Twist Machine's new Shrifter makes paddle shifter technolog an affordable reality for your g-machine.
For a long time hot rodders have had to make tough choices. One of these was choosing between a manual and automatic transmission. For the road course nothing beats rowing through the gears manually. It's sort of a Zen experience where man becomes one with machine. Not to mention that you are able to put yourself into the right gear at the right time. All is perfect in this world until you find yourself stuck in slow-moving traffic or at some cruising event. At those moments, when your right arm and left leg are slowly going numb, you wish you had an automatic. For the automatic trans guys, the slow stop-and-go traffic is a breeze, but on track day they are left out of one of the most enjoyable aspects, manual gear selection. Until now...
Visit any car dealership and you'll be hard pressed to find a new car that does not have an electronic transmission. And, thanks to those electronically-controlled transmissions, there's a pretty good chance that your new car will have some sort "manu-matic" feature that allows you to emulate a manual transmission without the delay inherent to pre-electronic "slush boxes." Everything from a new HEMI Magnum R/T to a Volkswagen Passat benefits from manu-matic shifting control. Chrysler calls their manual shifting function AutoStick while Porsche calls their design TipTronic. Regardless of the name, the technology is almost commonplace. So, why are hot rodders lagging behind?
Some would argue that the technology is unavailable in an older car. Well, guess what? It turns out that manu-matic functions have been hiding in aftermarket transmission controllers for many years. Those of you running TCI's T-Com system have a connector hanging off your harness that's marked "manual shift." The feature has just been sitting there, waiting for creative car guys to tap into the benefits. Other transmission controllers like Powertrain Control Solutions, Compushift and soon BigStuff3 also have manual-shift inputs. But, for ease of programming, we chose TCI's unit for this install. So one half of the puzzle has been in place for years, now all that was needed was just a way to control the shifts to take advantage of this modern manu-matic technology.
First, you need to understand how the modern transmissions like the 4L60E and 4L80E operate. Many people still refer to these tranies as "slush boxes" and figure that they operate in the same way as their old Turbo 350s and 400s. This is not the case. Even though the newer transmissions still have a mechanical lever, they are not a mechanical shift mechanism. Moving the lever merely activates electronic switches inside the transmission and adjusts the gear accordingly. A computer that selects the gear based on rpm, mph and throttle position controls this new breed of tranny. If the transmission is, in effect, controlled by electronic switches then couldn't you bypass the mechanical lever all together? In a word, yes.
Steve Chryssos had an automatic trans and he loved it, but he loved shifting too, so what to do? Steve and his friend, Frank Cerasuola, have been messing around with manu-matic shifting for years, but credit the initial concept of a hot rod manu-matic system to hot rod electronics guru John Meaney. Six-or-so years ago John had the foresight to include the manual-control option in his transmission controller design. Steve and Frank started with a TCI system and a couple of steering-wheel mounted buttons with coil cords wrapped around the steering column. The whole deal was very primitive. It wasn't pretty, but it worked. In fact, Popular Hot Rodding published pictures of their makeshift design way back in May 2003. As far as we know, this was the first published example of a "manu-matic" hot rod.
After seeing that this would work, Steve and Frank formed the company Twist Machine LLC and set out to perfect this electronic interface. Borrowing an idea from F1, they designed the Shrifter, a paddle shifter that could electronically control the first through fourth shifts in modern GM transmissions. The Shrifter unit bolts to the steering column and replaces the hub used with aftermarket steering wheels. The Shrifter has paddles at the 9 o'clock and 3 o'clock positions with the right paddle controlling upshifts and the left paddle controlling downshifts. When a paddle is pulled toward the wheel, it activates a switch, which sends a signal, wirelessly, to a control box. In essence it is really just three switches packaged in a very cool design. One switch for upshifts, one for downshifts and a separate switch to engage the system. Delay between the transmitter and receiver is a mere 0.125 seconds. Unfortunately, The Shrifter does not work with stock PCMs, so an aftermarket controller is a must. Another advantage is that you can turn the Shrifter off at any time, and your transmission will shift automatically like normal. Cool huh? The wireless design is very cool since it eliminates having to mess with running wires through your steering column. If you can replace a steering wheel then you can install the Shrifter, it's that easy.
The other part of this system is the computer that controls the transmission. A factory PCM does not offer much flexibility with programming and, while okay for stock applications, will not give you the control you need. For this duty an aftermarket transmission controller is required. TCI has been making a transmission controller for sometime now. The TCI T-Com has mainly been used by people who want the benefits of an electronic transmission in their computerless car. As mentioned, the T-Com has an input for the Shrifter so if you already have the TCI unit installed then the Shrifter is a simple plug-and-play install. The T-Com also has a laptop port that allows you to easily interface with the trans computer. You are able to set part-throttle shifts, wide-open throttle shifts, rpm levels and a host of other parameters. One other helpful tool is a virtual dashboard function, with data logging capabilities that let you monitor the operation of your transmission in order to fine tune it better.
 We ran the other wires up to the engine. The T-Com needs to know throttle-position so we tapped into the LS1 throttle-position sensor. For our LS1 install it was white to blue and red to grey... |  ...If you are doing this install on a carbureted engine then you will need to get a remote TPS mount from T-Com. Also, if you don't want to splice into your wires, TCI makes adaptor harnesses for the TPS and ones for use on applications where you have a distributor. |  Now for the fun part, and surprisingly the easy part. Here is the whole Shrifter system from Twist Machine: The Shrifter, optional adaptor, interface computer and mode switch. The Shrifter is wireless so no wires need to be run between the paddle-shifting hub and the computer, slick huh? |
 The fist step will be to remove your existing steering wheel and hub using a wheel puller. If you have a stock steering wheel you will need to get an aftermarket steering wheel that uses a hub system. The Shrifter fits '67-94 GM steering columns as well as custom columns from Ididit and Flaming River. Wheels supported include 9-bolt wheels by Budnik, Billet Specialties, LeCarra and Colorado Customs. An optional adaptor (PN 10091) is available if you want to a run 6-bolt steering wheel like those from Momo and Sparco. For a Grant steering wheel you will need the 5-bolt adaptor (PN 10090). |  After you have the old steering wheel removed, the Shrifter installs like any aftermarket steering wheel hub. It doesn't get much easier than this. This is also a good time to replace any broken or missing column parts like turn signal returns or ignition switches. |  In our case, the Shrifter would have hit the turn signal lever if we had put it on all the way. All we had to do was straighten out the billet lever by bending it a bit, and we were good to go. |
 A nine-bolt steering wheel, like the ones mentioned before, bolts directly to the Shrifter and does not require any adaptors. |  For my car I wanted a fully leather-wrapped steering wheel. In order to install a 6-bolt wheel we got the adaptor (PN 111232) from Twist Machine. This will let me install my slick new Momo Fighter steering wheel. Due to the design of the 5- and 6-bolt steering wheels, the adaptor does not really move the steering wheel closer to you. |  You will then need to install the wireless transmission interface. It needs to be located somewhere near the steering column. We mounted ours where the firewall meets the trans tunnel using that magic Velcro stuff. Then, I connected the unit to a switched 12v supply and a ground. In this location there is a clear path between the Shifter hub and the interface. Both the Shrifter hub and the wireless interface both have test lights on them so you can make sure the location is good. When you tap the right Shrifter lever toward you the green light will blink on the interface and the red light will blink on the Shrifter hub. When you tap the left Shrifter lever the red light will blink on the interface and the red light will blink on the Shrifter hub again. This way you're assured that the signal is strong enough. |
 Find a handy spot to mount your mode switch. This will allow you to turn the Shrifter off and let your car shift automatically or turn the system on and enjoy the fun of banging through the gears manually. It is important to note that if the system is on you must shift just like in a manual car. We mounted our switch in the center console. Connect this switch to a 12v source and to the wireless transmission interface. |  Now you simply need to plug the Shrifter wireless interface into the "manual shift" plug on the TCI T-Com. And that is that. All you need to do now is clean up all wires, zip-tie them up nice and neat and you are done. | |

Programing The T-Com
Like any computer, the T-Com needs programming. Some things have to be programmed in like tire size, transmission type and gear ratio. The best part about the software is that it allows you to take precise control of your transmission functions. You can control and alter the feel of the gearshift, the timing of the gearshift and the application of the lock-up in the torque converter. The T-Com software also allows you to have the transmission shift at Wide Open Throttle solely as a function of engine rpm, while it continues to follow shift curves based on road speed and throttle position during part-throttle driving. The software includes a dashboard function with data logging capabilities. This is very handy when it comes to fine tuning how and when your transmission shifts. When you are in the manu-matic mode the T-Com will automatically put you back into first gear if you come to a complete stop (rolling stops don't count). In addition, it will stop you from accidentally paddling into first gear at 90 mph. It won't keep you from hitting your rev-limiter if you forget to shift though, just like a manual transmission. Both TCI and Twist Machine were great when it came to technical questions. So far I love the system, I am able to enjoy driving in traffic and when the mood hits me I can paddle shift myself crazy through the gears, it is truly the best of both worlds.