As most of you know, the S2000's shocks are produced by Showa, and the rears have external reservoirs. Why do most aftermarket shocks as well as coilovers not have the reservoirs? Do they have higher performance products without having to have an external reservoir? For example, the Tein type Flex coilover system does not have this, as well as a lot of other well known brands. The only coilover and shock setups for the s2000 that posess external reservoirs are high end ones (i.e. Toda, Moton, JRZ, ect.) Why is this? Does buying aftermarket shocks constitute a demotion in performance compared to the stock ones?

 

These affordable coilovers have external reservoirs on all four corners: http://marketplace.s2ki.com/s2ki/product.p...7&cat=12&page=1

As a matter of fact, the other German brands of coilovers have them at least in the rear as well (Bilstein, H&R). As to why the hyped up brands don't, I have no idea...maybe because engineering is less important than green paint

 

The external reservoir provides better cooling -> more fluid + larger area to dissipate heat. This will provide better performance (consistent temp = consistent damping) and durability.

As to why some manufacturers choose to use it, while others don't is a mystery to me!

 

BUT IT'S JDM, y0!

 

Maybe due to less suspension travel resulting in less fluid to be displaced?

 

I was only slightly trying to be facetious but the engineering reasons for the remote reservoirs are to allow not only for more fluid capacity for cooling as was stated above, but also to permit the maximum suspension travel. In the rear of the S2000 especially, travel is severely limited by the available shock length. In order to maximize that travel, the Honda engineers wisely chose an external reservoir design for the shocks; this in turn allowed them to tune damping and spring rates so that the car is compliant and doesn't require jawbreaking spring rates to keep the shock from bottoming out. This is even more important when the car is lowered.

The European manufacturers, who actually have to pass rigorous testing before their products can even be sold in some countries (similar to CARB certification for engine parts in California but this applies to everything, even bodykits), have designed their suspensions with external reservoirs for the very same reasons that Honda saw fit to spec them for the stock suspension. It allows reasonable spring rates for the street while still allowing precise control of suspension movement by optimizing damping curves. The only reason I can think of why some manufacturers choose not to do this and instead just slap on the stiffest springs they can find is simply they don't want to invest the time and energy to actually engineer a solution. But what do I know

 

...and maybe because for street applications, it's not really necessary. Look at the really high end cars like Ferraris, porsches, the new Z06, etc. None (or few) of them have external reserviors from the factory and most of the aftermarket stuff, barring full race shocks (and even some that are full race) don't have them. My guess is that other than in severe duty like constant racing, remote reserviors are just not necessary. It would be one hell of a paved road that could heat a shock enough to fade it. I am certainly not an expert in the S2000 suspension, so I don't know what decision/compromise/etc. was made by Honda when designing the OEM rear suspension, but it might just be that the mid-end aftermarket systems are designed well enough (instead of poorly enough) that they don't require reserviors. Happily willing to be wrong on this, but I did stay at a Holliday Inn last night...

 

if you like oem reliability+reservoir, then buy the spoon coilovers. They are made by Showa to spoon's specs to accomodate stiffer spring rates.

 

The Teins that are comparable in quality to the KW's do have external res and the cool green paint. The RS and the new SRC both have external res and adjustable for both rebound and compression. The SRC seems to have gotten pretty good reviews so far.

 

JDM vs The Rest of the World .. ....