If you combine the rock-crushing transmissions that Hughes can build and add a bulletproof Gear Vendors Under/ Overdrive unit, not even Kryptonite can break this killer combination. Now that you are familiar with what Hughes Performance has to offer, let's take a look at what advantages a Gear Vendors unit can add. A Gear Vendors unit essentially splits your transmission's gears. With this overdrive unit attached to an automatic three-speed, such as this T-400, you now have a six-speed transmission. Virtually all three-speed automatics have the same ratios within a few hundredths (2.5 First, 1.5 Second, 1.0 High). This means your transmission takes 2.5 engine revs to turn the driveshaft once in First gear, 1.5 in Second, and is direct-drive 1:1 in High gear. Gears are multipliers of torque, and since the math of horsepower is torque x rpm 5,252 = hp, then putting a 2.0 gear between First and Second is going to keep the torque multiplication and engine rpm high, which means more horsepower gets to the rear wheels. If we can then put a 1.2 gear between Second and Third, and an overdrive gear beyond Third, we have a close-ratio six-speed overdrive trans with four underdrive power gears, a direct-drive High gear, and an overdrive cruise gear. Thus, Gear Vendor's trademark Under/ Overdrive can be used to double the underdrive performance ratios and provide overdrive cruising economies. Neat huh? Let's take a look at how easy this killer combination can come together