Phobia #2: Will my headers fit the rack?
Selecting the right headers seems to be the really big issue with rack-and-pinion conversions. The reason is that the gear in the rack is towards the middle of the car rather than bolted to the frame. This means you have a driveshaft cutting across real estate that used to be taken up by the headers.
Headers that were designed for the original cars are designed to clear the original steering gear mounted to the frame. Late-model headers won't work because they hit the shock towers and dump in silly places.
If you want headers that fit your rack system, look no farther than JBA's mid-length headers. Having experienced header issues with past rack installs, we were pleased to see how easy it was to install the JBA units and have no clearance issues whatsoever with our small-block installation.
For our application, the midrange header (PN 1650, $500-$650, depending upon material) runs towards the back of the block before angling down, which helps it clear the input for the new rack. Traditional headers start angling down almost immediately, causing a conflict with the steering shaft that's angling towards the steering column. The fact that JBA offers ceramic coating and stainless versions of the mid-length design makes for an even easier decision when selecting headers.
Owners of manual-transmission cars may need to look at clearance issues with the linkage to the clutch, while those with big-block cars already know how much gf a pain headers can be even without changing the steering (you've probably already had to modify the headers to fit, haven't you?). Our advice is to move away from 40-year-old header designs and look for a new one that runs towards the rear of the engine compartment before turning down. JBA can help you select the right header for your project.
Phobia #3: Power-steering pump issues
Most modern rack systems that are used in these conversions are designed for front-wheel-drive cars. Because of this, the pressure that the system works at and the weight of the chassis-and in some cases, the weight load over the front wheels-can have a dramatic effect on the performance of a power steering system. Although it might seem tempting to run out and start making your own rack systems, there is a considerable amount of engineering involved in making these systems work properly for a big-motor/rear-wheel-drive car.
If you're thinking about using your original power-steering pump to save a buck, we'd like you to reconsider. The original Ford pumps are not designed for the correct pressure range on the new rack systems. Although Randall's and other manufacturers will allow you to use the original pump, they don't recommend it because the performance of the rack is reduced due to the mismatch. It's better to use the manufacturer-recommended pump to get the maximum performance from your new steering system.
Randall's offers a modern pump that doesn't require an external reservoir for operation, so it's less intrusive to your engine bay. The company can provide the new pump with a traditional V-belt pulley or a new serpentine pulley for 5.0 conversions. It also offers a complete line of brackets to fit the pump to the old or new beltdrive systems.
Depending on your application,...
Depending on your application, Randall's provides the correct conversion sleeve to suit. The angled sleeves are used on later suspensions for additional clearance; the straight version fits earlier models.
The old manual-steering system...
The old manual-steering system from our '70 Mustang convertible was removed, and we measured the length of the tie-rod system. We'll use this information for a base setting on the new steering system.
To get the correct length...
To get the correct length on the new system, the inner tie rod should be trimmed about 111/42 inches before assembly.
Mark the end of the tie rod...
Mark the end of the tie rod about 1 1/8 inch from the end.
The tie rods are soft enough...
The tie rods are soft enough to cut with a hacksaw, if needed. Clean the ends, and you're ready to go.