I under stand all the rules for the 130mph club, save for one, and this one is perplexing me.
"• On unibody cars such as Corvair, VW, Porsche, Etc. the fuel lines must be higher than the lowest part of the pan or the unibody structure. They must also be installed inside of a heavy metal tube or above a skid plate. The metal tube or skid plate must be positively attached (no sheet metal screws will be allowed). This is to protect the fuel system from damage if a wheel/tire failure should occur."
I have a Unit body car, although it has a front and rear subframe. To be specific it's a chrysler unit body. Does this mean the entire fuel system must be inside a skid plate or heavy metal tube, running all the way from the fuel tank to the point where the fuel line enters the front subframe? The fuel line closely follows the rear sub frame (as in the OEM application). Getting tubing or skid plates over the fuel line where it follows the rear axle hump is going to be pretty difficult. The fuel line is constructed of zinc plated 3/8ths steel tubing all the way from the fuel tank to the front sub frame, where there are 3" long pieces of rubber hose to make the connection to the fuel tank pickup, and the piece of metal line that runs through the front subframe.
The fuel line routing has it well above the lowest portion of the rocker panels, closely hugging the floor boards. I felt the OEM push in clips were a bit cheese ball so I instead used bolt in retainers with rubber isolation.
If someone could also clarify what constitutes a "skid plate". Can I just form some 18 gauge sheet metal into a box with a flange on either side so I can drill holes and bolt it through the floor board? Say a 3" wide by 1" tall box with a 1/2" wide flange for retention on either side?
I see the rule also says it's to prevent a fuel line failure in the event of a tire failure. Good call, and, the stock fuel line routing actually took it inside of the passenger side rear wheel well. I've changed that routing so that it stays in board of the tires along the rear sub frame. It removed several tight bends and will keep the fuel line safely away from the rear tire. The only thing I can see causing an issue is that if a shock came apart during the run it could possibly hit the fuel line if it swung around very energetically while tearing free from the car. But it would more likely poke a big hole in the fuel tank first.
I noticed in rules for SCTA classes the heavy metal tubing is only required in the plane of the flywheel/torque converter.