Modified Mustangs & FordsHow To Drivetrain
A Manual Transmission Manual
Take The Fifth
If the classic Ford you're driving still has the original transmission, then your freeway performance is probably suffering from "over rev" syndrome. Whether automatic or manual, the older transmissions found in our classics have a final drive ratio of 1:1. Even with a relatively tall 3.00 rear-axle gear ratio, you're engine is still spinning over three grand just to do the speed limit. If you're trying to keep up with your buddies who are equipped with overdrive you can forget about it. They'll just pull away from you like you're hauling lumber.
But if you've had enough of the right lane, and you're ready to turn your car into a freeway flyer, then listen up. No matter what kind of classic Ford you're driving, you can upgrade to a manual-shift overdrive gearbox. there are two different approaches for swapping the popular T-5 five-speed manual overdrive gearbox into your Total Performance Ford car. There are several different types of five- and even six-speed manual transmissions out there that we will look at, but the T-5 is by far the most popular. For price and performance, it's hard to beat this time tested and improved gearbox. Owners with original manual transmission cars can now utilize the bell housing, clutch, and clutch linkage they've already got. Using a special adapter plate and cross member from California Pony Cars, the T-5 will mate to the existing bell housing with a few minor adaptations.
About 85 percent of the classic Ford cars we're concerned with came equipped with automatic transmissions. That's a big percentage, and some of these enthusiasts are looking for a way to get both a stick shift and overdrive with one simple and reasonably priced conversion. This is now possible using a cable conversion kit. Just such a kit, complete with a modified pedal set, is available from several companies, including Mustang Depot and DB Performance Engineering. There's no need to replicate the OE lever and bellcrank linkage underhood. In this conversion, all T-5 hardware is used, including the bellhousing. Just a few modifications to the car are required.
We'll see how each installation method differs. We'll look in on some of the more important steps in each type of conversion. As we do, you'll be able to evaluate your own circumstances and then choose the conversion method that's right for your project. We'll also look at some T-5 alternatives.
How The Other Transmissions Compare
As we have already noted, the T-5 is the most popular of the manual overdrive transmissions. The latest incarnation is Ford part number M-7003-Z, which is rated in torque capacity at 330 lb-ft and costs $1,395. The '90-and-newer T-5 is rated to handle 300 lb-ft of torque, while the '85-'89 T-5s are rated to handle 265 lb-ft. All T-5 gearboxes installed in Mustangs from 1985 on are considered to be World Class T-5s. For those who want even more durability or an extra gear, there are more choices.