Airbag 4 link for drag racing.

[Macktruckdriver]

I'v finally started my short box 2wd 10 second/Street truck build. Down the road I will eventually be doing a back half with a 9" but to get rolling and work my way up I just shortened the frame this past weekend. I had an idea to 4 link it for now and use air bags instead of coil overs so I can remove the springs and tuck a bigger tire under the box. Has anyone ever used air bags and how did that work?

 

[Highwayman]

I would think that would be hard to dial in. Doesn't seem possible to be anywhere near as consistent as a coilover.

 

[CorneliusRox]

I would think that would be hard to dial in. Doesn't seem possible to be anywhere near as consistent as a coilover.

It depends on what kind of airbag. The 'high load' truck/tractor-trailer versions are going to be inconsistent, but the performance car world has come a long ways.

They use very small inlet orifices (so pressure can't escape as fast when under compression), and skirts around the bag on the top to keep the bags from bulging too much.
They're also not just a bag, they're typically a strut/coilover design.
People hit 10's with them in only slightly modified Audi's and they launch hard!

We're also talking IFS/IRS vs solid axles with leafs, so at a minimum you'd want a good four link setup in the rear.

 

[Macktruckdriver]

With air bags I was thinking run then individual so I can adjust air pressure or should I just tie them together and run equal pressure?

 

[CorneliusRox]

With air bags I was thinking run then individual so I can adjust air pressure or should I just tie them together and run equal pressure?

I'd do individual, or get a manifold where you can set pressure specific for every bag with a compressor and PID controller to account for leak.