Coil-over question

[JPTHING]

So I have my MJ suspended, now but I am assuming that the spring rate of the heavier springs is a little too much. When I place the weight of the Jeep on the springs, it only compresses about 1 inch. Which sets the top of my Jeep at about 8'6" which I think is a little too tall, and if I end up going with the 44" tires I want, it will be about 9' to the top. What spring rate is everyone else running, with a heavier engine. Mine is 450, and 300 I am thinking that I should go to about 250 and 150. Let me know whether this is too low/high, or what will work better.

 

[Roccrawler]

your asking a question that just cant be answered correctly. Its like saying my truck is making a rattling noise what do you think it is.

My first answer is yes 250 X 150 is closer to start. But you will find a lot of trial and error to get it just right.

How long of coils are you using also. you may need a helper spring also. alot of rigs are using 3 springs to get proper ride height.

 

[Brian H]

your asking a question that just cant be answered correctly. Its like saying my truck is making a rattling noise what do you think it is.
My first answer is yes 250 X 150 is closer to start. But you will find a lot of trial and error to get it just right.

How long of coils are you using also. you may need a helper spring also. alot of rigs are using 3 springs to get proper ride height.

Well duh.....its cause its a dodge.

 

[bobbed_84_toy]

Which sets the top of my Jeep at about 8'6" which I think is a little too tall, and if I end up going with the 44" tires I want, it will be about 9' to the top.

:eeek: yikes! My yoter is 85" to the top on 44's. I heard that Dave(?) at poly performance is a lot of help when it comes to setting up coilovers. You might wanna try to get in touch with him:awesomework:

 

[megatoy66]

8'6"...........Damn. :eeek:

 

[benw1]

It must be compressing more than an inch unless something is binding. With 300 and 450 springs your primary rate is 180 lbs/in. If its only compressing 1 inch then that means you only have 180 lbs of sprung weight per corner, no way is that possible. 150 over 250 has a primary rate of 94 lbs/in, so it will compress about twice as much as it does now.

 

[JPTHING]

your asking a question that just cant be answered correctly. Its like saying my truck is making a rattling noise what do you think it is.

My first answer is yes 250 X 150 is closer to start. But you will find a lot of trial and error to get it just right.

How long of coils are you using also. you may need a helper spring also. alot of rigs are using 3 springs to get proper ride height.

First off I don't want it to be setup for triple rate this is not a desert truck.

:eeek: yikes! My yoter is 85" to the top on 44's. I heard that Dave(?) at poly performance is a lot of help when it comes to setting up coilovers. You might wanna try to get in touch with him:awesomework:

That is who I bought the springs from, and he said I should start where I am, and go down from there.

It must be compressing more than an inch unless something is binding. With 300 and 450 springs your primary rate is 180 lbs/in. If its only compressing 1 inch then that means you only have 180 lbs of sprung weight per corner, no way is that possible. 150 over 250 has a primary rate of 94 lbs/in, so it will compress about twice as much as it does now.

It is not binding, it moves freely, and it would be great if it compressed twice as much as it does. I just want an average of what everyone is running. I don't want to spend the next six months figuring out what the perfect combo is.

 

[Roccrawler]

First off I don't want it to be setup for triple rate this is not a desert truck.

aah I see your knowledge is showing

triple rate has nothing to do with desert trucks, but I see you have it all figured out. so good luck :looser:

 

[JPTHING]

aah I see your knowledge is showing

triple rate has nothing to do with desert trucks, but I see you have it all figured out. so good luck :looser:

Sorry I am sure I don't have the knowledge that you have about this, but I have never seen a crawler worth a **** that required triple rate springs. Isn't the third short spring specifically for soaking up small bumps. That is what I was told.

 

[Roccrawler]

Sorry I am sure I don't have the knowledge that you have about this, but I have never seen a crawler worth a **** that required triple rate springs. Isn't the third short spring specifically for soaking up small bumps. That is what I was told.

No

 

[pbmcauliffe]

The third smal coil is a zero rate tender, used to keep some downward pressure on the springs when fully extended to keep the springs from bouncing around and coming unseated. Depending on the springs length and the up/down travel you don't always need them.
I run a 150/400 on the front of my Jeepster and 100/400 rear, Jeep CJ5 we just did turned out at 200/250 front, 150/250 rear, recent Toyota was 150/200 in the rear.
Take the secondary spring off and keep the main on the rig, measure the free height within a 1/16" of an inch, set the rig down, shake it a bit and re-measure the length within a 1/16", with the known rate and deflection you can get close to the weight and go from there.

 

[Roccrawler]

The third smal coil is a zero rate tender, used to keep some downward pressure on the springs when fully extended to keep the springs from bouncing around and coming unseated. Depending on the springs length and the up/down travel you don't always need them.
I run a 150/400 on the front of my Jeepster and 100/400 rear, Jeep CJ5 we just did turned out at 200/250 front, 150/250 rear, recent Toyota was 150/200 in the rear.
Take the secondary spring off and keep the main on the rig, measure the free height within a 1/16" of an inch, set the rig down, shake it a bit and re-measure the length within a 1/16", with the known rate and deflection you can get close to the weight and go from there.

almost like you knew what you were talking about :redneck:

 

[Roccrawler]

and your explanation sucked :;

 

[pbmcauliffe]

almost like you knew what you were talking about :redneck:

I stayed at a Holiday Inn Express last night. :haha:

 

[pokey]

and your explanation sucked :;

Quit trying to be such a Jobless

 

[XtrmTJ]

I use 2.5" Sway-a-Way/Race Runners. It took me three (3) trys to get it right. I use 185 lbs over 250 lbs springs with a spring tender spring (third spring). I have a '97 TJ with 38.5's. This is not a DD so alitle body roll is ok with me. I want loads of articulation. :awesomework:
Hope that helped ?

 

[Roccrawler]

ok to answer your question about a third spring..

sometimes you need to run a shorter top spring to get ride height . You just cant put softer springs on to lower your ride.It may soften up your suspension to much. a top tender coil squishes flat just to expand at full droop and not let your coils fall off.

So if you like the spring rate now and want to lower your ride 2" you would need to shorten the top spring 2" plus the collapsed helper spring and extra spacer subtracted overall

 

[pokey]

ok to answer your question about a third spring..

sometimes you need to run a shorter top spring to get ride height . You just cant put softer springs on to lower your ride.It may soften up your suspension to much. a top tender coil squishes flat just to expand at full droop and not let your coils fall off.

So if you like the spring rate now and want to lower your ride 2" you would need to shorten the top spring 2" plus the collapsed helper spring and extra spacer subtracted overall

that wasnt so hard now was it:awesomework:

 

[Roccrawler]

that wasnt so hard now was it:awesomework:

yes, yes it was :flipoff: