1966 Ford Mustang - Perfect Fit Manual - PHR Project Car

Street Fighter
When was the last time you saw an automatic car smoke the manual drive competition on a road race circuit? Well, it probably was smoking from the overheated transmission fluid. It's no secret that manual transmissions dominate the road race and autocross venues and are also quite popular at the dragstrip. Our reason for the swap into our '66 Mustang is for all of the above, and the general fun-to-drive factor that comes with a clutch.

Project Street Fighter Mustang started out as an inauspicious '66 coupe whose body panels concealed a straight-six auto-driven drivetrain. The rest of the car was as stock as the powerplant. Over the months, we've been updating it. You may have caught the Chassisworks front and rear suspension overhaul and the big, bad Smeding 427 Windsor build. Keeping with the hard-core road race theme, we wanted to back the small-block with a manual transmission.

When it came time to choose a transmission, we wanted something modern that required minimal modification to the floor and other related components. We knew manual transmission swaps were something Keisler specialized in. They've got several options when it comes to GM, Ford, and Mopar conversions. In our particular case, we wanted something that would fit under the floor without modification. New to Keisler's lineup is their T45-RS Perfect Fit kit. Keisler has modified this late-model Mustang transmission to withstand more power and more abuse than the stockers. They also adapt the transmissions to use a Toploader bolt pattern to make it easy to adapt to standard bellhousings. If you're doing an automatic-to-manual swap, then Keisler supplies a bellhousing to use. We needed everything, and that's what our kit included. They also have T45-RS PerfectFit kits for popular GM models.

First to mate to the engine is a Ram billet steel SFI-approved flywheel. The clutch assembly also came with Keisler's new Pro Touring series clutch disc and pressure plate. This combination is aimed for street use, but is definitely capable of holding the power our Windsor puts out. It's a ceramic material disc that is good for 650 hp, well higher than the engine produces. The clutch is actuated by a hydraulic throw-out bearing. We wanted to use their hydraulic setup because of its compact design and modest pedal effort. The kit contains a Wilwood master cylinder with a remote reservoir that uses the factory clutch linkage hole that is on every Mustang, thanks to Keisler's billet firewall adapter. The transmission's modifications by Keisler makes it much more driver friendly because they've fixed some of the issues this model is notorious for, like the shifter popping out of gear when in reverse.

The transmission crossmember greatly improves the strength of the old Mustang's floor, while giving the tailshaft some place to rest. It's made of mild steel and powdercoated black for a clean look. The crossmember doesn't require floor modification to fit, but it does have two sets of bolt holes to improve rigidity across the tunnel. You will have to drill these holes out to match the crossmember's holes. There are two other places that need some modification, but they are extremely easy. The transmission tunnel has a support that hangs down about an 11/2 inches that needs trimming, and also the shifter opening needs to be adjusted. Keisler includes templates for all these cuts, so don't worry, there's no guessing. They also offer the option to keep the shifter hole in the same place, and to modify the engine mount holes to aim the transmission to the shifter hole. We're using Chassisworks motor mounts that were just too pretty to cut, and the amount to remove around the shifter was minor.

When it came for installation day, we needed to get the engine in to have something for the transmission to bolt to. It was nice to be able to align the clutch and install the pressure plate out of the car. We hadn't plunged the Windsor into the car yet, and were skeptical of how the headers would fit. We used Hooker (part number 6208-HKR), which unfortunately doesn't provide adequate floor clearance for the raised-port AFR heads. We knew that could be a possibility, and will be modifying them in the future to get the clearance we need, but they were a great starting point. With the engine and headers trapped in the engine bay, we were ready to start bolting the kit components on.

It would be misleading to say the installation was easy, and that a beginner could do it. It takes a good amount of trouble-shooting skills to complete a job this large on an older car. Being over 40 years old, these cars can warp, wear, and twist themselves out of spec, and each one is different. We had several variables leading into this project that needed to be sorted through. We advise you to have access to a lift, and that you have at least two days set aside to do it.

Keisler relies on a group of talented and reputable shops to refer their clients to for the installation. Close to our home base, Keisler referred us to their main distributor and installation center: D&P Classic Chevy of Huntington Beach, California. Don't let the name fool you, these guys can work on anything. Their shop housed mostly GM cars, but the Mustang wasn't treated as a foreigner. Owner Darryl Nance gave us his most Ford-friendly employee, Mike Swan, to help with the installation. Aside from a couple others who lent a hand in wrestling the engine into the engine bay, Mike and yours truly were able to do all the work on our own. D&P Classic Chevy opened its doors to the Mustang, and did a great job representing Keisler as one of their dealers and installers.

Clutch Assembly Prep and Install
If you're converting from an automatic to a manual, you will need to go through these steps. First, we bolted the flywheel up using blue (medium strength) Loctite. With the flywheel installed, it's easy to drive in the dowels using a brass drift. We don't all have fancy bearing driver tools, so this large socket works in its place to install the pilot bearing. With the pilot bearing installed, we push the clutch alignment tool through the clutch and into the pilot. This centers the clutch while we torque down the pressure plate. All of the parts here are included in the Keisler kit.

Pedal Installation
Our Mustang came with an automatic transmission, so it lacked a clutch pedal and had too wide of a brake pedal. The solution to this was quite simple. We ordered a clutch pedal from Keisler Engineering. When installing the pedal, we did have to remove the fresh air duct and operation lever for clearance.

The pin at the top of the clutch pedal replaces the pin that the brake pedal hinges on. This is extremely hard to photograph inside the car so we laid it on the ground to show how it works. Always lube the rotating surfaces. There's nothing worse than a squeaky clutch pedal! We used Royal Purple's Max-Tuff assembly lube for the job. We mimicked the shape of the clutch pedal to the brake by flipping it over. The original pedals are nearly straight on one edge and cut diagonally on the other. Mike of D&P cut the pedal with a cut-off wheel, then smoothed it up with a belt sander.

Driveshaft Measurement
All of Keisler's Perfect Fit kits come with a driveshaft. Unfortunately, they are unable to predict the future, so they require you to measure your specific combination. Not every '66 Mustang is the same, and most don't have their original rearends. You may remember the story we did on the Currie-built Chassisworks 9-inch that went into our Mustang. It has a different yoke than the original, so that needs to be taken into account. Keisler has specific directions for taking this measurement so they know how to build the driveshaft. They asked that we measure from the machined aluminum face of the transmission, to the flat edge of the rear end yoke. They also give a set of dimensions so you can determine your U-joint type. We came up with 52 inches using a 1330 U-joint. Just remember, measure twice and order once!