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When we decided to look into improving the front suspension on the Ford unibody compact cars, Brent remembered back to a ’65 Falcon sedan delivery he had back in the ’70s. After wearing out a set of F70 × 14 bias belted tires in just 7000 miles, he put the car on a lift to check the toe in. A quick measurement showed a toe out of 2"! So he naturally pulled the tie rods in, setting about 1/8" toe in, and set the car on the ground. Imagine his amazement at seeing it now toed in 2". After some head scratching, a call was made to Lew Parks, the local race car guru, who explained the facts of bumpsteer to Brent. As he likes to say, it took 30 years, but he finally fixed that Falcon! (and started a pretty involved journey in learning to design suspension.)

Way back in 1991, we were already making many variations of Mustang II based suspension, so that seemed like a natural way to go. A ’65 Falcon V8 wagon, similar to the Mustang, was borrowed and put in the shop for R&D. There are certain position of the spindle height, control arms position, rack & pinion height that must be preserved for the suspension to work correctly. It was quickly determined that with the rack height being limited by the front mounted oil pump, the rack could only goes just so high in the chassis. No matter what oil pan is used, even considering a dry sump system, the best you could do with stock MII spindles was raising the car 1" from stock ride height! Dropped spindles only give you a 1" drop, unless the coil springs are cut so much as to violate the suspension geometry. Look at the ads from Heidts for their MII IFS, and you’ll see that they came to the same conclusion. A couple grand for a new suspension without much drop seemed ridiculous!

Further, we quickly saw that the original subrail was too wide to clear the coil springs without a lot of cutting. Add to that the light sheetmetal used to from a subrail box never design to take the weight of the car. Ford designed the car to carry the weight up into the shock towers and then back to the firewall thru the braces. Now cut out what little strength the inner fender panels provide, and tell me what keeps the car form folding up like a jack knife? It is interesting that similar MII based kits for the very similar unibody ’62-67 Novas require a tubular brace from the frame rail to the firewall, but by some form of mechanical magic, builders of MII kits think the Mustang doesn’t. Has anyone considered how an already weak and improperly stressed subrail is affected by the rust we all fight in our Fords? All this structure was barely serviceable with small engines, skinny tires, and fresh, uncut metal!

So, we looked at a strut type suspension. It puts the stress into the unibody structure just as the original designers intended. Since nothing is cut, the car can easily be returned to stock. A nice 2-3" drop is achieved without cutting things up. Adjustable coilovers allow easy fine tuning of the ride height. The new suspension uses many well proven late model Ford parts for easy repair and bolts in so that the installer doesn’t have to be a fabricator. More precise rack and pinion is included, with power assist an easy option. And stock 11" disc brakes are standard, with the ’94-04 Mustang spindles accepting the endless upgrades in the aftermarket. A tilt column makes the steering hookup easier, and also easier to get behind the wheel.

The price is quite reasonable, aided by the use of many factory Ford parts. We see the same ads you do, listing power rack conversions for $2000, and struts with disc brakes and coilovers for $2200. That seems kinda high, totaling over $4000, or almost twice our kit, which includes the tilt column and steering U-joint parts, worth over $400 alone. And again, spending hundreds of dollars on parts like tubular control arms that just beef up a poor factory design doesn’t seem to us a logical approach. Now, we know that other people have other opinions, but based on 30 years building hot rod suspension and formal engineering training, we are committed to our design Strut IFS for the Ford Ponycars!

This entire line of Strut IFS kits for the Ford intermediate cars has been updated in 2009 to include several MAJOR improvements. A power rack & pinion from the 90-04 Escort is now used ,as it is heavier duty and easier to obtain than the earlier Escort item used before. That rack also has an angled input shaft, and is mounted in a way that allows a total of 2” more space for headers! Many rack & pinion conversions use special racks that will be hard to find and expensive to replace, while we use a very common unit. And we get an excellent turning radius, rather than the common loss of turning radius seen in many conversions.

You are not required to trim or cut the shock towers if you prefer to preserve the structure of your car. Since the McPherson Strut type suspension we use eliminates the upper control arms, you have the option of cutting the towers for header clearance if you prefer. The strut suspension lends itself very well to these cars, and feeds the suspension forces into the Unibody, just as the Ford engineers intended, with the spring on the upper control arm. We’re pretty well convinced that they would have used the strut type suspension as the original design if it had been developed as well as it is now!

A 5/16” plate main K member now mounts a true A frame lower control arm that eliminates the factory strut rods. That K member ties into the original engine mount and lower control arm mounts to add tremendous rigidity to the entire Unibody structure. As originally designed by Ford, the car has no real crossmembers from the one under the radiator all the way back to the seats! You will get excellent ground clearance, a much tighter feeling car, and handling on a par with the 94-04 Mustang donor car. Finally, your Mustang can drive as well as it looks!