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| Due to the Scion’s carbon fiber composite roof, we wanted to make sure that the driver would be adequately protected from intrusion during a violent rollover. For the added protection an X halo of steel was built over the roof opening. Normally a single cross bar would be adequate |
We had to do some different things to the cage to take some of the differences of the Scion TC’s body structure from other cars into consideration. As with most of our cages, we used a large degree of triangulation in its structure. The triangle is the strongest and stiffest geometric shape so by nature by reducing the cage into a series of triangles, we can get the best combination of stiffness, light weight and overall strength.
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| Odyssey supplied the lightweight gel battery and strong bracket. This takes over 40 lbs off of the nose of the car |
The TC has a completely open roof structure to accommodate its attractive huge glass roof. While this is a very cool feature on a street car, we had to build more cage than usual in place here to protect the driver in a roll over much like you would when building a cage for an open top roadster. We built a strong full X cross brace over the open roof to give added protection.
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| The Recaro seat is comfortable, lightweight and FIA approved, eliminating the need for a back brace |
The Scion TC’s sleek aerodynamic body also means that the “A” pillar has a steep rake and the forward part of the cage has an extreme bend as it comes up from the floor and a shallow bend as it reaches the top of the roof. This means that the cage is less resistant to downward crushing in this area. The smoothly arcing roof and far rearward position of the main hoop also means a big unsupported area for the front hoop of the cage.
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| Driver positioning is critical and Dan Gardner is being fitted in position in his car |
To combat this inherent weakness we added an additional vertical bar to shore up the “A” pillar and an additional bar going from the main hoop to the roof area to reduce the big expanse of unsupported roof. These are details that should not be overlooked when building a cage for the TC and other highly aerodynamic cars with raked windshields like perhaps the current Honda Civic.
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| Strong seat mounts are critical. In a crash forces as high as 6 G’s or six times the force of gravity can be generated. With cantilevering of the loads due to the seat height and the length of drivers body, this means forces of several thousand pounds can be generated |
To save weight we gutted the doors window mechanisms and removed the crash intrusion beams. This saved a bunch of weight, about 40 lbs per door. We used an interrupted “X” door bar for the cage itself. The uninterrupted X combines the best attributes of light weight strength and stiffness in a cage door bar. We also added a NASCAR bar to the driver’s side door with a bit of a twist to it. Normally NASCAR bars are strong ridged thickwall door bars that extend all the way to the inner skin of the door. Our NASCAR bars is a single bar with tether bars which is designed to crush and dissipate the force of a severe side impact while the uninterrupted X serves as a nearly impenetrable barrier between the driver and the impacting object.
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| The seat in place |
At this time we also relocated the battery. The stock Scion TC Battery is huge, heavy and hung way out over the nose of the car in the absolutely worse place to mess up handling. We replaced the battery with an Odyssey PC680 drycell battery. This battery at 12 lbs is about 1/3 the weight of the stock battery. Being a drycell makes it much safer as it doesn’t issue flammable hydrogen gas or spew acid. To help get weight off of the nose of the car, we relocated the battery to the inside of the car on the passenger side where the base of the rear seat would be. Believe it or not this change makes a full percentage change in the cars weight distribution, which makes a feelable difference in the cars handling. Odyssey also makes a bulletproof mount for this battery, something we feel is essential for safety. We have seen aftermarket battery boxes and mounts fail in severe racing accidents allowing the battery to fly around inside the car like a sledge hammer. This is very unlikely to happen with this lightweight battery with its strong mount.
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| The X brace is finished off with this dimple die punched gusset which makes it super strong while adding little weight. The tubes in front of the bar are an impact absorbing structure which is designed to collapse under a severe side impact and reduce the G load on the driver. The impact absorber is made of a lighter gauge tubing than the rest of the cage |
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| A side look at the critical door bars and the side impact absorber structure |
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| Another look at the cages triangulation |
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| After all of the cages bars are in place and the seat location is set, the harness bar is placed so the harnesses have a straight shot at the drivers shoulders. This is very important to reduce the chances of spinal compression |
