Pics & Review of My Bilstein PSS10 Lowered Red Turbo by cannga

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Track Oriented JRZ/Moton vs. Street Oriented Bilstein - which is "better"?

This is a repost of a discussion in another thread that I thought was somewhat interesting. 

When one looks at coilovers, there are in general two main classes on market: 

a. Very expensive, all-out design that is geared for extreme conditions (high spring rate, high temperature, extreme ruggedness) of the track such as JRZ/Moton

b. Street oriented design such as Bilstein Damptronic.

You probably already know the obvious answer - neither is better. The primary reason is that JRZ is a very stiff system that is designed for smooth surface of the track, whereas Bilstein is a more compliant system designed for street driving. You pick the coilover depends on what you like to do with the car.

Road surface condition is a critical factor in selecting suspension & spring rates. Stiffer is better for weight transfer reduction, but it's bad when road surface is imperfect - this is one of the many trade-off's involved in suspension tuning, and there is never a best suspension for all conditions. The reason is that as suspension gains stiffness, it actually loses traction when road gets bumpy, with tire and car leaving road surface on road bumps at high speed. And really there is nothing more dangerous and scary   than going airborne from a bump in a curve. Without steering input momentum carries the car straight, while the road is curving, you get the picture.

At the track, with smooth surface, for **very** advanced track driver, and with an experienced tuner, JRZ is indeed "best." On regular road however you are better off, might even be faster, with a more compliant suspension designed for "regular" road. Professional race tuners do de-tune the suspension with softer springs when they see bumpy road surface; this rule applies to pro's and amateurs alike.

Note that when you are tuning a suspension system, you are not just changing the coilvoer, there are other things to add depending on what you are looking for, such as R comp tire, sway bar, drop link, rear toe link, etc. If stiffness and ultra-precision is what you are looking for, even with a moderate system like Bilstein, you could add components to the point that you and your dental fillings have more than you could handle.

Of course, the problem with precise and stiff suspension components is that they *all* will add vibration and harshness as well. Stiffness is fun for short drive and at the track but actually wear on you and become extremely unpleasant for road driving; people have had to remove JRZ because of its stiffness (real example, not rumor). 

It is impossible to "soften" a track system like Moton, first why would you want to do it and defeat the very purpose of its existence, second, even with the lower spring rates they still are very stiff; it has to do with the damper and how the shock is made (less rubber, more metal at interfaces), but that's another discussion altogether. For this reason, for the amateur drivers that most of us are, it's much better to start medium, then go stiffer (Bilstein + components), than to start out very stiff and got stuck with it (JRZ).