The mystery called chassis

[ajg1030]

The Chassis is harder to define in a formula car when you are comparing it to a road car. In all Formula cars the engine and gearbox are stressed members of the chassis. The Monocoque we also call a tub. The carbon tub is the main part of the whole car and can be defined as the chasis.

The rear suspension is mounted to the gearbox in most all formula car designs and to some degree directly to the engine block in F1. Why not add weight to the engine to make it stiffer?? Easy. The goal in F1 is to move as much weight to the front of the tub as possible in recent years.
This puts more pressure on the front tires and allows the car to corner better. The more mechanical grip you have up front means less aero pressure needed. So you have a net gain in speed as a result of less drag.

CFDruss- actually the engine and gearbox are bolted directly to the tub. So whole suspension is dependant on the total torsional rigidity of the tub+engine+gearbox to be effective. The less flex you have from front of the tub to the rear of the gearbox the more effective the suspension will be. It will be more predictable and the engineers will be able to make smaller adjustments to the car to make it handle better.

[red300zx99x]

Every think about the term 'rolling chassis'?

[ajg1030]

Yeah well rolling chassis is a liberal use of the term in formula car racing.
Since the gearbox is mounted to the engine and the engine to the tub. Take the engine out and there is no way to mount the rear suspension to make a rolling chassis. The gearbox and transmition are pretty much what create the rear rolling environment.

So a roller in formula racing means that you dont have a working motor for the most part. If I disconnect my motor from the tub then the whole rear of the car sits on the floor. In those closed wheel cars they can remove the motor since their suspsension in mounted to a more tradditional chassis. The sports prototype guys have the same situation as the formula cars as far as I have seen. They are basically a formula car with bodywork.

[Lukin]

To add my 2 cents in (2 months late) I agree with Red's sentiments.

I consider the chassis to be everything except that which drives the car. Therefore pretty much everything except the engine and drivetrain is the chassis.