tci 6 speed

blackv6

Member
Joined
Nov 1, 2011
Building my gn and was wondering if u guys have any good or bad on the tci 6 speed auto. i want to get one for my car. with the six speed maybe able to run a big gear for takeoffs and be able to cruise at highway speeds without winding engine out.
 
I have seen a couple GNs running the TCI 6 speed, however I haven't seen one on a V6 turbo yet. The ones I saw had the V8 swap. The TCI 6 speed is a modified 4L80LE. You would need to do mods such as crossmember, shifter linkage, etc. The trans fits fine in the tunnel. The main advantage with a 6 speed is the gear ratios (lower RPM all throughout). But you need to be making decent power to take advantage of it (probably 400-500 HP min).
 
It seems many people are believing these so-called 6 speeds are different than normal 4L80E's, they are not.
Transmissions with the overdrive carrier at the front of the main drive components activate the overdrive between 1st & 2nd and again between 2nd & 3rd.
Yes, it becomes a 6 speed but not in thinking it has 2 overdrive gears.
This "technology" can be applied to GM 200-4R, 4L80E, Fords A4LD, E4OD, and Chryslers A500 & A518 models also, nothing new here except advertising tactics.


Kevin.
 
I stand corrected, The 6L80E is a different animal, I "assumed" this was the reprogramed 4L80E that the aftermarket first used the term in the early 90's using the 4L80E and "spliting" 1st and 2nd with the overdrive clutch.
From what information I just picked up, I can see it has potential as a "truck" transmission, but not for a performance vehicle unless your willing to change the rear gearing as well, because a 4.02 first gear with 3.42 out back would be the equivelent of a 200-4R with a 5.00 rear gear in first.
I see the possibilities, but just doesn't make any financial sense. If the 200-4R won't hold up for your power level, a 4L80E would be the smarter choice, and that isn't exactly cheap either, but would simpler in total than a true 6L80E conversion and rear gearing change.
Good luck

Kevin.
 
The TCI 6 speed is a 4L80E with modified planetaries and the shift solenoid setup is also modified (I think there is a third solenoid added instead of the standard 2, could be wrong on this though). It truly does give you 6 speeds plus lockup. What's cool is you can also go between manual mode and automatic mode on the fly with the EZ TCU controller. No need to play around with valve bodies. There's plenty of V8 guys running this trans and they love them. Plus they are able to handle about 850 HP, more if you add the nitrided clutches and billet shafts. And they come with a limited lifetime warranty.

The 6L80E is still pretty new and there's not a huge aftermarket for it yet. It is a much bigger transmission. Plus it can't handle the same horsepower the TCI unit can, yet.
 
yeah I plan on running larger gear in the rear. I was thinking a 4.10 or steeper to help with turbo lag. We plan on making 950 hp with this car and I want to be able to drive on the street without sacrificing performance on the top end and bottom
 
I have a TCI 6x in mine. You need a custom shifter linkage, new crossmember, have to work out a bellhousing issue and new drive shaft and get a tps split harness. It fits in the tunnel with no issues or modifications.

Its a 4l80e modified by them to be a 6 speed. It comes with an awesome computer that you can modify every single aspect of the transmission, from shifting so hard it makes your teeth rattle to so soft your not sure it even shifted. Lockup timing, shift points etc. Also you have the option of the paddle shifters. So far it works amazing but no real road time on it yet

this is my install thread if your interested
http://www.turbobuick.com/forums/ge...987-pro-touring-grand-national-ground-up.html
 
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