Poor Man’s Jerico

Our Mustang’s worn-out,...        read full caption Our Mustang’s worn-out, hard-to-shift T5 was costing us so much consistency and speed at the dragstrip that something had to be done. A Jerico crash box would have been ultimate, but for a fraction of the cost we installed a Liberty’s Pro Shifted Toploader in place of the grenade waiting to happen.

The Toploader we scored, a...        read full caption The Toploader we scored, a wide-ratio four-speed with a 2.78:1 First gear originally out of a ’68 390 GT Mustang, had already been Pro Shifted by a previous owner, who used it in an early Mustang. Along the way its 11/16-inch input shaft had been swapped out for a beefier aftermarket 13/8-inch input as used on factory 427 and 428 big-blocks. The Pro Shifting process involves milling or grinding the face teeth off the factory gears and replacing them with the Pro Shift rings (arrow), which are welded by a special process to the gear. Unfortunately, the big input shaft’s larger throwout bearing won’t work with a Fox Mustang’s cable-operated linkage setup, and swapping to a hydraulic throwout would be grossly complicated and expensive. An easier solution was to get a used small input shaft from David Kee Toploaders and send it off to Liberty’s to be Pro Shifted.

The NHRA requires all manual...        read full caption The NHRA requires all manual trans cars running quicker than 11.99 to have an explosion-proof bellhousing, but frankly, it was scary dumping the clutch at 5 grand in a 12-second car with a cast-aluminum bellhousing simply because we like having two feet. We chose this Lakewood unit that’s designed specifically for installing a Toploader in a Fox Mustang because it has provisions for the factory clutch cable and linkage. Bellhousing alignment is critical when installing any aftermarket scattershield, and it’s even a good idea to check it with the factory housing. We checked the Lakewood bell using a dial indicator mounted to the flywheel with the clutch removed and found it to be nearly perfectly aligned with the centerline of the crank. Lakewood recommends alignment within +/- 0.005 inch to avoid any problems with input shaft binding.

The Lakewood 1/4-inch–thick...        read full caption The Lakewood 1/4-inch–thick block-saver plate bolts between the block and the scattershield to keep pieces of shredded clutch or flywheel contained in the event of an explosion; it also protects the cylinder block. The plate is bolted to the scattershield with Grade 8 hardware, but two of the bolts fit into the recess at the back of the block with no way to get a wrench on them. We had the heads tack-welded to the block plate to make assembly easier (arrows).

A factory cast-iron flywheel...        read full caption A factory cast-iron flywheel is an accident waiting to happen in a high-revving drag car. An SFI-approved billet-steel flywheel is not only good insurance, it’s also required by the NHRA for cars running 11.99 or quicker, which our Mustang would be capable of if we could just learn to drive or get it to hook. The Centerforce billet flywheel we used incorporates a 50-ounce imbalance compatible with 1981-and-later 5.0L Ford engines. Centerforce recommends breaking in a new flywheel by having it resurfaced or sandblasted to help the clutch seat.

The last time we had the Mustang...        read full caption The last time we had the Mustang at the track, we finally fried the stock clutch, which surprisingly survived dozens of 5,000-plus rpm launches on sticky Mickey Thompson ET Street drag tires. It was time to step up to a clutch that could handle not only the naturally aspirated power we’re making, but survive the stout nitrous shots we’ve got in store. Centerforce claims its Dual Friction clutch and pressure plate should be good to at least 700 hp, which is more than we’ve got in store for it.

Most people throw away the...        read full caption Most people throw away the pressure plate–locating dowel pins the first time they have a flywheel resurfaced, but Centerforce tells us the dowel pins (arrows) are really every bit as important as the pressure plate bolts in keeping the clutch and flywheel together. New dowels are supplied with every Centerforce flywheel, so use them.

A brutal trans deserves a...        read full caption A brutal trans deserves a brutal shifter, and the best H-pattern drag-racing shifter you can get is Hurst’s legendary Super Shifter 3. The shifter body is mounted high on the tailhousing with reinforced straight-throw linkage rods that bolt directly to the shift-fork arms for positive, slop-free shifts. The no-compromise design means there’s no way it will fit into a stock console, and floor or tunnel mods will be necessary on most cars, but the reward is virtual elimination of missed shifts. It also incorporates a foolproof reverse lockout, which is required in some racing classes. Since these tuna cans are made of sheetmetal you can cut with tin snips, it was no problem for the Sawzall. We didn’t really need to make the long horizontal slice (arrow), but we cut the hole with the trans already installed, so we had no access for a big hammer to pound out clearance for the rods in the tunnel.

Also functional but far from...        read full caption Also functional but far from aesthetically pleasing is our fabricated aluminum trans tunnel cover, which we cut with tin snips from a $2.89 sheet of 0.040-inch aluminum and screwed to the tunnel with sheetmetal screws. But with carpet and a new Hurst Super Boot covering the opening, it practically looks factory.

Even though the Toploader’s...        read full caption Even though the Toploader’s 2.78:1 First gear gives us less mechanical advantage off the line than the T5’s 3.35:1 First gear, we still had a problem spinning the tires on the line when we tested at Los Angeles County Raceway. Maybe it’s time for new tires, but even though our 60-foot short times fell from the mid 1.70-second range into the dismal 1.85-1.90s, the car actually ran just as quick and slightly faster than it ever had. We posted a 12.64 at 110.5 mph with the Toploader compared to a previous best 12.61 at 108.5 before the swap. The traction problem cost us some e.t. for sure, but we more than made up the difference by finally being able to power-shift the car. With new tires and better conditions, it should run low 12s as is, but hopefully the next time you see us, we’ll be deep in the 11s on nitrous.

The only “engineering”...        read full caption The only “engineering” we had to do in the whole swap was to figure out a way to mount the transmission crossmember since the mounting pad location on the Toploader is about 2 inches farther forward than the T5’s. The simple solution is to cut the tack welds that hold the crossmember to the bushing barrels, slide it forward, and bolt it back up. This trick also works for installing a C4 automatic, which has the same mounting dimensions as a vintage Toploader. The crossmember doesn’t really need to be rewelded since it can’t really go anywhere.

The grass is always greener on the other side of the fence. If you run an automatic, you envy the stick guys who don’t need to hassle with the aggravation and expense of finding a “magic” converter that makes everything click. When you run a stick, you dream about the easy-on-parts, easy-to-drive consistency of an automatic.

When we put together our ’86 Mustang drag car project, we envisioned the macho factor of a stick from the get-go, and up to this point we’ve been using a fresh-from-the-junkyard factory T5 five-speed that cost 75 bucks. We’ve even been making do with a used stock clutch and flywheel, and it’s all been good enough to get the car into the mid-12s. But pass-to-pass consistency has been miserable mainly due to the clapped-out transmission’s propensity to miss shifts despite the precision B&M Ripper shifter we installed. The car launches hard on Mickey Thompson ET Streets with the T5’s 3.35:1 First gear combined with 4.10:1 rear gears, but the weak-link trans was a ticking time-bomb. We’ve been warned against power-shifting any stock T5, especially with the 400 hp we have on tap from our naturally aspirated 302, and given our plans to eventually add a 150hp nitrous shot, we knew it wouldn’t last more than a few passes on the bottle.

Of the several possible solutions to this dilemma, the least attractive was to bite the bullet and swap in an automatic. The upside of that would be a virtual guarantee of faster e.t.’s, since we’re no Ronny Sox in the shifting department. The downside would be feeling like we gave up too soon. Manual trans alternatives included a stronger overdrive, such as a Tremec TKO, which is a virtual bolt-in to a late-model Mustang, but is pricey at about $1,200, and we had absolutely no need for Overdrive in a dedicated drag car. So what’s the best solution? How about a Liberty’s Pro Shifted four-speed Toploader? Betcha didn’t see that one coming unless you read our “Stick-Shifts for Drag Racing” article in the Apr. ’02 issue, where we gave away the answer. The decision was made even easier when we were able to trade some parts with a friend for a cast-iron Toploader that had already been Pro-Shifted and came with a Hurst Super Shifter.

The basic concept behind a Pro-Shifted trans is elimination of the synchronizer mechanisms in the transmission to allow quicker shifts. Back in the glory days, drag racers built their own “slick-shifted” crash boxes by grinding off the engagement-face teeth on the gears and removing the brass blocker rings . Liberty’s process takes this a step further by replacing the face teeth entirely with components of their own design along with special sliders.

Given its non-synchronized design, a Pro-Shifted crash box isn’t too practical for everyday street use, but its fast-shifting performance combined with the inherent strength of the Ford iron-case Toploader design makes it an excellent alternative for the drag racer on a budget. For well under $1,000, even less if you don’t need a total rebuild while it’s apart, you too can have your transmission Pro-Shifted. Liberty’s Gears offers Pro-Shift components for most popular manual trannies, including Muncies, Super T10s, T5s, Mopar A-833s, and even the aforementioned Tremec. Prices start at $65 per gear, plus the cost of a rebuild, which is usually a good idea anyway. With the swap completed, we couldn’t wait to get to the track, and we weren’t disappointed with the results. This thing shrugs off brutal power-shifts like water off a duck’s back, and driving the car is a manly experience. Yank the stick in the direction of a gear and it bangs into gear with authority. Way cool.

So follow along as we swap this bulletproof badboy into our Mustang and bang-shift with glee at the track. At the fraction of the cost of a Jerico, all it took was a Sawzall.