14 inch coilover question

Brad597 · May 18, 2013

I'm running 14 inch coilovers on my jeep tj,
Front is 200 over 300
Rear is. 150 over 250
My top springs are 12 inch springs, and the bottoms are 16 inch.
My question is, on the rear my top springs are squished flat.
Should I just change out top 150 springs to a 200? Or what?
Any help would be greatly appreciated.

Also, I don't have scales to weight the rig.

al1tonyota · May 18, 2013

There are a lot of factors that go into it but a rough way to get close on weight is measure how much the springs compress with the weight on it. For instance a 150 lb spring that is compressed 3" has around 450 lbs on it. A 300lb spring would only be compressed an inch an a half Are you trying to raise the ride hight? If you are just worried about the spring being compressed and put a stronger spring on it it will change your ride hight .

Brad597 · May 18, 2013

Not really wanting to change ride height.
I was just worried about the rear top springs being totally flattened.
There is no adjustment on them they are so soft.
I have to tighten the coil adjuster (ride height adjustment) all the way down just to get enough height not to be scrubbing anything.
Do you think it would be ok to swap to a heavier rate spring?

SomewhiteGuy · May 18, 2013

You can run a higher rate coil and just run less preload to maintain ride height. The ride will be stiffer. Right now with 150 over 250 you have an 93.75lb initial rate, going to 175/250 is 102lb initial, going to 200/250 is 111lb initial.

Brad597 · May 20, 2013

Does anybody have a coilover setup on a full bodied jeep tj?

BUG-E J · May 20, 2013

Weigh your rig. Call EOR and tell them what you have and whats going on. Send them the shocks and let them tune them. You will be surprised what you can pay somebody to get your coilovers "right" with little to no headache. And when you get shocks dialed in you will be MUCH happier.

Brad597 · May 21, 2013

Thanks

billstoy · May 21, 2013

If you are happy with the ride and flex, the top spring does the light work, the bottom heaver spring takes the tough stuff deep hard bumps. A stiffer spring will change ride and ride height. If you are happy the spring in no big deal.

Brad597 · May 22, 2013

So your saying with my jeep just sitting at static height with the tender spring totally flat is ok?
And the ride is not good, it's real bouncy in the rear.
Every dual rate coilover I have ever seen, I've never seen one sitting still with the top spring flat.

billstoy · May 22, 2013

It will not hurt anything to run a compressed spring,,, if you were happy with the ride! most crawlers have very little up travel and most down travel .that is what you have. If the ride is bouncy that is your compression and rebound settings in your shocks , also to keep the same ride height you would need to change both top and bottom springs, As someone else stated People invest 1000S of dollars to to get the ride they want . Most people set up a buggy to sitting at rest 33 % up and 66% down travel look at the popular buggies! I have changed top and bottom springs 4 times and may still change again! I need lighter rear springs for more droop and weight transfer on my buggy it is light but I run 100s and 150s so I dont have one flat spring like you have! There are many other people on here to chime in. opinions are like ass holes everybody has one. you asked so I gave mine! buy used springs and sell used springs I have some if let me know length ans weight and 2 or 2.5 shocks?

Brad597 · May 23, 2013

Cool, thanks for the info
When I find out what springs I need, if I need any I will holler at ya.
Thanks again

billstoy · May 23, 2013

F.O.A. has a great spring calculator on their web site you need to guess your weight by the amount of spring droop ypu have now.

Brad597 · May 24, 2013

Is there anywhere close to get my jeep weighed correctly?
I live in northeast MS.

TBItoy · May 24, 2013

Re: Re: Re: 14 inch coilover question

Brad597 said:
Is there anywhere close to get my jeep weighed correctly?
I live in northeast MS.

You can calculate the weight from how much the springs. compress.

I'd jack it up, take all pre load off, then run the dual rate stop down to the top of the lower spring (thereby taking the upper spring out of the equation).

Set it down and see how much the lower spring compresses. Then you'll know how much weight you're holding up.

The overall weight of the Jeep isn't that important to spring selection

SomewhiteGuy · May 24, 2013

Tbi is correct you need to do this to determin your sprung corner weight. With that weight you can figure the springs needed to set ride height then you can start working on tuning the valving in the shocks to get the ride you want. On my buggy I got the springs right the first time but revalved 4 times till it was right then changed engines and Had to start again due to adding 125 lbs to the front and changing the F/R weight bias the rear shocks have to be tuned again as well to get the best performance.