Shock set up for jumping

[steve-oh]

Sold my prerunner build to my son, building a tube chassis ranger mega truck now, had some good info passed on from here so figured I'd start here, I'm using some 14 inch 2.5 fox coilovers and a hydro bump, where would be a good place to start for valving in the shocks? Be hitting jumps, lots of 4-8 foot holes at pretty decent speed, won't be for a extended amount of time, maybe 10-15 min runs at a time.

[SteveG]

Kris?

I'm no guru, but hard hits are all about maximum orifice... limit the amount of fluid that can get through the piston. This is quite the subject. We have a couple great shock tuners on the site. Hopefully they'll chime in.

[steve-oh]

That's what I was hoping for.

[hollandermotorsports]

Ok here is my opinion take it for whatever it is worth. Jumping is very hard on chassis so for starters make sure you build a chassis strong enough to take the abuse. Now if you are jumping big jumps then you want a lot of compression and some rebound. With that said shock shafts do not like a lot of compression at full droop. A 2.5" usually have a 7/8" shaft which can and will bend. I would look towards doing a big bypass for the different stages through travel to progressively stiffer. Coil over you will have the same valving through travel therefore it will cause the hydraulic effect at full droop. Your other option is a threaded body air shock which has a huge shaft and the shaft displacement increases pressure internally as it compresses basically increasing compression. just my .02

I maintain Adrian Cenni's barrel roll truck that slaps hard from jumping and it constantly has bent shafts.

[steve-oh]

That would explain why the trucks doing big air are using the nitrogen shocks and no coilovers then.