Coilove spring rates

[SuperEx91]

now before anyone asks, i searched for info on this and found a lot. only there was a wide range of answers. i wanted to use coilovers on the front of my ex because of the limited room with my front axle and other reasons of course.
I am trying to research what spring rate and shock travel i should use.

i have the stock 4.0 but would like to eventually swap to a 5.0. so a little heavier spring than normal might be a good idea i figured. i want to go with a dual rate setup. i thought 12" travel sounded nice but am unsure of how realistic this is for my setup.

like i said, i have the stock 4.0, dana 44's, 36's, planning on big bumper, sliders and exo-cage too. i know this is all a factor. also i will be using this for trails, and mud. no rocks.

my general consensus was somewhere in the range of 750-800# springs. but i dont know if this is single spring or dual.

i am pretty clueless as to where to start. any help or advice woud be greatly appreciated.

thanks-tom

 

[white96x]

well if you go with a 12" travel shock you will need a spring length totalling 24" which could be two 12" springs, a 14" spring and a 10" spring, etc., basically the total length of your springs should be double the amount of travel the shock will yield..if you go dual rate which is basically the only route you can go to get the spring rate that you need which would still be tough since you will probably need about 700-750lbs..i personally would do something like a 1000lb 12" main and 600-800lb 12" tender...i'm sure some will say thats overkill but especially if you're going to add a bumper you would rather be on the safe side.

 

[Exploderpilot]

all i know is with a solid axle and tires that big, you want quad wrapped limit straps!

 

[SuperEx91]

i personally would do something like a 1000lb 12" main and 600-800lb 12" tender...

now what would the different length springs change? even with the same spring weights?

 

[white96x]

it would change the overall spring rate...because the bigger the length, the less weight it will be able to hold..for example the heaviest 14" you will find is like 650 lbs so then you would have to use a 10" tender, the heaviest i can find is 800 lbs...so you can see what the difference in spring rate would be..and if you go like 16" and 8" forget about it, the heaviest 16" spring is only 500 lbs

 

[SuperEx91]

i have searched for many coilovers and think i found what i want but i have not found a vendor that offers a 1000# 12" spring or anything near it. Th e highest ive been able to find is a 500# 12" and their longest spring at 18" only goes up to 800#.
Is the 1000# main and 700# tender too much? i am not sure. please offer any suggestions.
thx-tom

 

[redranger4.0]

www.F-O-A.com They make a good cheap coilover. They are new to the industry but they already have a good reputation as alot of guys are starting to use them.

DB_1 has a combined spring rate of 111lbs/in with a 200tender/250main coil setup making his secondary 250lbs/in (14"x2.5" King's)

Michael has a combined spring rate of 145lbs/in with a 250tender/350main coil setup making his secondary rate 350lbs/in (14"x2.0" Kings)

Rick has a different Coilover placement making his spring rates at the coilover much higher then DB or michael, so I didnt include his here.

Equation: Rate 1=A Rate 2= B

(AxB)/(A+B)= final rate

http://www.pirate4x4.com/forum/showpost.php?p=4498183&postcount=2

Those rates you are using are rediculous.

(1000x800)/(1000+800)= 445lbs/in

That means for every 445 lbs on the coilover it will compress an inch. thats a crazy spring rate for the weight of an ex. The bolded section above is about a 91-94 Ex with a 3 link front and a D44.

 

[IZwack]

Wow redranger4.0 -- great info

 

[SuperEx91]

I thought they sounded a little off which is why i asked. i was only going off of info i read on here. That will solve my problem. Thanks for the help

 

[redranger4.0]

I thought they sounded a little off which is why i asked. i was only going off of info i read on here. That will solve my problem. Thanks for the help

No problem, I would just hate to see you driven down the road with a 445 rate that thing would ride like a brick.