US Car Tool torque box and subframe con. install

Some last thoughts. lessons learned: the gas line (right side) and the brake line (left side) go through the subframe connector, so get those in place first, some minor massaging of the lines is desirable. The brake line was covered in an abrasion spiral and we covered the gas line through the connector with oversized gas hose to protect from abrasion. I did this after the connectors were in place the first time - never again. I used stainless steel lines because replacing them would be a bear (gas line more than brake line).

I stripped the floor where the welding was to happen with a wire cup on a grinder, and then painted the floor and the inside of the connector with weld through primer.

There is a bunch of massaging to get the lines to fit cleanly and the connector to fit flush to the floor. The CNC cut connectors do an amazingly good job for a start fitting to the very irregular floor, but add the imprecision of factory panel placement and 50 years of flex, bumps, and what ever got run over that hit the floor pan, you can't expect them to get it 100% correct for your car. This was particularly true of the race car which obviously lost a drive shaft somewhere along the line. It is well worth the time to do careful fitment before the welding starts.

We did this on a lift and took great pains to get the car perfectly level, especially flat from side to side in both the front and the back. I took the extra precaution of using lift floor jacks to support the rear frame rails back toward the bumper and to make them also perfectly flat - this took the weight off the body that would make the car want to 'arch' on the lift. Obviously there was no engine or transmission in (though we did one car with them in place). If they were in place I would have used more jack stands in front for the same reason. ONCE THESE STIFFENERS ARE IN PLACE I CAN'T EVEN IMAGINE A BODY SHOP TRYING TO STRAIGHTEN THE CAR AFTER THE FACT, so we had the car measured 6 ways to Sunday to be sure it was straight before we started and took these pains to be sure it was straight when we welded it up.

I shouldn't have to say this but there can be nothing on the floor of the car when this is done and the inside floor has to be cleaned and repainted after you are done.

Several years ago I went to Carlisle when US Car Tool was up and coming. As always, I made the investment in time to go to Herb McCandless' workshop presentation. Every year I learn something important. That year he had US Car Tool drag their rotisserie display of an A-body up to the tent and went through what they were offering. He said that he would never build another unibody street car from scratch without starting with a frame stiffening kit like this in the beginning. He talked about driving 50 - 70 year old cars around and how this would help reverse the ravages of time. After using the product, I am sold too.