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    4/7 SWAP

    We showed you how to build a small-block engine that could make over 500 hp and 500 lb-ft of torque on 87-octane gas. It was a motor that could be driven just about every day with a hydraulic-roller cam and a good carburetor, making acquisition and maintenance almost nonexistent. Like many things we do in the engine world, the results we enjoyed—while good—just weren’t satisfying anymore. We wanted more.

    Read More »

    METALFLAKE: The Roth Way

    Spraying flake isn’t a black art; it’s simply a slightly different medium. It’s no tougher to spray than anything else, although you do have to be meticulous, pay attention to the details and resist the urge to rush. Plus, unless you have a spray booth, it doesn’t matter how well you seal off your chosen spraying area: This stuff will escape and get everywhere.

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    TEST AND TUNE

    A stroll through the pits at the local 1/8-mile dragstrip is always fun for us, as you’re likely to see any number of cars that use a full-tube chassis, fiberglass body and monstrous slicks to click off consistent 5-second elapsed 1/8-mile times. However, it’s far more entertaining to see a stock-appearing car hit those same numbers, and that’s exactly what Greg Corbin’s ’98 Trans Am is capable of doing.

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    From Four to More: A Modern Manual for Your Vintage Mustang

    With Keisler’s PerfectFit Five-Speed Transmission Upgrade, You Can Have it All

    Author

    Picture of Will Smith

    Will Smith

    Story & Photography

    From Four to Five: Why Upgrade Your Mustang Transmission?

    Decades ago, Ford made the jump from four-speed manual transmissions to five-speeds. Newer Cobras even feature six-speeds, so it’s natural that those who own earlier Mustangs with four-speed manuals now feel a little gear envy. Many people love the feel of having a manual transmission, but if you’re still using a four-speed, you’re missing out on a lot of performance and economy potential. Adding a transmission with additional gears places your gears closer together for better acceleration and gives you more gears to choose from for easier cruising. But which transmission is right for your Mustang? You need one that’s strong, smooth and capable of bolting to your engine, and it’s not easy to find all three attributes in the same gearbox.

    Meet Keisler Automotive Engineering

    If you’re considering swapping a five-speed manual into your early Mustang, you need to consider calling Keisler Automotive Engineering (865/609-8187). Located in Rockford, Tennessee, this company is an expert at adapting new manual transmissions to older cars. Although most of the company’s previous experience has been in GM and Mopar circles, Keisler is expanding into the Mustang market in a big way. In fact, when Gateway Classic Mustang heard what Keisler had available, Gateway knew it wanted one of these transmission conversion kits for its Eleanor clone that we featured in our June ’06 issue. The car was equipped with a four-speed T10 manual, and considering everything else that Gateway had built into this car, the transmission was sorely lacking.

    The Keisler PerfectFit Kit and Tremec TKO-600

    Keisler responded with a PerfectFit upgrade kit and a Tremec TKO-600 five-speed manual transmission. The TKO-600 is an incredibly stout piece. Unlike factory five-speeds, this one is made for performance and can handle 650 hp right out of the box. But Keisler doesn’t leave the transmissions alone. Keisler modifies them with a shifter location designed for your specific vehicle and includes a high-performance, short-throw shifter. The shift tower and tail shaft are designed to keep cutting of the floor to a minimum, and a T10-style bolt pattern means the transmission will bolt right up to your engine. But the PerfectFit kit includes much more, including a new crossmember, mount, driveshaft, speedo cable, pilot bearing, hardware and even a six-month warranty.

    Additional Components for a Seamless Swap

    Keisler also supplied Gateway with a clutch kit that included a new SPEC clutch disc, pressure plate and flywheel. Keisler included a new shift boot, arm and knob, too, as well as a hydraulic clutch kit with a clutch cylinder, reservoir and line. Additional parts, such as pedal assemblies, are available if your Mustang is an automatic and you want to make the swap.

    Installation with Gateway Classic Mustang

    We were present at Gateway Classic Mustang as Keisler and the GCM crew teamed up on the installation. Although they had a lot of manpower and expertise, you and a few friends should be able to perform the same installation in about a weekend. There are a few special tools involved, so when you call Keisler to ask what it recommends for your car, find out what you’ll need to install the kit as well. But with that said, follow along with GCM and Keisler to see how you can get more performance, fuel economy and fun out of your Mustang by upgrading to a Keisler five-speed transmission.

    1. Among the components included in the Keisler kit are a new Tremec TKO-600 transmission, balanced driveshaft, speedometer cable, speedo gear, crossmember, trans mount, pilot bearing and all the necessary hardware for the installation.
    2. The hydraulic clutch kit includes a new throw-out bearing, cylinder, reservoir, hydraulic line and more.
    3. Keisler specializes in complete transmission swaps, so it’s got everything you need for your conversion. The company can supply a new pedal assembly, bell housing, SPEC clutch, pressure plate, flywheel, shift arm, shift boot and shift knob. Buying everything you need in one kit will make your life much easier.
    4. The original four-speed was adequate for most driving, but there’s no question that the Keisler TKO five-speed will be a better choice.
    5. The old transmission won’t come out until the subframe connector brace is removed.
    6. After removing the brace, the next step was to unbolt the driveshaft and remove it from the car.
    7. Normally we’d tell you to put a transmission jack in place before removing the transmission crossmember and mount, but the GCM and Keisler guys needed a little wiggle room, so it’s not in place yet.
    8. The wiggle room was necessary to remove the original shifter, and the guys had enough muscle to hold up the transmission for that.
    9. Now it’s time for the transmission jack.
    10. It proved to be easier to unbolt the transmission from the bell housing and remove the transmission in this manner. You’ll need a long extension, and a swivel wouldn’t hurt.
    11. The starter and starter shield will be reused but must be removed for now.
    12. Now remove the bell housing.
    13. Keisler supplied replacements for the clutch, pressure plate and flywheel, so all the original components were removed from the car.
    14. Temporarily install the new bell housing and use a dial gauge indicator to check for run-out—the misalignment between the crankshaft and transmission input shaft caused by stacked tolerances. The run-out should measure 0.005 inch or less, and if you don’t have a dial indicator, Keisler can supply one.
    15. Use a torque wrench to install the new flywheel to the recommended settings.
    16. Before going any further, the Gateway crew used the Keisler-supplied template to locate a small area of material needed to remove from the transmission tunnel.
    17. A grinding wheel made quick work of this area.
    18. After cutting away this metal, GCM made sure to seal it so it would not rust the metal above.
    19. After the builders applied some black paint to the area, it was ready to go.
    20. Installing a clutch disc is just about impossible without an alignment tool, so make sure you have one before you get too deep in this project. Keisler supplies a tool with its clutch kits.
    21. The next step was to bolt up the rest of the clutch assembly.
    22. Before you can bolt up the transmission, you’ll need to measure the depth of the hydraulic throw-out bearing, as seen here.
    23. You’ll need to compare your previous measurement to the depth of the clutch fingers relative to the face of the bell housing (which you should only mock up at this point).
    24. Unlike removing the old transmission, the new one will be easier to install with the bell housing attached, so bolt these two items together.
    25-26. The builders are installing the hydraulic clutch line.
    25-26. The builders are installing the hydraulic clutch line.
    27. The bracket is held in place with another bracket inside the bell housing. Connect the clutch line to the throw-out bearing and bolt the brackets together.
    28. The Keisler transmission weighs about 100 lbs. If you have enough friends, you can lift it into place without using a tranny jack.
    29. After the TKO was in about the right spot, Gateway used a trans jack to support it while the Keisler guys installed the shifter. It’s easier to do so now rather than after the transmission is bolted in place.
    30. The rear of the engine had to come down a bit for the transmission to bolt up, so Gateway used a jack to raise the nose of the engine.
    31. Getting at the bell-housing bolts can be a little awkward, so you’ll need a big extension again.
    32. One major advantage of the Keisler kit is that the shifter will come through the exact same spot in the floor. You won’t have to cut any new holes or fill old ones. Just bolt up the shifter arm.
    33. The new Keisler-supplied driveshaft is balanced and features sealed U-joints for long life. Although Keisler has information on many models of car and engine combos, you should definitely take measurements to make sure you are supplied with one that is the correct size.
    34. It may be difficult to see in this shot, but bolt the transmission mount to the transmission.
    35. The new tranny mount uses one additional hole per side for extra support. Bolt it up using the stock holes and then mark the location of the new holes.
    36. Drill your new holes.
    37. Install the new bolts and tighten all four crossmember bolts.
    38. Secure the transmission mount to the crossmember.
    39. The new speedometer cable plugs in place easily.
    40. Reinstall the starter shield and starter.
    41. Unfortunately, cramped spaces under the hood make it just about impossible to install the hydraulic clutch cylinder and reservoir, so we’ll advise you to trust the Keisler instructions here.
    42. The new Keisler Tremec TKO-600 is now in place. Gateway let us take the car for a spin, and the entire assembly shifts quickly and smoothly—it’s a ball in this car. Don’t you want the same?

    EDITOR’S NOTE

    Keisler Automotive Engineering is now Silver Sport Transmissions (SST). SST continues to offer high-performance transmission solutions and remains a trusted source for PerfectFit™ kits and Tremec manual conversions for classic Mustangs and other vehicles.  For the most current products and support, please visit www.shiftsst.com to learn more.

    ARTICLE SOURCES

    Picture of Silver Sport Transmissions

    Silver Sport Transmissions

    2250 Stock Creek Blvd,
    Rockford, TN 37853

    (865) 609-8187

    FACEBOOK
    Picture of Gateway Classic Mustang

    Gateway Classic Mustang

    10461 N. Service Rd.
    Bourbon, MO 65441

    (573) 732-3541

    FACEBOOK
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