TCI® Pushes The Envelope Of Drivetrain Technology

[CPG Marketing]

The new 6x Six-Speed Transmission uses six automatic gears to give you the best in performance and fuel economy

Just a few short years ago, automotive giants like Ford, General Motors and even Mercedes Benz were touting new six-speed automatic transmissions that were supposed to be cutting-edge technology. And some of the designs were—at least in terms of complexity. However, a problem with many of these six-speed transmissions was they were designed exclusively to increase fuel economy and could handle only minimal power levels.

For racers, hot rodders, muscle car enthusiasts, or anyone who occasionally tows something in a pickup, these transmissions aren’t anything to get excited about. But now, TCI® has changed all that with its new 6x Six-Speed Transmission, a six-speed automatic that will work in just about any application. So after all the hoopla, it wasn’t one of the international automotive conglomerates, but the small performance company from Mississippi that produced the first six-speed automatic transmission capable of handling 850 horsepower. And now TCI® is ready to set the rest of the automotive world on its collective ear.

6x Six-Speed Transmission

Designed to be a direct bolt-in with GM LS-series engines as well as big-block and small-block Chevys, the 6x Six-Speed benefits everyone from kit car builders, to drag racers, to someone looking to get a few more miles per gallon in their tow rig. And because it uses GM’s 4L80E casing, it will fit in most chassis. The 4L80E design is so popular that you can get crossmembers for a variety of different chassis out of most performance parts catalogs, and all will fit the 6x Six-Speed. TCI® is also working on bellhousings and adapter flexplates for small block and modular Fords as well as SB Chrysler applications that will be released in June of this year.

“We’ve been developing the 6x Six-Speed for about three years trying to make sure we got everything right before we released it to the public. GM came up with a six speed transmission called the 6L80E,” explains TCI® Brand Manager Stanley Poff, “but the truth of the matter is that the stock 6L80E just isn’t robust enough for high horsepower applications. GM had to put torque management on the engine just to keep the transmission alive."

The secret of the 6x Six-Speed Transmission success is the planetary shown here.

Of course, cramming two extra gears into a transmission case originally designed for only four is no easy task. And while no one at TCI® is ready to explain exactly how it’s done, they will say it required an entirely new planetary gear set, a new valve body design that is currently patent pending, and an additional solenoid that was never a part of the original 4L80E design. But the benefit is a transmission that’s efficient, can handle huge power levels and improves the performance characteristics of just about any car it’s installed in.

“We worked very hard to broaden the gear range versus a regular four-speed transmission,” explains Kevin Winstead, a member of the TCI® engineering team that developed the 6x. “There would be no benefit to simply putting in two extra gears but keeping the range the same. Instead, we developed an entirely new planetary gear to make first gear lower, yet maintain overdrive in sixth gear. So the low gear in the 6x is lower than a four speed transmission. This provides good acceleration off the line, as well as a relatively low rpm on the highway for comfortable cruising. This translates into increased performance and improved fuel economy.”

The gearing for the 6x Six-Speed works out to a 2.97 first gear, 2.23 second, 1.60 third, 1.18 fourth, 1.00 fifth, and 0.75 for sixth—which is overdrive. Reverse is 1.76. This means there is not only a great gear range packed into the 6x Six-Speed, but the splits are also quite tight.

TCI® valve body specialist Bob Harrison designed the 6x valve body to function with OE style shift solenoids. This was what made the project possible. It’s where the real science takes place. According to Winstead, “This is what allows TCI® to patent the 6x. Our entire engineering team worked together to design and build a functional prototype in just a few short weeks. That’s when the testing began. We have tested this product more extensively than any product that TCI® has ever designed…and we did all of it in-house.”

The black line in this data log represents the engine rpm. As you can see, with the 6x transmission, the engine stays in a very narrow rpm range. The result of this is that the engine is more efficient and performance is improved.

“Those gear splits are part of what makes the 6x so great,” Poff says. “We spent a lot of time working with the transmission and the TCU (transmission control unit) to get the shifts at the best spot and maximize the performance of the transmission. If you take this six speed and replace a four speed in a car without changing anything else, you will get a noticeable performance gain. When you are accelerating, the six speeds keep the nose of the car in the air all the time. If you have a four-speed, there is a longer pull between gears, and when it changes gears the front of the car tends to nose over until the engine can get back into its power range. With this six-speed the gear splits are tight enough that the engine always stays in its optimum rpm range, and it never lets the nose fall down.”

Both Poff and Winstead say that the 6x was designed to work perfectly in a variety of different environments. This means that it will work just as well in a lightweight fiberglass-bodied street rod, as a heavyweight ‘60s era cruiser, as your tow rig. The key is the TCU unit that TCI® has developed to go with the 6x Six-Speed and the correct choice of torque converter.

Because of its groundbreaking design, the 6x Six-Speed Transmission will only work with the TCI® electronic transmission control unit. But this is a good thing because the TCU builds almost unlimited flexibility into the system which allows you to tailor the transmission’s performance to your liking. This includes the shift points, how hard the transmission shifts, and many other factors. You can even tune the transmission so that it shifts differently at part throttle and full throttle so that you get a comfortable, fuel efficient ride during everyday cruising but also maximum acceleration if someone happens to challenge you at a stoplight. (Not that we condone that kind of stuff, but hey, it’s there if you need it.)

The TCU also makes installation of the 6x Six-Speed easy enough to perform an implant in your car or truck on a Saturday in your driveway. The 4L80E case already fits in most GM vehicles, and only minor modifications to the chassis or crossmember are required to get it to work with just about any car or truck you can imagine. And because the 6x is electronically controlled, there is no need for a frustrating TV cable. TCI® even has a throttle position sensor available that hooks right up to carbureted applications and takes the guesswork out of the process. On the tail end, the 6x mates with a driveshaft yoke for the Turbo 400 transmission, which is available just about everywhere.

Once the transmission is in the chassis and mated to the engine, the rest of the process is virtually plug-and-play. The TCU comes from the factory pre-programmed with the correct calibration files, so all you have to do is take it out of the box, plug it into your laptop and use the included programming to tell the TCU your tire diameter, rear gear ratio and throttle position at full throttle and idle. That’s it.

If, however, you don’t have a laptop computer or prefer not to use one, TCI® also offers a digital touchscreen controller. The touchscreen controller (part #377525) not only simplifies the process even further, it also allows you to make adjustments on the fly without the need to fire up and plug in a laptop. The TCU also allows you to switch to a manual mode and switch gears with an F1-style TCI® Paddle Shifter or a tunnel-mounted shifter with a "bump switch" setup. Finally, TCI® even includes vehicle speed sensors in the package so that there is no need to go hunting for parts to get your car back on the road, and you can be certain that everything is compatible.

Customers have the option of ordering just the transmission or a complete package of parts developed to work together for maximum efficiency and performance. The 6x Six-Speed package includes nearly everything you need to get on the road including the 6x Six-Speed Transmission, the electronic TCU, a wiring harness, paddle shifter, dipstick, transmission cooler, and even three gallons of the TCI® proprietary Max Shift™ automatic transmission fluid. The only thing not included is a torque converter, and Winstead says it isn’t part of the package on purpose.

6x Six-Speed Transmission complete kit

“We don’t include a torque converter in the transmission package because it is so important that you get the best one for your needs,” he says. “So we will help you determine the best torque converter for your vehicle and your driving habits then make sure you get that converter. For example, say you have a mild big block that you drive daily and also tow with occasionally. In that situation, I’d go with a mild 1,800 to 2,000 rpm stall speed converter. But if you have a hot rod with a small block, fewer cubic inches and a ‘lopey’ cam, then you’d want to consider one of our 10-inch converters – possibly a StreetFighter® or a Super StreetFighter™. Those will allow you to idle the engine while the transmission is in gear and also get the engine into its best rpm range a little bit quicker. We just feel it is really important to help you get the best torque converter for your application; we won’t throw a ‘one-size-fits-all’ converter in the box and call it a complete kit.”

As you can see, TCI® has a product that’s about to shake up the hobby. A six speed transmission that is completely self-contained (no bulky external overdrive unit to require lots of chassis modifications), fits easily into many different applications, can be installed and tuned without a degree in mechanical engineering and improves both performance and fuel efficiency with an affordable price isn’t something many performance enthusiasts thought they would see in their lifetimes. But even with all that, Poff says the 6x Six-Speed Transmission is something that must be experienced to believe.

“You won’t believe how much fun it is to drive,” he says. “When you put it in your car you will swear you just found another 100 horsepower—the change in gearing helps that much. I really believe this thing stands a chance of making four-speed automatics obsolete.”





As an extra testament to the quality of this performance transmission, TCI® now offers a limited lifetime warranty on the 6x Six-Speed. Check out the TCI® website for details.


Sources:
TCI® Automotive
151 Industrial Drive
Ashland, MS 38603

Toll Free: 888-776-9824
Read More About The 6x Six-Speed
6x Six-Speed FAQ's

For more information about the TCI® 6x Six-Speed Automatic Transmission or any other TCI® products, call 1-888-776-9824, or go to www.tciauto.com.