1993 Ford Mustang Engine And Transmission Installation - Stuffed Shrimp - PHR Project Car
The Quest For 9-Second E.T.'S Gets Closer As Project Fox Swallows Up A 775hp Big-Block Ford And A TH400 Trans.
From the March, 2010 issue of Popular Hot Rodding
By Stephen Kim
Photography by Stephen Kim
With a mammoth 532ci big-block hanging on a cherry picker, and a teeny-tiny 3,000-pound Mustang waiting to get stuffed, the entire scene looks terribly wrong. Like trying to fit Albert Einstein's brain into Paris Hilton's head, the very notion that the squeeze-fest that's about to ensue is even feasible seems entirely preposterous. On paper, we know darn well that this particular swap will work, as hot rodders have been transplanting 460-based big-blocks into Fox-body Mustangs for many, many years. Nonetheless, considering that Ford's 385-series big-block originally came equipped in gargantuan land yachts like Torinos and Continentals-cars that weigh between 1,000 and 2,000 pounds more and measure 3 to 5 feet longer than the Fox-that knee-jerk skepticism is difficult to escape. Optical illusions aside, once the wrenches started turning, the big-block dropped in real nice using nothing but off-the-shelf hardware. Aspiring to shoehorn as big of a motor as possible into as small of a car as possible is what this hobby's all about. It feels dirty. It feels good, and in this instance it's remarkably easy to pull off.
Over the past few months, our '93 Mustang project car has been getting prepped for 9-second battle with a custom 10-point chrome-moly rollcage, an Anthony Jones Engineering front suspension, a Competition Engineering rear suspension, and an 8.8-inch rearend fortified with Strange internals. What warrants all that chassis work is a 775hp big-block-built by the School of Automotive Machinists-that's been waiting for a new home since it was finished last spring. For the ultimate in durability in a compact package, the beastly mill has been matched up with a bulletproof TH400 trans from Phoenix transmissions. Now that the time has come to finally install the hybrid powertrain, the swap-specific parts we've been accumulating while building Project Fox are about to finally come in handy. They include a Moroso oil pan, Hooker headers, and an AJE trans crossmember and motor mounts all designed specifically for installing a 429/460 big-block Ford into a '79-93 Mustang chassis. Furthermore, the JW Performance bellhousing, flexplate, and crankshaft adapter leftover from our past trans build enables adapting the GM transmission to our Ford motor.
Despite the undeniable glory of dropping a carbureted big-block into a late-model chassis, we'd be remiss if we didn't acknowledge that swaps like this aren't legal in some parts of the country. In many states, the law frowns upon installing carbureted motors into cars equipped with EFI from the factory-regardless of the quantity of hydrocarbons they emit-so it's wise to check out potential legal ramification before considering a similar transplant. This obviously isn't a concern for track-only vehicles, but our Mustang will be driven to and from the dragstrip, which means it needs to be street legal. Fortunately, Project Fox hails from the Republic of Texas, which boasts more realistic vehicle regulations.
With that boring bit out of the way, it's time to get on with the show. Once again, we're indebted to the folks at Bill Buck Race Cars for letting us take over their shop for a day. Despite the fact that many of the swap-specific components came from several different manufacturers, we were pleasantly surprised by how seamlessly it all went together.
Back in the June 2009 issue,...
Back in the June 2009 issue, we covered the buildup of Project Fox's 532ci big-block. To recap, the combination uses a Scat rotating assembly, Kaase P-51 cylinder heads, a COMP 273/280-at-.050 solid-roller cam, an Edelbrock Victor intake manifold, and a Holley 1,150-cfm Dominator carb. For a total investment of $9,600, the big-block rips out 775 hp and 673 lb-ft on pump gas.
Although a Ford C6 is plenty...
Although a Ford C6 is plenty capable for our application, we opted for a GM TH400 for its superior efficiency, smaller external dimensions, and legendary durability. Built by Phoenix Transmissions, our PT400SX includes high-capacity clutch packs, a 300M billet steel input shaft, a five-pinion rear planetary, a billet clutch hub, a Kevlar band, and a 34-element sprag. Rated at 900 hp, it's a raging bargain at $1,645.
There's just something mischievously...
There's just something mischievously satisfying about tearing all the EFI-related components out of a late-model. The Mustang's stock 302 small-block and five-speed trans were pulled and sold off long ago. Since this car will see limited street duty, the A/C hardware, heater assembly, power steering, and power brakes were all chucked in the dumpster. After a quick pressure wash, the engine bay is ready for a new tenant.
It's tough to beat the ruggedness...
It's tough to beat the ruggedness of a motor plate, but we like the bolt-in simplicity of more traditional motor mounts. These AJE units are designed to position 429/460 Fords perfectly inside the Fox Mustang engine compartment. Furthermore, the modular nature of AJE's K-member means that it will also accommodate small-block Fords, big- and small-block Chevys, and LS1s by simply swapping out the mounts. To simplify installation, the mounts have elongated holes on the chassis side to make lining them up to the K-member much easier. Likewise, AJE offers crossmembers for Powerglide, TH350, TH400, C4, C6, and T56 transmissions. The mounts were included with our K-member kit (PN MU-40), and the crossmember (PN MU-7051) lists for $159.
During our engine build, we...
During our engine build, we ordered a Moroso rear sump oil pan (part No. 20620) designed for big-block swaps in Fox Mustangs. The front of the pan features a low-profile design to help clear standard-height steering racks, eliminating the need for costlier drop-rack configurations. It's proved leak-free thus far, and set us back $300.
|WHERE THE MONEY WENT
|AJE motor mounts
|AJE trans crossmember
|Strange master cylinder
|Strange proportioning valve
|Moroso oil pan
|Jegs throttle bracket
|Jegs throttle cable
|*Parts tallied in prior stories.
|THE COST SO FAR
|'93 notchback Mustang
|Sold old wheels, tires, engine, trans
|532 big-block Ford
|Phoenix TH400 trans
|Strange 8.8 rearend
|Comp Engineering rear suspension
|AJE front suspension
|Bill Buck custom 10-point cage
|Engine and trans install
Yet another testament to how...
Yet another testament to how popular these swaps have become, Hooker offers a set of 2.00-inch off-the-shelf headers (PN 6224HKR) for big-block junkies for $500. They feature robust 18-gauge construction, thick 5/16-inch flanges, 31-inch-long primaries, and 3.5-inch collectors. While the primaries are a tad small for our application, sacrificing a few ponies instead of dishing out $1,500 for a set of custom tubes is well worth the trade-off.
Cranking up an 11.0:1 big-block...
Cranking up an 11.0:1 big-block takes lots of juice, so TCI set us up with one of their extreme racing starters (PN 351600). It boasts a 3.73:1 reduction ratio, and dishes out 3 hp. At 11.5 pounds, it's lighter than a comparable stock unit, and more than capable of handling 500-plus cubic-inch motors with compression ratios of 11.5:1 and greater.
Big cams don't make much vacuum,...
Big cams don't make much vacuum, so the stock power brakes were ditched and converted to manual using a 1.125-inch bore Strange master cylinder (PN B3359). The coefficient of friction on a drag car's tires can vary significantly from front to rear, so it's always a good idea to plumb an adjustable proportioning valve (PN B3369) into place.
NHRA rules require an SFI-approved...
NHRA rules require an SFI-approved harmonic balancer for all cars running 10.99 and quicker in the quarter-mile. Right before the motor installation, we realized that we specified the wrong non-SFI balancer with our Scat rotating assembly during our engine build. A quick call to Professional Products set us straight, as they swapped it out for one of its SFI-approved PowerForce Plus units (PN 90008), which lists for $176.
Although the motor mounts...
Although the motor mounts are solid steel, they slide over urethane bushings on the K-member to provide a firm yet vibration-free foundation. The mounting location is triangulated on the K-member for superior strength, and has proven durable enough to survive in 7-second drag machines.
Due to the tight clearance...
Due to the tight clearance between the bellhousing and firewall, it's easiest to install the motor and trans one at a time. This allows dropping the engine right in without any drama. There's a surprising amount of space between the valve covers and shock towers, and with the exception of the number eight cylinder, spark plug access is very good. That said, the carburetor protrudes slightly above the hood line, and based on some quick measurements, a four- to six-inch cowl-induction hood will be necessary in order to run an air cleaner.
To eliminate the need to run...
To eliminate the need to run separate throttle and return spring brackets, Jegs offers this slick billet piece for Dominator carbs that combine both into one unit (PN 15237). It features adjustable mounts that enable fine-tuning spring and cable tension. Since the stock throttle cable was too short, it was replaced with a 24-inch unit (PN 157000) also from Jegs.
It wasn't just our 532's big...
It wasn't just our 532's big cam that necessitated the switch to manual brakes, as the bulky stock power booster stands no chance of clearing the driver-side valve cover. The Strange master cylinder mounts on a custom aluminum bracket made by Bill Buck.
With the motor in position,...
With the motor in position, it's quite obvious how well everything fits together. The Moroso oil pan clears the Unisteer steering rack with room to spare. The space freed up by the tubular design of the AJE K-member makes accessing the motor mount bolts for engine removal-and coilovers for suspensions tweaks-very easy.
The JW bellhousing adapts...
The JW bellhousing adapts the GM TH400 to a big-block Ford, but it retains the use of a Ford starter. The TCI unit is roughly 30 percent smaller than stock, and fits beautifully between the K-frame and oil pan.
In addition to the bellhousing...
In addition to the bellhousing itself, adapting a GM trans to a Ford motor also requires a swap-specific flexplate and crank adapter. The JW flexplate is essentially a Ford design that has been drilled for a three-flange TH400 torque converter. Since the GM torque converter snout is larger than that of a Ford transmission, JW includes an aluminum adapter that fits inside the crank flange. This ensures that the GM converter will center properly on the crankshaft.
Before stabbing it into the...
Before stabbing it into the trans, it's good practice to pour some trans fluid into the torque converter to pre-lube the moving parts. This will prevent seizure upon initial startup. Conventional-grade fluid won't cut it in the high-heat environment of a drag car, so we opted for some synthetic Royal Purple Max ATF. It boasts a lower coefficient of friction, greater film strength, and enhanced oxidation resistance compared to conventional trans fluids for a dramatic reduction in heat.
Before bolting the transmission...
Before bolting the transmission to the motor, it's essential to check for proper clearance between the torque converter and flexplate. After making sure that the converter is fully seated into the input shaft, and after test-fitting the trans on the motor, there should be a 1/8- to 3/16-inch gap between the flexplate and the converter mounting pads. Since the converter expands as it heats up, too small of a gap will place undue stress on the transmission pump and crankshaft thrust bearing. If the gap is too tight, an easy fix is machining material off of the converter pads, or shimming the bellhousing away from the back of the motor. If the gap is too large, washers can be installed between the converter pads and the flexplate. Per the recommendation of Phoenix Transmissions, we set the gap at 1/8 inch.
The tight confines of the...
The tight confines of the Mustang's firewall and trans tunnel makes reaching the top bellhousing bolts a challenge, but the trans tucked into the body very nicely. As with the motor mounts, the AJE trans crossmember has rubber isolators built into the chassis side. This eliminates the need for an actual trans mount, as the crossmember bolts directly to the transmission tailshaft.
The Hooker headers were designed...
The Hooker headers were designed to work with a stock K-frame, so the additional space provided by the AJE unit makes the install process go much more smoothly. On the driver side, the number six and number eight primaries are removable slip-fit tubes that simplify the installation process. Likewise, the number one and number two primaries on the passenger-side header are removable as well. After bolting the header/collector assemblies in from the bottom, the removable primaries went in easily from the top.