borisshnitkin

i just got the eibach prokit installed today. i love the stance except for the rear. it looks kind of low for me. maybe im seeing things? ill post pictures tomorrow and i would like to know what i can do to raise the rear just a bit. can i just use some spring isolators? and where can i get them. i would really appreciate it if someone can help me with this problem.

01 Red WS6

iTrader: (4)

If you go the autoparts store they sell rubber as well as metal spring bushings. They fit between the coils. IT should lift the rear a bit

josh99ta

iTrader: (1)

Maybe I got lucky. My car dropped more than the advertised amount, but my rear is around 3/4" higher than my front, so my car has a nice raked look to it. I'm raising the car with some BMR springs and I worry that I will lose my very nice raked look the Pro Kit gave me. I might be investing in some of those spring spacers and/or some heater hose.

WJ SOM SS

iTrader: (11)

Air Lift bags inside the coil springs. They have been around a zillion years and let you adjust your rear ride height and pre-load your rear suspension for drag race applications... WJ

jimmyblue

iTrader: (11)

Air shocks work. I put them on mine for exactly
this reason.

pimpmaro

You can use spring spacers too. Jeg's has them.

JasonWW

iTrader: (2)

The Eibach rear springs have a bad reputation for being too low and soft in the back. By far the easiest thing to do is add some simple spacers.

http://gmocart2.gmotion.com/store/me...ing_suspension
They run about $5 for a set of 4, can be found at your local auto parts store and are very easy to install or remove. Just lift the rear of the car to unload the spring and put one in the middle area of each spring making sure it isn't going to touch the body. Then lower the car. The weight will keep it in place. One metal spacer will lift it about 1/4" and increase the spring rate just a little. Both are good things. If you need to go higher, install another spacer on the same coil but 180* apart from one another.

If you ever decide you don't like it, just take them out and you will be 5 bucks poorer, so no big deal.

I've been using them for over a year with no problems at all.

buckwild

would these rubber spacers have any effect on the handling of the car?

FrozenMonkey

Jason, you've given me a cheap possible solution to my rear rubbing issue...If you werent a guy I'd give you a hug.

JasonWW

iTrader: (2)

Indirectly, yes. But it is a good thing.
Depending on the spring and where they are placed, they will increase the springs compressed height (increasing ride height) and/or increase the spring rate.

A slightly taller ride height can help prevent the tires from rubbing as well as allow for more suspension travel which means you will be off of the bumpstops more and that means a smoother ride.

So that sounds good and all, but you can have too much of a good thing. Too much ride height might hurt the looks and too much rate might hurt the ride quality.

It all depends on a case by case basis. If you tell me what spring you are using and how much lift you want, I can tell you the new spring rate. It's basic math, but there's lots of variables.

The only difference between the rubber and the metal spacers is that the rubber ones compress some under load. Generally they have about half the increase in ride height and rate as a metal spacer. Say for instance, you like having 1 metal spacer in each rear spring, but the passengers side needs to come up about 1/8" just make both sides perfectly level. If you add a metal spacer it will lift it about 1/4" which is too much. The rubber spacer however will give you that smaller increment. So one rubber spacer and one metal spacer on the right side and one metal spacer on the left would give you that perfectly level look you want.

That's just an example, but I hope it all makes sense.

Jason

buckwild

so in effect i could also fix the uneven/slight lean toward passanger side, that many camaros have by adding a spacer in that spring. also how much (on average) could you adjust with spacers before having a negative effect on handling. to help with an example i have eibach pro kit on a 99 camaro and would like to raise the rear around a half inch, and also the passanger side slightly to fix the uneven stance.
-shawn

JasonWW

iTrader: (2)

Yeah, you could trim the taller spring ever so slightly or raise the shorter spring by using a small spacer of some kind. Sometimes you can simply swap rear springs or rotate one of the rear springs to make things even.

That's not really the question. The question you should be asking is "how much (on average) could you adjust with taller or stiffer springs before having a negative effect on handling?"
Because that is essentially what you are asking. As far as ride height, you can go really high without many side effects, but the question I think you are most concerned with is the spring rate.

Increasing the rate has both positive and negative attributes. As you go up in rate, you can prevent the suspension from bottoming or using the bumpstops and that is good. You can prevent the tires from rubbing the fenders if they do that. It can reduce the speed in which the nose dives under braking as well as reduce the nose rise under acceleration. It can make the rear of the car respond quicker to input and feel more solid in the rear.

The down side to increasing the rear spring rates is that the ride quality will suffer the higher you go. Eventually you will find the ride too stiff to be comfortable. It will also reduce the grip in the rear under cornering loads. This will tend to make the cars balance move towards oversteer. Just like puting a stiffer sway bar on the rear, the stiffer rear springs will generally make the rear slide out more easily in the corners.

Much has been written on spring rates and car balance, but I just touched on the main issues. Just to give as an example, I found that with my Koni SA rear shocks (set at full soft), custom bumpstops and a 26 1/4" ride height that 170lb is just about the most I was comfortable with. I tried 190lb, but I felt it was borderline too rough riding. So I backed it down to 170lb. Combined with the stock 19mm rear bar and the rest of my suspension setup, the cars balance is very nice. It tends to be balanced evenly and can be coaxed into oversteer with the throttle. It's comfortable on a daily basis and I can take dips at speed without the 315's rubbing or hitting the stops too hard.

I've seen pics of the Eibach Prokit. On those rear springs you have 2 different places you can put a spacer-s. They are a progressive rate spring. In case people don't know how those work, I will explain. Simply put, the spring is made with 2 different coil spacings. Some of the coils are spaced closely and the rest are spaced further apart. The exact spacing and how many of each is up the the manufacturer and varies. So what happens is that the load of the vehicle will compress the entire spring and at ride height, the closer spaced coils will almost be touching each other. At this point the entire weight on the spring is divided among all the coils whichs gives it the lower of the spring rates. (Eibach lists the rear spring as having a rate of 80/137lb) So you are riding on the 80lb per inch rate until the suspension compresses. As it compresses the closely spaced coils will touch one another and you get what is known as coil bind. So that part of the spring no longer contributes to the load bearing duties. The more widely spaced coils are not touching/binding and now take care of all the load bearing issues. Since there are fewer coils being used the new spring rate is 137lb/inch. and stays at that rate until you are on the bumpstops or the suspension starts to un-compress.

Now as the suspension starts to extend, the coils will eventually not be binding and you will be back using all of them in which you will be back to the 80lb/inch rate again. This sounds good and all in theory. You have a soft ride and then it gets stiffer as the suspension compresses. Nice huh? The down side is that it plays havoc with getting the shock valving to match up. Shocks are usually optimized for a specific spring rate and having 2 different rates means adjusting the shock to match one rate, but not the other or to maybe have it in the middle as a compromise. Neither is a very good solution. That is why most racers and suspension folks will tell you that linear rate springs are the better choice. The shocks can be matched up and you will have them properly under control and the handling and ride will be very good as well.

Anyway, I wanted to put both sides of the argument on progressive rate springs out there. To get back to buckwild and his Prokit rears, you can place a spacer into the closly spaced coils (if you can) or in the widely spaced coils. The former will increase ride height with minimal increase in spring rate. So if you don't want more spring rate, try one or two spacers in the closely spaced coils. You might have to pop the springs out and wedge the spacers in with force. Try one in each side at first and see what effect it has on ride height. I've never experimented with those specific springs, so just go for it and see if you like the results. It you need more height, add another spacer 180* apart from the first one. Make sure they won't rub any part of the body once they are in there and your going down the road. Once you get it about where you want it and you think one side is just a little higher than the other, you can add a rubber spacer to make the lower side go up just a little more or you can replace a metal spacer on the higher side with a rubber one to make it go down just a little more.

JasonWW

iTrader: (2)

Buckwild asked this on another thread, so I wanted to put the info here as well, seeing as they are related.

Ahhh, in this question you ask how spacers can effect the RATE. Yes they can. Just like cutting the coils can effect the spring rate.

One one hand, I like being one of the few to have this info, but I guess I'll share cause I like helping you guys so much.

Ok, lets use the stock rear spring as an example. It is a linear rate 115lb per inch spring with about 8 coils total (I'm rounding off). As a side note, there are 2 factory springs with the same height and rate, just a different number of coils. Wierd, huh?

Anyway, first I should mention how spring rates are measured. The 115lb rate means that it takes 115lbs to compress the spring 1 inch, 230lbs total to compress it a total of 2 inches etc... Make sense? This is a linear rate in that it doesn't change. Progressive rate springs will change rate due to the way they are wound. I mentioned that above.

The coils on each end are compressed and are mainly used to hold the springs in place. They are considered the "dead" coils as they do not contribute to the load bearing duties. Only the 6 "active" coils are actually doing the work. So we take the 115 and divide by 6. We now see that each coil is responsible for 19.1666lbs (or 20 if we use round numbers).

So for instance, if we cut off one complete coil, the springs new rate will be 20lbs higher or 135lbs per inch.

Or, if we instead add 2 metal spacers, 180* apart in the middle of the spring we are essentially making one complete coil "dead". The effect on spring rate is the same 135lbs per inch.

The only difference in these 2 techniques is that one way lowers and one way raises the ride height.

Doing both will make the rate 155lbs per inch and keep the ride height about the same.

Cutting half a coil or using one metal spacer will have half the effect or increase the rate to 125lbs per inch.

It's pretty simple. Keep in mind that rubber spacers will compress and tend to have half the effect of the metal spacers (assuming they are both the same size). There are different rubber densities as well among the different companies that make them.

Things get a little more complicated when dealing with progressive rate springs and then there are differences in where spacers are placed in the spring and other things that are hard to explain. I won't go into detail on that, but hopefully this will be helpfull to you guys.

Let me know if you have any more questions.
Jason

buckwild

thanks for all of the great info, very helpful
-shawn

mitchntx

iTrader: (14)

If you shim it on the top or bottom, the rate remains unaffected but the ride height increases (longer effective spring).

JasonWW

iTrader: (2)

If you mean above or below the dead coils, then yes, the spring is not effected. Only the ride height is increased.
If you mean putting a spacer into the dead coil, then the rate does change, but only fractionally, IE. not enough to notice in the example I used.

mitchntx

iTrader: (14)

http://www.pitstopusa.com/detail.aspx?ID=23987

http://www.pitstopusa.com/detail.aspx?ID=23986

DietCoke

iTrader: (18)

Get LCA relocation brackets. Not only will they benefit your car's handling, they will raise it up in the back.

ssPetess

iTrader: (8)

What??? They will not do either...

DietCoke

iTrader: (18)

Yes, they will. LCA brackets do indeed slightly raise your rear suspension height due to the increased upward leverage levied upon the chassis and help eliminate wheelhop on a lowered car. Next time your around anyone who's getting it done, your welcome to measure and see for yourself.