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      12-10-2011, 09:13 AM   #45
Orb
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Originally Posted by MDORPHN View Post
Yes, I've spoken to James. He thinks that 350#/600# may be just a bit low, and I've since spoken to a fellow at JRZ USA who said 350#-400# is as low as I should go.

So.... I'm now thinking about going with some 392#/672# Swift springs.

Neil

A 392/672 is going to work well. A slight stiffer rear spring may help give you a better flat ride control on the street but only if you setup the shocks accordingly. The ideal spring lengths are 8" front and 9" in the rear. As general rule, this allow spring to work in droop travel which will be very important for ride qaulity/control on the street. I tried just about every combo of springs over the last 3 years and this is the best one and the calculation matches as well.


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Originally Posted by Pete_vB View Post
So first, I am fairly convinced that rebound and compression are mis-labeled on those graphs. I ran some simulation numbers and came out with rebound higher than compression (which is the norm), so I wouldn't want to read to much into these before that can be double checked.

Second, I'm not surprised the rear is overall stiffer than the front. Assuming the 1M's motion ratios are identical to the M3s (purely an assumption on my part based on what I've read about the M3 and 1M sharing parts) then the rear motion ratio is something like .56 vs a front of .96. This means the rear shocks would need to be much stiffer at the shock itself to have identical values at the wheel. Quick rough simulation suggested rear shocks almost 3x stiffer than the fronts would be about right- these are less than 2x, suggesting they may be softening up the rear (likely both springs and shocks?) to help put power down. Seems to make sense.

Could you post the M3 values you have as well? Any way to double check bounce if and rebound are labeled right?
The rear suspension frequency is variable due to inclination of the spring and artificial spring rate increase due to the spring bending along a curved axis when using 60 mm race springs. The rear suspension frequency will increase about 0.2 – 0.4 Hz from what is calculated through the working range of the suspension. The rate of increase is fairly quick at some points in the stroke so spiking should be expected although not excessive.

As a reference I designed an articulating spring perch that sits between the helper and main spring to combat the spring bending along a curved axis. At full droop the device is tilted about 9 degrees. Having the helper springs on the bottom on the camber link goes along way at reducing stiffness cause by spring bending along a curved axis. The helper spring will translate up 5-7 mm during use.

Last edited by Orb; 02-14-2012 at 02:30 PM.
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      12-11-2011, 08:36 PM   #46
gotboost426
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Moton all day.
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      01-09-2012, 12:46 AM   #47
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Originally Posted by MDORPHN View Post
Thanks.

I ran AST 4200s on my previous car (a much-modified '99 M Coupe) and liked them. Just not sure how their "internals" compared to the Motons.

Neil
Two different technologies, AST uses shim stacks and Moton uses orfice bleed.
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      01-10-2012, 10:46 AM   #48
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Hey so ive notived throughout this whole thread no one has those bilstein coilovers in there. I was told bilsteins are alot better quality and ride then kw coilovers and are the same price range. Im fairly new to suspension modding so im looking between the bilsteins and kws ( pss10s vs v3) i know all the other companies AST JRZ MOTON and ohlins are top of the line and really expensive. I really want a suspension that is going to be really nice for road driving and better then the stock suspension but still comforable

Does any have there .02 on this?

I was looking at a sleeve kit but i want to do the car right and get the damper as well .

So basically whats better quality/ ride and adjustment? Bilstein or KW
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      01-10-2012, 11:58 AM   #49
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Originally Posted by M///1rider View Post
Hey so ive notived throughout this whole thread no one has those bilstein coilovers in there. I was told bilsteins are alot better quality and ride then kw coilovers and are the same price range. Im fairly new to suspension modding so im looking between the bilsteins and kws ( pss10s vs v3) i know all the other companies AST JRZ MOTON and ohlins are top of the line and really expensive. I really want a suspension that is going to be really nice for road driving and better then the stock suspension but still comforable

Does any have there .02 on this?

I was looking at a sleeve kit but i want to do the car right and get the damper as well .

So basically whats better quality/ ride and adjustment? Bilstein or KW
There is also Koni and AST, but the title of the thread is Moton vs KW. Do a search, I am sure you will end up with reviews on the other brands are you after.
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