Jay J

I'm planning on purchasing the H&R Sport Springs for my 99 A4 1.8TTip but I was wondering which shocks to get: Bilstein or Koni. I've checked the archives and only read good stuff about both of them but is their any major differences between them. Any advice would be greatly appreciated.<p>

HermanH

From what I can remember, the biggest difference is the Bilsteins are a Nitrogen Gas shock, vs Koni's oil shock. Nitrogen as you may know, is an inert gas; under the types of temperature variances from -30 deg. to 115 deg. F., the Nitrogen gas maintains a consistent "viscosity" - not really a good term but the best I could come up with. In contrast, oil will vary in viscosity once it get's beyond it's temperature range; this can lead to inconsistencies in dampening, which is a good reason to have an adjustable.<br>I'm sure Koni does a good job of ensuring the oil it uses has a wide temperature range so I hope this answers your question. BTW, I'm no expert on this; this was just old talk from about 15 years ago with friends of mine. However, Koni and Bilstein have not changed much in that time. Also, I believe both companies carry lifetime warranties.<p>HermanH<br>98.5 Passat 1.8tm

randall

had them on the laser/talon, had to turn down damping in the winter, they were JUST TOO STIFF!!<p>otherwise great shock, had for 6+ years, no problems.<p>1996 a4 2.8 qm

Bill Shaffer

I had a pair of Tokico shocks on my Honda that were really good. After about 100,000 miles a mechanic told me he thought one was leaking. So, I called Tokico and they said " take them off and send them to us, we'll decide if they are defective". If that's the system for determining your warranty benefits, in my case ,that is no warranty worth having. Still, I would buy aftermarket shocks and consider 100,000 miles to be a good life for a shock.<p>Bill Shaffer

Erik Addy

The Bilsteins still have oil in them. The presurised Nitrogen is to prevent "foaming" of the oil during periods of lots of movements.<br>Koni clames this is no longer nessesary due to advancements in their shock design.<p>Keep in mind that Konis are ajustable, altough you often have to take them off the car. Bilseins can be revalved, but you have to send them back to the factory and pay around $50/shock I think.<p>later,<br>erik

Greg Woo

Herman:<p>Both Bilstein and Koni offer lifetime warranties. Basically, the quality and performance levels of these two manufacturers are nearly identical. Where they differ is the manufacturing process. <p>Bilsteins are typically a high pressure gas, monotube design. The oil in the shock is kept under pressure by a seperate nitrogen gas chamber at the bottom of the shock. <br>This is necessary because as the piston enters the shock tube, it displaces oil. That oil has to go somewhere, so it pushes up against and compress the gas chamber. <br>Bilstein also uses a "deflective disk" piston, aka a shim stack. The piston is the resistance device that moves through the oil.<p>KONIs are twin tube, low pressure gas shocks. Oil and gas are emulsified, i.e. mixed in solution. The gas bells in the oil give the oil a slight bit of "compressability." This means at very high piston rod velocities, but very small stroke distances, the shock oil acts as a cushion, improving ride comfort. KONI uses a system of bleed holes and bypass springs in their piston to generate resistance.<p>There it is: everything you every wanted to know about shocks and a bunch of extra stuff nobody really cares about!<p>Best Regards,<br>greg woo

HermanH

Re: Bilstein Vs. Koni - great explanation. Thanks for correcting me.