Subscribe to the Free

Easy IFS Upgrade

RB's bolt in mustang II IFS for '49 to '54 Chevys

Bill Buxton Aug 12, 2002

Some owners like their projects to sit lower in the back than the front. Others like a slight rake. But, no matter where a custom's rear needs to sit, the front will always need to come down a whole bunch.

One way for '49-54 Chevy owners to accomplish this is to use a bolt-in front suspension mounting kit from RB's Obsolete Automotive, Inc. These kits get the front down while improving the ride, steering effort, handling, and breaking. No buckboard rides from cut coils today. These kits provide highway proven dependability and strength with proper suspension geometry for good handling.

To do this, RB's front suspension kits are designed to mount popular Mustang II suspension components featuring power rack-and-pinion steering and disc brakes. And, these kits accomplish the lowering job at the front of the car without using expensive dropped spindles.

These photos were shot at Kimbridge Automotive in Clearview, Washington. Gary Becktold and his crew were installing a complete RB's suspension package on this '53 Chevy hardtop. The body was done but the original chassis had not been touched. The owner wanted to use an RB's kit because it is easy to install and it works well with RB's rear suspension, power brakes, motor mounts, and trans crossmember kit.

The kit consists of the Front Crossmember, right & left Upper Spring Pocket/Upper Control Arm Mounting "Hats," right and left Strut Rod Brackets, Mounting Hole Template, and the necessary nuts and bolts to mount the components to your frame.

Installation of the kit required the usual hand tools. We used a grinding disk, a center punch, and drill motor with an assortment of drill bits to remove the rivet heads and to drill the holes to bolt the components to the frame. We also needed several clamps for attaching the template, and several wrenches for installing the components in the kit. Since we had to bend our strut rod we also needed access to an acetylene torch.

As you will see, there are no high end tools and no difficult procedures to follow. It's the kind of project that most hobbyists, with basic mechanical skills, can accomplish in their own garage. If you're a do-it-yourselfer, this is good news.


This is what we started with. A nice looking body on an original frame and drivetrain. The Chevy already had several coils cut from the springs. But, we would make it sit lower and ride better.

The straight six will be replaced with a new V-8. Motor mounts designed by RB's specifically for their frontend will be used.

The kit consists of the Front Crossmember, right & left upper spring pocket/upper control arm mounting "hats", right and left strut rod brackets, mounting hole template, and the necessary nuts and bolts to mount the components to your frame.

The first step was to pull the sheetmetal and radiator off the frame. The front fenders, inner fender panels, radiator support, and grille are removed as a unit. We enlisted Terry Portch, left, and Shawn Fitzpatrick to do the muscle work.

Once the sheetmetal was off, the engine and transmission could be removed, followed by the front suspension and crossmember, motor mounts, steering column and box, brake lines, and miscellaneous brackets.

This photo shows the front of the frame and suspension after the engine has been removed. Before removing the suspension, we placed jackstands under the frame at the firewall to support the car.

The original front suspension crossmember is simply unbolted from the frame.

The brackets that were riveted to the frame were removed by drilling out the rivet heads. We center punched the rivet heads before drilling them out. Centering the hole makes the job easier.

Drilling out the rivet heads is cleaner than using a "hot wrench."

The frame is ready for the new suspension crossmember. We cleaned up the frame and checked for cracks. In our case the frame was in good condition. If we had found any cracks or other damage, we would have repaired them before installing the front suspension crossmember. We also made sure the frame was square and sitting level.

To install the crossmember we used the template included in the kit to easily determine where the crossmember and strut rod mounting bolt holes need to be drilled in the frame. The template follows the bottom of the frame.

We clamped the template to the bottom of the right-hand framerail. The front of the template butts up to the back of the radiator crossmember, upper right, and the template follows the curvature of the frame back to the firewall. Proper positioning is very important.

Shawn uses the template to locate the mounting bolt holes, he center punched the frame to make sure the drill stayed properly positioned. We repeated this procedure for the left side framerail, using the same template, only flipping it over.

Since Shawn was drilling up, it was easier to drill a small pilot hole in the frame first.

With the pilot holes drilled, the larger 1/2-inch holes were drilled from the top of the frame.

With the holes drilled, we could install the upper control arm/spring pocket hats. These slip down over the frame and are mounted above the crossmember. As we slipped the studs through the holes we drilled in the frame, we took care not to damage the threads on the studs.

Gary Becktold, left, and Shawn positioned the front crossmember under the hats and slipped the crossmember's mounting flange holes over the studs in the hats that extend through the frame, sandwiching the frame in between the crossmember and hats.

We installed the hat stud nuts and washers, and wrenched them tight.

With the crossmember and hats installed, we attached the strut rod mounting bracket to the frame, behind the crossmember, using the remaining holes we had drilled in the frame.

This is the finished installation on the right side of the frame. Now we'll remove the crossmember for final clean up and painting before mounting our Mustang II components.

Here is the completed crossmember installation from the right side.

The completed crossmember installation from the driver's side.

With the front suspension crossmember kit installed, we assembled the suspension components. This kit will accept stock Pinto/Mustang II components or you can use most aftermarket suspension components. This photo shows the kit and associated Mustang II suspension components.

The rack mounts to the front of the crossmember. The tie rods correctly match the length of the lower control arm. The optional sway bar bolts to the left and right framerails, just above and slightly ahead of the steering rack.

The two rubber donuts allow the strut rod to rock in the strut rod bracket as the suspension moves up and down.

The optional sway bar mounts to a bracket attached to the lower control arm. Since these cars are heavier than the Mustang II you should seriously consider installing larger disc brakes. We used an 11-inch rotor kit sold by RB's.

If you are using a stock strut rod, depending on the donor car, you may need to slightly straighten the strut rod to fit this application. A template, included in the kit, shows the correct angle for the strut rod. Our strut rod, on top was one of those. It had a sharper bend than the template below it. We needed to remove some of the bend so that when it's bolted to the lower control arm, the rod points toward the strut rod bracket on the frame.

We used a torch to heat the strut rod in the bend near the base where it attaches to the lower control arm. We got it just hot enough to bend without stretching.

When the strut rod was hot enough, we put it in a vice to straighten it just enough to match the template.

The bend in the strut rod now matches the template.

This photo shows the rack shaft pointing toward the steering idler needed with the double steering shaft system used with this application. The front steering shaft goes under the bolt-on motor mounts attached to the driver's side hat.

The motor sits further back than it does in the Mustang IIs. Therefore, the weight of the motor is shifted somewhat to the rear springs and a lighter front spring is usually needed depending on the motor used. We used a 500 pound rated spring. This is the finished front suspension with the optional bolt-in sway bar and transmission K-mount. After installing the front crossmember, the guys at Kimbridge decided to remove the body to make it easier to paint the whole frame--nice but not necessary.

With the suspension installed and painted, it was time to reinstall the front sheetmetal. The inner fender panels needed to be trimmed to clear the upper A-arms. Using the core support crossmember as a reference point, we determined where the inner fender panels needed to be trimmed on each side and used a Sawsall to remove the necessary metal. The driver's side inner fender panel has been trimmed and is ready to reinstall.

The sheetmetal goes back on, just like it came off. Two people make the job much easier.

Note that the inner fender panel was trimmed just enough to allow adequate suspension travel.

There is plenty of access for aligning the frontend. After a few hundred miles, we'll inspect the installation and check all bolts to make sure they are tight.


Connect With Us

Get Latest News and Articles. Newsletter Sign Up

sponsored links

subscribe to the magazine

get digital get print