EVO8LTW

iTrader: (41)

I was just wondering how much of a factor monotube vs. twin tube construction should be in choosing a coilover. In general, I understand that monotubes (like Bilsteins and Ohlins) are better in many respects (heat dissipation, weight, consistency of response, etc.) and generally regarded as superior technology to older twin tube designs, but that twin tube design enable less expensive coilovers (like KW Variant 3s) to have compression adjustability.

Any thoughts on how much weight should be placed on the monotube vs. twin tube design in selecting a coilover in the $1800-3000 range?

Thanks!

DaWorstPlaya

iTrader: (31)

Without going into too much detail, it really depends on the quality of construction of the particular coilover and what you are looking for. Some of the advantages you listed above, better heat dissipation, weight and consistency of response are true but don't necessarily apply to all twin or monotubes.

Monotube can be more fragile, meaning if the body of the shock gets a little nick or ding, the shock will be damaged and essentially become a large paper weight. Twintubes in this respect are more durable. But since twin tube have the extra layer of insulation they might suffer from over heating and oil cavitation. Which would then lead to inconsistent performance. But supposedly KWs uses a special oil that is more heat resistant and does not suffer from this effect, leading to more consistent performance under extreme conditions. Twin tubes are also generally cheaper to produce in comparison.

The simpler design of monotube supposedly helps it react quicker but a lot of that can depend on the valving and its design. A well designed valving system will help the shock react to the various forces quickly in the correct manner. With a well designed valve, twintubes can also react quickly and correctly. Then difference in reaction of the shock can be like splitting strands of hair, meaning the differences may not even be noticable to the driver. Only on the shock dyno will you notice the difference. As they say, the magic lies in the dampers.

If you are looking for coilovers in the $1800-3000 price range there is always going to be some compromise somewhere.

You can get 2 way adjustable twin tubes of very high construction quality and high materials quality but without seperate height adjustment. Meaning the height adjustment will also affect spring preload (aka KW V3).

You can get 1 way adjustable monotube with high construction quality but average materials quality without seperate height adjustment (aka Bilsteins). I say average materials quality because unlike other shocks made of stainless steel and aluminum, the Bilsteins PSS9s are made of regular steel = rust over time. Same issue with height adjustment and spring preload being combined. Which also happens to be the cheapest of the bunch.

You can also get 1 way adjustable monotube with high construction quality, high materials quality but slightly older valving design without seperate height adjustment (aka Ohlins R&T or Sportlines). These shocks use a slightly older valving technology compared to some of the newer offering by Ohlins. Same thing with height adjustment and spring preload.

What I'm trying to say is, in that price range, there is always a compromise to be made one way or another. If you want seperate height adjust and spring preload, 2 way or more adjustable, high construction quality, high materials quality, more advanced valve design then you have to be willing to pay more. In that price range, pick whatever you are willing to live with. BTW this really should be in the advanced forum .... just a thought.

Noob4life

True, but this is also good info for anyone! Good comparisons and summary.