B serious

BTW, it seems that what a lot of people are missing from their wheel rate logic is thay the car only weighs like 650-700LB per corner all inclusive.


The car's sprung weight is a finite amount at the shock tower. Corner weighting the wheel will sum all the sprung and unsprung weight. The wheel/tyre, half the damper, and the LCA are probably worth like 60LB or so per corner. I believe the brakes and spindle are unsprung as well.

If you're putting 1200Lb of force into the spring via increasing leverage via motion ratio....the spring will only compress until it can lift the sprung weighg. A 450Lb spring will compress 1.25" til it can lift 562LB, for example. The control arm may keep traveling upward...but the chassis will now start to lift as well.

If dampers are mounted off-vertical, their effect becomes lesser. A damper mounted at 30 degrees off-vertical will be easier for the LCA to compress than a damper mounted vertically.

Idk what angle the S2000 dampers are at.

Apex1.0

Well I guess there is what should work (more preload/bump travel), and what we know does work (Ohlins spec). It seems most are using the oem spec and everyone is happy.

I am thinking about splitting the difference. Go around 6-8mm preload and shoot for about .75" of clear piston.

Ohlins USA responded to my email and cited their spec is a suggestion and that many people add preload to these dampers.

B serious

Yeah, .75" to bumpstop may be a good compromise between having enough compression travel vs. rebound travel.

B serious

Are you planning on tracking this car?

noodels

Ohlins USA responded to my email and cited their spec is a suggestion and that many people add preload to these dampers
So +7.5mm<5turns>6mm<4turns>extra preload would be 5 or 4 complete turns,giving 9.5mm or 8mm.<if already at 2mm>
1.5mm per turn,makes it a quick adjustment,
same turns on the bottom to get same ride height/maybe after more preload added..

B serious

Lol. That's kind of a funny reply on Öhlins' part.

Of course its a suggestion. If it wasn't a suggestion, the shock wouldn't have threads on it.

If there was some way to get in touch with an engineer that worked on the product, one may gain some insight as to WHY they chose 2mm. They're not going to give away anything proprietary, but they may be able to tell you some things.

Speculation would say that 2mm provides an acceptable level of comfort and handling and shock travel in both directions, as well as ride height range. I doubt coil bind is an issue even with a ridiculous amount of preload.

But even an engineer likely won't give you the best spec for how YOU drive and use the car. Again...that's why the shocks have threads.

Set the shock to factory spec. Did it work? Great. Leave it. Don't like it, or it doesn't work for you? Set it up some other way.

As long as you're using common sense and heeding manufacturer warnings, you're likely not going to break anything.

Apex1.0

Oh yeah

B serious

You probably wont use much more than 0.6" of shock travel at a relatively smooth track, on street tires. You may momentarily hit bumpstops. No biggie.

I will say that, compared to my KW's, the Öhlins do tend to allow inside wheel spin on sharp corners that I try to dig my way out of. I have mine at 2mm preload.

I am, for that reason, reluctant to go *much* further. Though 10-12mm preload probably wouldn't make it much worse.

andrewhake

You probably wont use much more than 0.6" of shock travel at a relatively smooth track, on street tires. You may momentarily hit bumpstops. No biggie.

I will say that, compared to my KW's, the Öhlins do tend to allow inside wheel spin on sharp corners that I try to dig my way out of. I have mine at 2mm preload.

I am, for that reason, reluctant to go *much* further. Though 10-12mm preload probably wouldn't make it much worse.
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Stiffer rear springs is a good solution to combat all of this stuff. 10kg/10kg with DFVs is quite nice.

Apex1.0

Well it's a street and track car, so I will probably use more travel. However I have never opened the diff with my konis, if that became an issue I would want more droop travel.

Great point on the 10k/10k. I love the 500/500 bias I am running on my konis. That's with 215/245 tires. It's very nuetral and controllable. If my car develops a push, I will be looking for different springs.