Which Coilovers?

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jpr210
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Which Coilovers?

Post by jpr210 »

replacing the shocks in my car and not want to use the usual Bilstein sport solution. Want to have the option of controlling the shock settings and corner weights with coilovers but not want to lower the car much (maybe 1/2"). Has anyone used the GAZ brand? I have heard horror stories of BC and other style centered brands (as opposed to KW, Moton etc.)

Thanks

Jpr
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tschultz
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Re: Which Coilovers?

Post by tschultz »

Have you looked into standard SPAX adjustable shocks? That's would be my choice if I wanted adjustable suspension.

http://www.ebay.com/itm/401071158967?_t ... EBIDX%3AIT
http://www.Drive4Corners.com
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Brucey
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Re: Which Coilovers?

Post by Brucey »

it might help if you say why it is that you think that Bilstein shocks might not suit you, or what kind of driving you want to do with your car, or why you might need/want to be able to adjust your dampers, or what you are hoping to gain by so doing.

IME folk who buy adjustable dampers (for road use) usually get bored of fiddling with them after a short while and then leave them alone, not always on a setting that makes any sense.

If you intend to use damper settings that are a long way from standard, it is as well to note that lots of other suspension parts (bushings, springs, ARBs, geometry) would need to be changed for items that would allow the non-standard damper settings to work properly. Everything needs to be matched.

Note also that the standard setups use the bump stops (external at the rear, internal or external at the front depending on damper type) relatively early in the travel as auxiliary springs/compression dampers. These also have a dramatic effect on the roll stiffness and whether the car understeers or oversteers when you are cornering hard. There are also 'negative springs' (of differing types) in most E24 front shocks; these also affect the roll stiffness. If you fit race-spec dampers then all this would need to be rethought, it isn't just a question of twirling a few adjusters on some aftermarket dampers that have been adapted to fit on an E24.

Probably there are some well-developed E24 suspension setups out there that will give you a few tenths a lap on a racetrack; great! -except that almost without exception, such setups are pretty much unbearable in everyday road use. The various different 'stock' setups (HD, sport, M-car etc) that are available for E24 are each fairly cohesive and make pretty good sense for various different purposes. Realistically, to improve on those would be a lot of work for very little gain IMHO.

A final comment concerns adjustable shocks in general; they almost invariably need to be calibrated. If you get two adjustable shocks out of the box it is extremely unlikely that the same settings on each damper will actually give exactly the same damping; this really needs to be proven on a shock dyno.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
redrumm3
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Re: Which Coilovers?

Post by redrumm3 »

I think Brucey's comments are right on the money. Without knowing exactly what it is you want to do with the car, it is difficult to give you any meaningful advice.

I can say as a general rule, you get what you pay for, when it come to coilovers. I have been running coilover suspensions on my E36 M3 race car for years. Currently, I am running a custom made Bilstein setup. The problem with coilover suspensions is that it opens up so many other variables (spring rates, sway bars, camber, castor, compression and rebound, corner balance, etc.) that it is easy to get lost in the setup and most people actually make the car worse. Its takes a lot of time, test and tune, to really dial-in a coilover setup unless you have the good fortune of having someone's baseline setup as a starting place.

When people ask me about putting coilovers on their car 99% of the time I steer them away from it. A good set of lowering springs and some good quality single adjustable shocks (ie. Koni) usually gets them where they want to be with the car and for a whole lot less money.
Scott Collins
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jpr210
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Joined: Tue Jun 25, 2013 2:27 am
Location: Miami, Fla.

Re: Which Coilovers?

Post by jpr210 »

I have used shocks like the Bilstein sports and others thru the years and the quality of the damping performance is not as good as good coilover setup. having replaced the Koni shocks in a 944 turbo with the 28 series coilover brought about much better body control and less harshness. The Bilstein in my latest project got replaced with KW V3's and the difference was night and day in ride quality and reduction of impact harshness due to the quality of the shock absorber. I'm not looking to turn the M635 into a track car, just want to slightly lower it and get better shocks than the run of mill off the shelf ones.

Jpr
jpr210
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Re: Which Coilovers?

Post by jpr210 »

So, nobody has done this?

Jpr
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BillDe
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Re: Which Coilovers?

Post by BillDe »

viewtopic.php?f=9&t=24110&p=194248&hili ... rs#p194248

Check out this thread, had H&R build coilovers.

Bill
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