I've wondered for years what was going on under my car in a launch. A fellow racer was kind enough to lend me his GoPro3 to get these shots. These are played back at 1/8th speed.

http://www.youtube.com/watch?v=piGLtGXEa8Q (no sound)

It's interesting to see how much the diff mount moves, and you can see it bouncing around a bit as the car builds speed.

 

Here's a video I made a few weeks ago, it for sure moves around a lot

https://vimeo.com/69433892

 

Great videos guys. I'm surprised how much the center bolt on the diff mount moves around. I wonder if diff mount collars would do some harm since these seem to absorb the shock. Any ideas?

 

^^^ was thinking the same thing. The OEM mounts are rubber and fluid, putting solid mounts there would transmit the rotational shock the axles to the diff itself (pinion gear specifically). The center bolt moves just up and down from Josh's video, suggesting that it's the axle stub shock that is creating the movement (and not vibration or G-forces from the physical chassis moving when driving).

 

Still moves with collars in

http://www.youtube.com/watch?v=oQsnhd7u53s

 

Yes, but moves less = shocks more...

Kind of like when people blow diffs when they remove CDVs or go for more aggressive clutches.

 

Great footage!

 

The first shot where you can see the front diff mount area and drive shaft is amazing. Everything twisting and bending in every direction... I now feel bad launching on slicks. Ill post up how much my rear diff mounts move when i launch, its incredible

 

Agreed. I don't want anything but OEM on my STR car.