is 50/50 weight distribution best for prerunning? what kind of shock valving? my fox shocks are valved 40/80 and they work really well trailriding(rocks, waterfalls) but it seems there is too much rebound for prerunning. not sure where to start with the shocks, spring rates are good for my jeeps weight, so tunnig shocks should work for me.....any tips to send me in the right direction are greatly appreciated :)

What's the weight of the truck, and are they 2" 2.5" or 3" shocks?

2 inch shocks. jeep weighs 2090 front 1620 rear...about 1500 sprung weight front and about 1100 sprung weight rear......

no help on this, wrong forum maybe??? im not looking for exact valving, just some tips on weight distribution and if alot of rebound is bad.......

More weight towards the rear is better, and high reb is not always a bad thing.

I'm Running 55/45 front to rear bias More importantly, the pivot point of the weight bias is directly under my ass. Why is this important in the whoops? The vehicle moves the least at the pivot point thus beating the passangers the least. Spring rate is waay different from crawling to pre-running. I'm running 250/250 in the front and 175/250 in the rear with 15/12 valving on 2.5" shocks with 4" hydro bumps. The truck handles as well as a 107" wheelbase with 60's can. Its pretty impressive.
http://rides.webshots.com/photo/2040956500050686511ksIsoG
http://rides.webshots.com/photo/2916779140050686511EzodYb

what is 15/12 valving, is this off a fox chart? is there a formula to find the pivot point?

what is 15/12 valving, is this off a fox chart? is there a formula to find the pivot point?


15/12 is a sway a way measurment, ever mfg uses a totally different chart, beat95 can probably explain how they all compare, but all mean extremly different things.

what is 15/12 valving, is this off a fox chart? is there a formula to find the pivot point?

If I'm not mistaken, Fox's version of a 15/12 would be 90/70. It would be nice if every manufacturer used the same units.

Garrett

You cannot directly compare like that. A .015/.012 on one pioston will not provide the same damping on another piston. I would be suprised (hell amazed) if both versions of the SAW piston had the same loads with those stacks. The pistons are too different.

Good point, that didn't even come to mind. So the only similarities would be the washer thickness, making a standardized valve rating unit kinda useless I guess.

Good point, that didn't even come to mind. So the only similarities would be the washer thickness, making a standardized valve rating unit kinda useless I guess.

Unfortunately Yes. It may assist in getting someone into the ballpark, but even then I doubt it.

Unfortunately Yes. It may assist in getting someone into the ballpark, but even then I doubt it.

What we need is for each piston to be characterized and then paired w/ the chart of shim thicknesses to give approximate damping coefficients. With that you can compare easily between shocks and actually start to compare damping ratios between different setups to help with tuning and initial setups. Has this data been collected and made available for the Fox and Swayaways?

As far as I am aware no damping curves are available from SAW, King, Radflo or Fox. It is my impression that the majority of these companies do not have access to a shock dyno.

That's retarded. They would HAVE to own shock dynos I'd think. Hell, I have access to simple shock dynos. I've always wondered why those numbers aren't readily available. I hope it's not because of lack of effort.

Actually I'm running King shocks the rock crawling valving was 18/22 all it means to me is what shims I put in the stack.The 15/12 allows for stiffer compression and faster re-bound where the 18/22 is for the oppsite. I think the differences in everyone's measure is the reason why desert racers are reluctant to change shocks, its what they are used to. I spoke with a Faber/Tuner at the primm that was complaining about tunning Fox shocks and that it took 15 min with Kings and 3 hrs with the Foxes. I've heard the same story the other way. I must say even set up for speed the my cruiser still crawls well. I have to get lighter springs for the front and lower it for the walls but otherwise it works well.

We jacked it up and took 2 big jack stands and moved them around on the frame rails with the shocks off until it balanced. Yes there is an equation but it would take days to gather the information required to make it work. Jack stands and beer is faster. The balance point was almost there already the addition of the spare tire carrier finished it off. I've also added a larger fuel cell (32 gal up from 22) and plan to slide the motor back 2.5" I'll be going to a shorter tranny(700r4 to th350) and atlas so the mean effect should be small if any in weight distributionto the rear but it will amplify the effect of the larger fuel cell and spare tire carrier hopefuly It will balance closer to 50-50 but keep the pivot point about the same.