I have a 2dr X 6 speed with a teraflex 2.5"BB and the teraflex shocks.
1. If i swap out springs with a 4dr rubi will it be too tall for my shocks?
2. will it start causing driveshaft problems, it seems to be around that height that it starts to be a problem?
3. how much lift can i expect with this setup, i have heard of others gaining 1"-1 3/4"?
4. Will this affect my rake at all, mine sets very level curently and i really dont want to change it too much?


Also if anyone is currently running this setup i would be interested to hear comments on ride quility, height, etc. thanks alot

 

is this a horrible idea? no one running it?

 

No lift difference from X springs to Rubi so all concerns are invalid if done...I believe it's alittle bit "stiffer" that's all.

 

that is not what this thread is saying: https://www.jk-forum.com/forums/modified-jk-tech-2/small-lift-66654/

that guy is claiming an extra inch plus of lift but it all depends on getting the correct springs. that might not be the case since mine came with factory hard top so i might already have the HD springs but with all the different spring combos there has to be some difference in length i would assume.

 

I read the thread, found it going all over the place. :(

I remember reading a post of CTIMRUN or something similar and he recently wrote a great post regarding his upgrade to the EVO stuff. Therein he recounted his history of suspension systems he had tried and one of the things that stuck in my mind was the mention of a harsher system using BB type systems which made sense to me since all they do is keep the spring compressed (basically preloading the spring)

No one in that post you mentioned had any idea of the length of springs and some of it was pure conjecture, interesting but when I cough up my money I want a good deal more than heresay. The supposedly longer springs on an unlimited would seem to make logical sense, might give more travel, higher lift without preloading and possibly a slightly stiffer ride, but the ride probably isn't enough to make enough of a difference that you would even remember it on the second day.

Myself, I would welcome less of a dip when I hit the brakes and since I'm getting ready to add on some sliders with strong side protection and a rear bumper with tire support I want to get better springs than what I have stock and possibly about one inch over stock.

The anti-dive might require a front end mod, like lower control arms?

 

I keep seeing this from mentioned from time to time and it doesn't make sense to me. The only way you would be compressing the springs to cause them to ride stiffer would be if you're shocks are bottomed out or you added more weight. The jeeps weight is just setting on top of the springs. and changing the location of that point won't change the pre-load or weight on the springs.

If I'm wronge, correct me, but I would like to see some data on it

 

I sold my unlimited rubicon springs to a guy with a 2 door, he got an inch-inch half out of them. Wiht a 2.5 inch lift you are going to see 3.5 inche maybe 4 inches and with your 2 door you will have driveshaft vibes and/or axle recentering issues. Your shocks will be fine because they limit flex, on normal road conditions it will ride fine. Without control arms its going to wander like a snake.

 

While I cannot provide empirical data I can say this with a straight face.

If you did not add any weight to your Jeep, like sliders, bumpers, winch, large tires and wheels, then yes you'd be correct. However, if you add the things above you have just compressed your springs, hence your jeep sits lower, raising it with BB's keeps the springs at their compressed height plus when you add the spacers you simply lose some articulation and when the springs rebound they "bottom out" sooner due to the preload.

Now the post not too far ahead of this did mention that although the Unlimited Rubi had no difference in height that his two door did not sag as much so the newer springs were most likely a higher load bearing spring (thicker) so he regained his original height and lost no articulation.

Also with just a bit of common sense, you know that a BB is not compressable, allows no movement In any circumstance and is only economical when going for a quick lift. Longer springs can give you a better ride and better articulation, and height. while shorter HD springs give you the same articulation you had to begin with but a harsher ride just to maintain the original height.

Now all we need is an honest shooter, a true spring guru, to figure all this stuff our for us and give us the options. With the advent of the unlimited they just dbled the work needed by those guru's.

 

CIJeep,

Thats the same way I see it also.

By adding the additional items will cause the springs to compress and comprimise the ride, but it will not ride any differently with or without a BB on the road. Now offroad, it is a different story. You will bind the coils easier if you're bump stops are not long enough and that will limit travel compared to longer coils. Now, if you have added alot of additional weight and run stock springs, you should really use stiffer springs so they are not already compressed while just doing regular driving.

I just see posts that people say that just by adding a BB you make a jeep ride rougher and that just isn't the case as far as I can tell. I base this off of about 15 years of setting up Mid-America stock cars. Granted, the suspensions are set up for completely different applications, but the physics are the same.

At least there are 2 of us that are thinking the same thing

P.S. Sorry if I hijacked you're thread OP

 

Being i have run this type of setup for a year, I have only had problems with the right rear shock due to trying to extend it too far BUT as long as you have installed the bump stops it will be fine.

If you do not have a bunch of weight to put in back it will ride stiff.

4Dr springs gave me an inch before adding all my stuff.