Modern Muscle with a 5-Speed Manual Install

Installing modern manual Mopar muscle with Keisler five-speed upgrade

By Randy Bolig

Photography by Muscle Car Restorations

Making your Mopar a more "modern" style vehicle does not mean you haveto add 20-inch wheels, and/or drastically change the appearance of yourcar. We realize that your interest in muscle cars leans toward the stocklooking cars. But, does that mean you can't upgrade your car to handleand perform like a true 21st-century ride? Mopars are a hot commoditythese days, and more and more older Mopars are being modified toresemble a stock appearance than ever. It sounds strange that we say,"modified to resemble stock", but it's true. The classic look of thesecars, matched with new technology is a terrific combination. But, how isa balance achieved? Car owners are taking the necessary steps to retainthe timeless looks of a classic Mopar, but are updating, to make thatclassic drive similar to, or better than, a much later model.

But driving a vintage muscle car with the original four speed and steepgears at sustained high speeds on the interstates, quickly bringsseveral problems to light. The high rpm you experience with an older,non-overdriven transmission causes driver fatigue and poor fuel economy,and it contributes to reduce engine life. If you swap rear end gears, ora complete differential, to a long-legged (low-numerical) setup,acceleration is severely sacrificed.

So, what's a guy to do? Enter Keisler Automotive Engineering and theirlineup of five- and six-speed transmission installation systems.Keisler's kits are based on new Tremec five-speeds and six-speedtransmissions. These transmissions have large diameter and widthchrome-moly steel gears, quiet and efficient tapered roller bearings,all chrome-moly steel shafts, short throw internal shifters, and thanksto a pressure die-cast alloy ribbed case, a trim weight of just99-pounds for the five-speed, and 138-pounds for the six-speed.Keisler's kits are custom-engineered to fit a specific application, andthe kits are shipped with all necessary installation parts, including alightweight balanced chrome-moly driveshaft.

The advantages of late-model transmissions are, you get fasteracceleration in first gear with either a 2.97:1 or 2.66:1 low gear forgreat around-town drivability, and spine-tingling acceleration at thestab of the throttle. You reap the highway benefits of a low rpm,overdrive fifth, and sixth gears--gearing that will drop the rpm levelsat an interstate-friendly 75-80 m.p.h. to below what was previouslyturned at a meager 55-m.p.h. No old Mopar has ever been accused of beinga fuel miser, but in this day of premium unleaded nudging $2.50 pergallon, every increased mile per gallon counts.

We think there are some very good reasons to consider converting from anearly-model stock trans, either four-speed or automatic, to one ofKeisler's Tremec five- or six-speeds, so, let's see what it actuallytakes to make the switch.

Our Thoughts

If plan on driving your muscle car, be it a Mopar, Ford, or Chevrolet,the Keisler five-and six-speed transmission conversion is probably oneof the best upgrades you can make. Now, we don't want to blow smoke upanyone's you-know-what, so this kit will involve a fair amount of workto install. Do not let that deter you from purchasing this kit. KeislerAutomotive goes to great lengths, to make the kit as complete aspossible. If you can follow directions, and have a mediocre amount ofmechanical aptitude, this can be accomplished in a couple days time. Ifyou have more than a mediocre amount of mechanical ability, the timewill be shortened. For those of you that still feel it is above yourgrasp, Keisler can even schedule your car into their shop, and do theinstall for you. So, what are you waiting for?