it work but other than that it's a bolt on. Call him.

[machota154]

Thanks for the info. I am following your build, cant wait for more post on your test drives. Thanks again, David

[Steve Chryssos]

Hi Aron,
Engine braking is not a function of the paddle shifter or the computer. It's a mechanical modified 2-3 shift valve that changes when the overrun clutch is applied. The mod is not available for 4L80E's

As for the Shrifter®, it takes 125 milliseconds for the paddle shifter to TELL the transmission to shift. You hear two clicks for each paddle shifter input: the first click is the sound of our relay circuit closing. Once the circuit is complete the TCU has been told to shift.
The second click you hear is the relay opening back up. That occurs 1 second after the circuit closes. This built in safety measure prevents the user from inputting double taps.

After the signal has been sent (.125 sec), the transmission itself takes time to complete the gear change. Chris' trans sounds like it shifts fairly quickly. He could raise line pressures at low throttle angles to speed up shift times, but to some degree, the trans must be built on the firm side to take advantage of the tuning. And you have to WANT the firm shifts at very low throttle angles.

[aronhk_md]

Thanks Steve.....guess thats one downside to the 4l80e. Id really like compression braking. Guess its not a perfect world though. What keeps me from going with a 6 speed is the time during shifts it would take for the turbo to completely spool again and also I dont know of any 6 speed capable of handling 1100 hp.

[Steve Chryssos]

I know that engine braking sounds like a focal point, but the right torque converter and proper trans set up are way more important.

[critter]

My speedometer is still not working. I thought I'd messed up the wiring or something but I took it all apart again today and checked. That appears to be correct. I have the orange wire that is speedo out from the TCU going to the speedometer.

I stripped that wire back and hung a volt meter on it just to see if it had any signal. I've got zero voltage. I tried it in gear and out of gear, rolling and setting still (car has rear end up on jack stands). Shouldn't I be reading something there?

[Jake's Performance]

Chris,
Swap the speed sensors from front to rear and see if that fixes it.

The TCU should be seeing VSS to operate but...

Here's a 4L80E with transbrake we installed yesterday.
http://www.youtube.com/watch?v=00qx69D-VDY

[Jake's Performance]

I can do a 4L80E with engine braking in 2nd and 3rd, possibly in 1st as well.

[aronhk_md]

streetfytr - those are important too, but compression braking would still be nice.

Jake - You mentioned you can do it, but can it be done without sacrificing anything else in an 1100 hp car? Also you mention possibly in 1st....has this been done or just ideas you have to try?

Can you do this with any of the computer setups?

Sorry Chris......didnt mean to hijack your thread.

[Jake's Performance]

During the year of designing and testing to develop my transbrake for a 4L80E I learned several potential mods for the 4L80E.

I can do a spragless VB for the 4L80E that will eliminate the sprag in big power applications. This would also give engine braking in 2nd gear.

I can do engine braking in 2nd gear with a sprag type as well.

I can make it a 6 speed (waste of time IMO and also detrimental to the reliability).

Using paddle shifters you can put the trans in D3 and have engine braking in 3rd stock.
I can pretty easily make it have 2nd gear braking. Low gear is a bit more complicated but I can do it as well.

We have a few VB's in the works.

The full engine braking VB would actually be beneficial in big power applications and the spragless is best in a race only BIG power application.

[aronhk_md]

I will be in touch with you when I'm ready Jake. I decided not to buy from Hughes because I'd rather buy from you, but due to job circumstances I am not sure exactly when it will be yet. Thanks

[critter]

So I'm back again.

I figure I need to deal with the lack of neutral safety switch and I'd also like to put a gear indicator light up on the dash for when I'm using the paddle shifters. So I was poking around on the Dakota Digital site and came up with the following products:

http://www.dakotadigital.com/index.c...prod/prd60.htm

And:

http://www.dakotadigital.com/index.c...prod/prd64.htm

So other than having another mess of wires to run, what do you think? That should get the job done, shouldn't it?