Still thinking alert, take cover immediately

J/K there’s no imminent danger. I was thinking of ways to improve the front of the Sprint-T. Also still thinking about the drivetrain with a possible manual transmission.

Starting with the front suspension and related things I decided it might work better if the panhard rod (AKA track bar) was straight. That requires redesigning to the front part of the frame so there is nothing that the panhard rod has to go around to get from the driver’s side of the frame to the passenger side of the front axle. I did this by moving the front diaphragm that carries the loads from the coilovers to the rest of the frame from in front of the axle to behind the axle. This requires moving the steering behind the axle as well as the steering box back to the kit location. This also means the radiator has to be moved back and up to clear the steering shaft from the steering box to the steering wheel. This is how designing a car goes, you can’t just change one thing, it cascades across most of the car. And I forgot to mention the complete redesign of the bumper support structure because the top and bottom frame rails stop at the front axle.

The other thing I was doing was trying to find a lightweight transmission with overdrive, and basically what I found was the Super T-10 couldn’t be made to have an OD without basically redesigning the transmission because the cluster was a solid hunk of steel. Now if it had followed the path of the sister/progeny transmission that used to be called the Nash 4+1 which uses a cluster with replaceable gears, then I could just have a replacement 3rd gearset machined and installed instead of a full replacement cluster. Anywho, the mentioned 4+1 is now the Super Street Five Speed with much higher torque capacity compared with the Super T-10, and extra weight from the structure to resist loads from the increased input.

The 5 speed handles 600 ft-lbs, compared to the 300 to 375 rating for the T-10, and also has a much lower 1st gear (actually several options that are as low or lower than the lowest 1st gear on the T-10). The price for gearing this low and higher torque handling is weight. The 5 speed comes in at 105 pounds compared with 70 for the T-10. Still lighter than any of the self-shifting transmissions with overdrive, by 60-80 pounds, plus it takes up less room inside the car, especially since on the Sprint-T the inside of the floor is also the top of the bellypan and nothing hangs lower than the bellypan, that’s another design paradigm for the Sprint-T.

The top of the bellypan is attached to the bottom of the bottom frame rail, and if there were no bellypan the bottom of the bottom frame rail would be the lowest part of the car except the wheels, because that lets the car be as low as possible without dragging the road if a tire goes flat. Theoretically all 4 tires could go down and the only thing touching the road would be the tires. This requires the road to be pool table flat, but even on normal pavement I can still get both tires on an axle going flat without anything touching anything except tires. I picked this one up from off-road trucks that need to be able to keep going with flat tires.

Anyway, going from a bent panhard rod to a straight one allows a smaller size rod and also allows changing from steel to aluminum, and the combination allows for the drastic reduction in weight of about 2/3, and as half of the panhard rod is unsprung a reduction in unsprung weight as well. This results in a slight increase in grip on bumpy roads and courses as less unsprung weight improves the ability of the tires to follow bumps without leaving the road. This is why I try to reduce unsprung weight every chance I get.

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