For heavy street cars it's often necessary to run more gear (numerically higher) than you would like. Using a shorter gear will definitely improve the way your car launches and how it runs overall, but the shorter gear will drastically affect the drivability.
Since the motor will be in the power band faster, it'll be harder to keep a handle on it while street driving. The biggest downfall, besides using more gas, is freeway driving. When the engine is spinning at about 3,500 rpm and the speedo only shows 60 mph, it makes one wonder if it is worth it.
One of the cures for these traits is an aftermarket offering from TCI. It's a 4L80-E overdrive transmission-the same automatic that comes in dualies. It is an electronically controlled unit that still uses a lock up converter. The 4L80-E has the same basic gearing as the Turbo 400, with a Fourth and Final "freeway" gear. The high point here is that you can set your own shift points using a laptop computer. Also, with the help of the Throttle Position Switch (TPS), you can set how, when, and how hard the kick down comes on. With the custom program supplied with the small control box, it's possible to do just about what ever you want with this transmission.
The donor car is 3,700 pounds of Camaro. It is powered by a small-block equipped with AFR aluminum heads and a street blower, and has clocked quarter-mile times of 11.50 at more than 120 mph. There has also been many sessions of track days at different road courses, and it's driven fairly consistently-even making a full pull on the Power Tour. With all these accomplishments, it's a perfect candidate for our latest adventure.
Follow along with us as we show how relatively easy the job is. After all was said and done, we were allowed a very short period of time to drive the Camaro. We had to keep in mind that the computer was not yet calibrated, but the new tranny felt great and had a solid shift. We could not play with it for very long, and now that it is back with its owner, we have heard that it's just awesome to drive along the interstate, as well as on the track.