Cobra's Custom Shock Project

[Cronenberged]

Thanks for sharing Cobra. I've enjoyed your knowledge on suspensions in the threads. It's always cool seeing the ingenuity of others and what people are still doing to these cars.

[cobra]

Cobra this is pretty inspiring stuff!! Freaking gnarly as hell.

Interesting your choice of shocks were Fox. I see above you said:



Did you valve the shocks each time based on the spring rates you were swapping out? My assumption is yes... but curious if this is a step you took each time or if the valving was wide enough to care for all spring rates you experimented with.

One of the biggest light bulb moments for me in my car tuning (or de-tuning, lol) history has been:

1. Set the car's ride height, measure the hub to a fixed point so I could reference it later (the typical hub to fender on these cars)
2. Jack the car up, remove the spring, reconnect the shock/strut.
3. Raise the control arm to static ride height
4. Observe how little the suspension can actually move before you bottom out

Your diagrams save quite a bit of time in this regard!

For minor spring changes, the dampers don't need to be re-tuned and I can compensate with the adjusters. But the adjusters are non-linear so it's not perfect. Once I settled on the springs I went back and got the valving closer to the middle of the range.

The steps you listed are exactly what I did too. It's nice that the motion ratios are close to 1, so what we see on the shock is very close to actual wheel travel.

[Bry5on]

Hell yeah! I don't currently ride mountain but want to get back into it soon.

I had forgotten it was you who raised up their Dinan springs. That's definitely a good idea.

The Konis have almost no high speed compression damping. The fronts blow off around 4 in/s at 125lbs, and are only making 150lbs at 20 in/s. The rears are even less, blowing off at 50lbs and still only making 100lbs at 20in/s. Of course, these are my Konis with 30k miles on them, but still. I bet a fresh set isn't far off. What you're probably feeling is harshness due to lack of control and then bottoming.

Looks like you were on the money. Today I swapped in Turner camber plates, set to the same camber/caster positions, which netted me 10mm extra travel as measured and I additionally trimmed the top 7mm from new bump stops. This is on top of the 1/2” spaced up Dinan springs. Definitely smoother now, and I do get that slightly uncontrolled feeling from the konis. Well, that and some unwanted NVH from the urethane bushings in the camber plates.

Now you’ve got me considering different dampers.. thanks again for doing the detailed work here.

edit: update for future readers, I wouldn’t recommend trimming the bump stops. Hitting bumps mid-corner is a bit unsettling with the shorter and more abrupt bump stop.