myclone

Rebuilt a 95 model 80E that went into a neighbors 71 camaro (N/A 406) with a TCI PCM. Basically its stock with only a transtar rebuild kit, transgo HD2, 34 element sprag, 2800 rpm Hughs TC, and new selonoids. Other than that its basically stock but there seems to be a problem with the WOT upshift to 3rd (or lack there of).

Short version:

At light throttle all shifts good/normal.
Manual Rev, 1, 2, 3, and 4 gear shifts good/normal.
WOT 3-4 down shift with shifter in OD good/normal.
At WOT/shifter in OD the 1-2 shift is normal but skips 3rd and goes directly into 4th.
At WOT/shifter in 3rd the 1-2 and 2-3 shift is normal.

Basically the only time I can get 3rd during WOT is if the shifter is in 3rd, manually shifted from 1st up to 3rd, or with the shifter in OD and you go WOT the trans down shifts to 3rd from 4th.

The TCI control has been verified to be working properly (tried it in my vehicle with the same set up) and all the electronics check out (verified with a DVM). Im kinda stumped as I thought I had an internal leak and was getting slip in when the direct clutches applied and the TCI control was commanding 4th since the WOT tables are RPM based. I figured the direct clutches werent being applied but the overruns were in manual third but if I understand the hydraulic circuit correctly if that was the case I wouldnt have the 4th to 3rd down shift at WOT.

Any thoughts or suggestions? BTW, I havent put a pressure gauge on it yet due to lack of time but hopefully that will happen this week if scheduling allows. Just looking for feed back before I yank the trans back out or my bud clubs me to death since I talked him into replacing a perfectly good TH400 with an 80E to begin with LOL.

TIA.

FLT

iTrader: (1)

Does this unit have bonded pistons or aluminum pistons? The aluminum ones do crack from time to time. Also you should probably check the seals for the 2-3 accumulator piston's. I have seen that sometimes the seals that come with the t-star kit are like undersized. They seem to go into the housing real easy with next to no drag. Also make sure that the 3/8 12point bolt in the center support is tight and doesn't rock in the case. You could be loosing oil pressure between the support and the case. Also if I remember correctly they have you drilling the valve body on the worm track side and installing a very small cotter pin. I left it out once and I believe I had no third gear on the dyno. I could be wrong it was quite a while ago. In the SK they also have you leave out a fairly large check ball that is located inside of a sleeve with an oring. This is how they are increasing the direct clutch feed oil. Always replace the oring it is in the overhaul kit. I do remember talking to a guy that used the same TCI controller and he was telling me that they were having pressure control issues. I guess the programing instructions were wrong because they said that the pressure was acting backwards with the tps. I'm not sure if it was the directions or the installer but something else to consider. Please post up what you find. Vince

myclone

Thanks for the info Vince. To touch on the things I have answers for...

Cotter pin in the worm track is installed (reason I remember is I forgot it and had to go back and install it).
Lube feed bolt is tight.
Any/all seals were replaced that were in the kit.

TCI control....sigh... I tell ya....I really like their control (for the money) but it leaves a LOT to be desired sometimes. The instructions are about as vague as you can get in certain places and prying detailed info out of TCI is like digging rocks with a plastic fork. Im an electronics tech and even I had to do some head scratching on the install to get things working. Once youve done one or two and know all the "little things" that the TCI instructions dont mention theyre a breeze but until you get a couple under your belt you'll wanna pitch it in the trash more than once.

I talked this same issue over with a fellow 80e builder/TCI user and one thing Im going to check is the shift "time" setting in the TCI control. If its too short it doesnt wait long enough for the mechanics/hydraulics to do their thing and will go ahead and command the next shift. Since I dumped the program from my TCI unit into his and my 80e is built just like his I figured we would need minimal tweeking on the tables. However, his TC is a 2800 rpm where as mine is a 2600 so that may be goofing us up if the time to shift setting may be too short for the extra 200 rpm stall difference.

Again, thanks for the suggestions Vince and I'll post up what I do/dont find when I get my hands on the car this week.

James B.

iTrader: (1)

Post up your TCI file and let me have a look at it. I run a TCI controller with my 4L80-E and it is absolutely ISSUELESS and performs perfectly predictably exactly the way I want it to EVERY time. TCI's instuctions and support may be lacking but the hardware certainly is not.

myclone

Im at work right now but I can send ya the file when I get home in the AM.

Dont get me wrong Im not bashing the control...for the money its a nice piece and the only issue Ive had with the control itself was mine was bad right out of the box and had be shipped to FAST for warranty repair. Took about three weeks for it to show back up at my door step and has been running fine ever since and the guy at FAST who does TCIs repair was a super nice guy....we ended up BS'ing on the phone for prolly an hour.

The control is lacking in features compared to the other units that are out there (cant data log/monitor the TOSS for one) but according to TCI their guys are working on more bells and whistles right now. Then again its a few hundred bucks cheaper than the other units too so I can understand the lack of bells and whistles to keep the cost down.

My main gripe (if you want to call it that) is the manual could be a little more informative/detail oriented. What they provide is more of a "quick start" type deal just to get your average car guy up and running but it'd be nice to have an "advanced" chapter for geeks like myself that want to know/tweek everything. As it stands right now you have to call up TCI, leave a message for an engineer, and then wait for him/her to call you back if you want detailed info. So far Ive done that twice with no call back and I ended up making several calls and finally caught an engineer that wasnt too busy to come to the phone.