Chassis stiffness

[thstone]

As good as the Boxster chassis is, it is no where close to the stiffness of the Cayman. It is amazing how much strength and stiffness that the roof structure adds.

Take a look at the Boxster chassis shown below - the middle of the car is basically the floor pan - that's it! In some ways, its amazing that the car doesn't simply fold in the middle. As such, there is only so much engineers can do to make the floor pan (a mostly flat panel) stiff.

The Cayman adds the roof which creates a very nice box-like structure to greatly improve chassis strength and stiffness.

A Boxster Spec race car achieves the same by using high strength steel tubes to build a box-like "cage" in the middle section of the car. This cage not only protects the driver in a crash, but adds substantial stiffness to the chassis.

[bwillia080261]

Originally Posted by thstone

As good as the Boxster chassis is, it is no where close to the stiffness of the Cayman. It is amazing how much strength and stiffness that the roof structure adds.

Take a look at the Boxster chassis shown below - the middle of the car is basically the floor pan - that's it! In some ways, its amazing that the car doesn't simply fold in the middle. As such, there is only so much engineers can do to make the floor pan (a mostly flat panel) stiff.

The Cayman adds the roof which creates a very nice box-like structure to greatly improve chassis strength and stiffness.

A Boxster Spec race car achieves the same by using high strength steel tubes to build a box-like "cage" in the middle section of the car. This cage not only protects the driver in a crash, but adds substantial stiffness to the chassis.

Thanks for the awesome graphic! Love it.

[woodsman]

While it's true that there's much that can be more easily improved, stiffness IS the foundation with which all else rests. Can 'we' feel it as we enter or exit a corner or flow over a dip or bump? I think so. I test drove a 911 a while back and was surprised at the noticeable improvement- I went over some train tracks at 40 km and swear I could Feel the roof rails! Ever since I've been wondering how to improve the otherwise spectacular Boxster chassis. Those excellent pics don't show 2 major structures along either side of the floor. These are used when jacking the car up and/or for jack stands. Perhaps they could be fortified. Also I think adding an additional bar ( with triangulation) in the lower door openings perhaps 6-8" above the sill would be of the most benefit. Entering and exiting wouldn't suffer much- it's just the install--weld, bolt or bond?

[Topless]

Originally Posted by woodsman

While it's true that there's much that can be more easily improved, stiffness IS the foundation with which all else rests. Can 'we' feel it as we enter or exit a corner or flow over a dip or bump? I think so. I test drove a 911 a while back and was surprised at the noticeable improvement- I went over some train tracks at 40 km and swear I could Feel the roof rails! Ever since I've been wondering how to improve the otherwise spectacular Boxster chassis. Those excellent pics don't show 2 major structures along either side of the floor. These are used when jacking the car up and/or for jack stands. Perhaps they could be fortified. Also I think adding an additional bar ( with triangulation) in the lower door openings perhaps 6-8" above the sill would be of the most benefit. Entering and exiting wouldn't suffer much- it's just the install--weld, bolt or bond?

A bolt-in cage might be the most cost-effective way to improve Boxster chassis stiffness. It also offers a lot more driver protection for motorsport. I favor a custom welded cage for safety but they are also a lot more $$$.