TCI 6 Speed Auto
Perhaps this is off topic, but before anyone decides to put an Allison behind a LS engine, I recommend you contact someone from Allison and discuss the input rpm limits of the transmission in question, older allison transmissions could not safely operate at 4500+ input shaft speed, and the older transmission case would not contain the debris generated, this created real risk of driver foot & leg injury. Even with the significant improvements and extended rpm range of current diesel light truck engines, they still don't have the range of crankshaft rpm that a GM LS can generate.
my guess is with a paddle shifter you could man. shift all 6 gears, but with a rachet shifter, since it only has provisions for 4 gears, you would man shift 1-2-3-4, and in fourth it would shift 5 and 6 based on control unit settings
Super Chevy mag has an add in the June issue with some info (along with a feature on my car, hint, hint, lol)
Super Chevy mag has an add in the June issue with some info (along with a feature on my car, hint, hint, lol)
TECH Fanatic
Joined: Jul 2005
Posts: 1,685
Likes: 7
From: Beebe, Arkansas
Former Vendor
Joined: Mar 2009
Posts: 39
Likes: 0
Pretty cool that you guys decided to do this. I'm not sure if Russ and Dan convinced someone that it would be a good idea or what. Is the valve body in this thing modified for quicker actuation on the accumulators / clutches / bands vs stock? Also I'm guessing the OD (I can't even remember if this is a clutch or a band) element is beefed up significantly vs stock? The GV unit has a lot of limitations and this should eliminate most of them so long as the OD element is solid.
Yeah I missed this back in whenever as well. I have been wanting a 6 speed auto of some sort in my Formula and was about to just forget about it when I see this thread rise from the grave.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Here's a link to a video of the 6X in operation. This is in a Buick T-type with a GM 502 engine.
http://www.cpgnation.com/forum/tci-p...logy-2280.html
http://www.cpgnation.com/forum/tci-p...logy-2280.html
Teching In
Joined: Aug 2005
Posts: 17
Likes: 0
old tricks are new again no. the physical layout/operation of the 4l60 prevents this type of trickery. the 4l80 is essentially a th400 with the OD gearing ADDED on. 700r4/4l60 were technically new designs.
FYI for anyone who cares... TCI is not doing anything new with this product. there have been smaller race trans shops that have been doing this for years (JET and others). The only difference is TCI has spent the extra time/money to refine the electronics to make it reliable. it also looks like they have used non-standard gears to make the trans more usable in this 6x config
if you are honestly thinking about the TCI 6x you should use due process and compare it to the factory 6L90E. if you go to fatboyracing's website and use their transmission comparison calculator and enter in the TCI's gear ratios and compare them to the 6L90 you see that the 1-2 shift on the 6L90 isnt ideal (big change in angle compared to next gear), but the TCI seems too close (1-2 shift at redline only gets you about 10 more mph). and the final ratio is much better for cruising (couple hundred rpm).
just my 2cents
FYI for anyone who cares... TCI is not doing anything new with this product. there have been smaller race trans shops that have been doing this for years (JET and others). The only difference is TCI has spent the extra time/money to refine the electronics to make it reliable. it also looks like they have used non-standard gears to make the trans more usable in this 6x config
if you are honestly thinking about the TCI 6x you should use due process and compare it to the factory 6L90E. if you go to fatboyracing's website and use their transmission comparison calculator and enter in the TCI's gear ratios and compare them to the 6L90 you see that the 1-2 shift on the 6L90 isnt ideal (big change in angle compared to next gear), but the TCI seems too close (1-2 shift at redline only gets you about 10 more mph). and the final ratio is much better for cruising (couple hundred rpm).
just my 2cents
11 Second Club
Joined: Feb 2008
Posts: 317
Likes: 2
From: TN
Here is the problem with 6L90E/6L80E VS the TCI 6 sp/4L80E in most any car.
1966 Corvette 6l80E fitments.
Trans Tunnel had to be removed and moved up. On this car that means bottom of dash had to be trimmed off. Doing that means custom cut dash pads made as they extend down to top of tunnel. Yoke for 6L80 is big and one for a 6L90E is even bigger. Smaller 6L80E yoke still required cutting tunnel to make it wider to provide clearance for it. Stock pan is low to ground. I changed to G8 pan and filter as it gave me little over 1/2 more clearance. Probably miss a few more details.
1964 Corvette 4L80E and or TCI 6 speed fitment
One ear on bell housing had to be removed. Was able to trim out stock placement trans x-member and add bracket to it. So less work needed to install on same bodied car.
Both transmission have their pluses and minuses. Double overdrive is not that helpful mileage or performance wise. I'm using a 3.08 rear end with the 6L80E, so a vette with 5/6 speed would need a 4.60 rear end to match it in 1st gear and due to 1.15 4th gear a 3.54 rear end in 4th gear.
There is a video posted in this forum of a vette with 6L80E, yank converter with modified engine running in high 9's with 3.42 rear end, so I guess 6L80 is not that bad at strip.
Everyone knows what 4L80E can do. Could it do it better or worse if it had same gear splits as TCI 6 speed? Then again what you have to remember is the TCI 6 speed's gear splits may be better than stock 4L80E on street as it keeps you in the engines power band so you just may see a little better around town fuel mileage.
If you don't believe that, take a look at what the Europeans and Japanese are doing with their Direct Drive multi geared (more than 6 gears) transmissions. Narrower splits between gears. It's all about using mechanical advantage to move the weight with less stress on engine.
1966 Corvette 6l80E fitments.
Trans Tunnel had to be removed and moved up. On this car that means bottom of dash had to be trimmed off. Doing that means custom cut dash pads made as they extend down to top of tunnel. Yoke for 6L80 is big and one for a 6L90E is even bigger. Smaller 6L80E yoke still required cutting tunnel to make it wider to provide clearance for it. Stock pan is low to ground. I changed to G8 pan and filter as it gave me little over 1/2 more clearance. Probably miss a few more details.
1964 Corvette 4L80E and or TCI 6 speed fitment
One ear on bell housing had to be removed. Was able to trim out stock placement trans x-member and add bracket to it. So less work needed to install on same bodied car.
Both transmission have their pluses and minuses. Double overdrive is not that helpful mileage or performance wise. I'm using a 3.08 rear end with the 6L80E, so a vette with 5/6 speed would need a 4.60 rear end to match it in 1st gear and due to 1.15 4th gear a 3.54 rear end in 4th gear.
There is a video posted in this forum of a vette with 6L80E, yank converter with modified engine running in high 9's with 3.42 rear end, so I guess 6L80 is not that bad at strip.
Everyone knows what 4L80E can do. Could it do it better or worse if it had same gear splits as TCI 6 speed? Then again what you have to remember is the TCI 6 speed's gear splits may be better than stock 4L80E on street as it keeps you in the engines power band so you just may see a little better around town fuel mileage.
If you don't believe that, take a look at what the Europeans and Japanese are doing with their Direct Drive multi geared (more than 6 gears) transmissions. Narrower splits between gears. It's all about using mechanical advantage to move the weight with less stress on engine.
