Hot Rod Crossmember Suspension Upgrades - The X Factor

The location of the 2x1-inch cross tube supplied with the crossmember kit is 55 1/2 inches from the centerline of the spring pin hole to the front edge of the cross tube. This location is important for the correct location in the brake pedal assembly if you choose this option. I measured back from the straight edge clamped above the spring pin hole and marked the framerails using another straight edge.

The forward edge of the cross tube proved to be exactly in line with the rear edge of the second pair of body mounting holes (arrow), the first pair being at the cowl. The cross tube will slide forward and wedge into place at this location. However, I elected to move the cross tube, and thus the whole Super X, rearward by 1 1/2 inches in order to align the rearmost weld of the crossmember side 'rails with the kick-up of the chassis. This was for appearance, the fact that I'll likely mount the body further back than a stock Model A to gain some extra engine compartment room, and to gain a little extra clearance for the transmission. As I probably won't use the brake master cylinder bracket (ground clearance would be an issue with the Z'd frame) this won't be a problem, though the cross tube now had a slight gap at each end.

With three pieces of box section laid across the chassis, and a flat plate with a 6x2-inch box to support the center spacer plate, I could lay the crossmember side 'rails in place above the frame to mark them for trimming. They are supplied uncut owing to variations in frame widths. This way they can be trimmed to fit stock or aftermarket frames.

Dagel's instructions suggest cutting a length of 6x2-inch box section to a precise 8-inch length and using it to space the side 'rails apart, but I opted to use the center spacer plate for this, raising it halfway up the side 'rails on a shorter length of box section that I had in my scrap metal bin.

Using the center spacer plate ensured the central gap was exactly 8 inches front and rear.

With every measurement double-checked, and the central gap between the side 'rails exactly at 8 inches, I marked the ends of the side 'rails for cutting to fit between the main chassis 'rails.

With all four ends trimmed, the cross tube was placed through the holes in the side 'rails and the assembly lowered between the main 'rails. I clamped it fore and aft to the box section placed across the chassis to ensure the top of the crossmember was level with the top of the 'rails. Once again the central spacer plate was used to maintain the 8-inch central gap, placed back on the 6x2 box section, which now sat on the flat plate clamped to the bottom of the 'rails.

A close up of the cross tube shows the slight gap at each end, owing to its location slightly rearward than intended. This is easily overcome using a MIG welder, though a longer section would be required if it were to be TIG-welded in place.

While the side 'rails are supplied with welded joints where they're bent, this joint (arrowed) is not welded as it would make fitting the cross tube difficult or impossible. This has to be welded by the installer.

With measurements taken once again, I tack welded the assembly into place, taking note of the instructions to not weld the top surface of the cross tube to the main 'rails. This is because the side braces sit on top of the cross tube and will not fit otherwise. A snug fit, I used a mallet to tap the righthand brace into place.

Here are the braces in place as per Dagel's instructions. Normally they would now be welded, along with the front and rear of the side 'rails to the main chassis 'rails, and the installation would be complete.

However, as my chassis is Z'd, the center of the rearend pinion sits just above the top of the chassis 'rails, meaning the output shaft of the transmission will be at the same height. This put it exactly where the center spacer plate and the middle of the cross tube were intended to be. Normally the rear of the trans would mount below these. With the chassis (and jig!) turned upside-down, I removed the center of the cross tube, placed it at the rear of the central gap, and clamped it and the spacer plate to a length of angle placed across the underside of the side 'rails. With a little trimming of the curved section of the plate, this will allow me to remove my trans from under the car should the need arise. A little forward planning goes a long way if you intend to keep a car for any length of time!