Hi all,

I've just placed an order for a set of new BC BR coilovers. just wanted to check if there is any method of running the coilovers in, mainly in regards to damper adjustment.

can i set it to whatever stiffness i like initially, or should i run them on the softest/hardest for a few weeks etc.

thanks all

John

 

We are neither soliciting S2000 suspension business nor do we want it.

This is our primary line of business, suspension - albeit for the BMW and Porsche. We have sold hundreds of kits and race systems worldwide and our vehciles are widely renowned for their prowess and more importantly balance be it road, track or both. However, suspension is suspension so advice here applies to all. Some generalities:

1. If your vehicle is not equipped with monoballs throughout - and if you need to ask, most assuredly it is not - then it will take approximately 200 miles and 2 weeks for your bushings to take a new set. What this means to you is:

A. You MUST torque any joints where bolts are being loosened and retightened - and frankly, any bolts involved in the suspension - with the full weight of the auto resting on them at the new approximate ride heights.

B. Do not be fiddling with ride heights trying to make the vehicle lower unless it is grossly too high as in 0,5 inch or more. The vehicle will continue to take a new set over the course of time and distance. At the same time if the vehicle is too low, it will only get lower so gradually raise the ride height. It is NOT the dampers (rubber eye bushings excluded) nor springs taking a new set (unless it is really a crap system), it is all the rubber bushings throughout the vehicle adapting to the new suspesion's ride height that takes time.

C. Assuming your vehicle had anywhere near a good alignment prior to installing the coilover, do not have it realigned until settling is finished. You're only likely to make the alignment worse as it will be based on a totally and most likely unevenly unsettled suspension.

2. Prior to having your car aligned, get it PROPERLY cornerweighted set for ride height at the same time. This does not mean simply driving it on scales and recording the weights nor does it mean to adjust the ride heights without removing ALL other forms of braces, sway bars in the vehicle, preset damping&C&C. A vehicle without adjustable endlinks properly adjusted and with sways attached will almost always have a 50/50 or thereabout cornerweight irrespective of how far off the rideheights are. If you want a short 1 page paper I have written on proper cornerweighting, send me a PM.

3. MOST but not all (e.g., Bilstein) 1 way adjustable dampers are in the rebound phase for good reason, as it facilitates the usage of a range of spring rates without having to revalve. Do NOT go crazy thinking that a firmer rebound adjustment will bring race car handling to your vehicle. All it will do is overpower your spring and lead to a situation where the auto is riding on the bumpstops after a series of bumps. Sure on billiard board smooth surfaces it may feel more planted if uncomfortable but that is your butt lying to you. There are many good references for adjusting dampers and the KONI and Penske are to my mind the best - again, PM me with your email address and I'll send copies. For clarification, the reason REAL race cars, Open Wheel and Sports Racers ala AUDI/Acura ALMS autos have such stiff suspension is to maintain ride height at a critical level that is necessary for these vehicles to produce multiple G cornering. Were it legal and possible to have an active suspension such that these heights and damping could actively adjust on the fly, they would and speeds would be even crazier than now. A properly adjusted suspension on a non aerodynamically dependent auto SHOULD be just supple enough to absorb road irregularities without the tyre having to lose contact with the surface. Thus a street driven auto in Georgia can run a significantly stiffer spring and associated damping than one in New York or Toronto, comfort of course is an issue and varies with the person. Where the Georgia driver has an advantage is that one can use the stiffer spring rate to get some advantage in limiting body movement under track conditions of braking, cornering and associated body roll, pitch&c and in particular with much less discomfort than the driver on poor road surfaces. This ability to chose a proper spring rate for your driving location, venue and preferred comfort level is a nice to have benefit and differentiates good from one size fits all "systems" BUT it is NOT end of the world and can be worked around. Of course race systems are all planned bottom-up with various differing components for different venues (assuming a non suspension spec series), compromise and having a team to execute the changes needed between events not being an issue.

4. At least per the KONI, Ohlins, AST and Penske engineers I have worked and talked with on this issue, there is no break-in period for suspension damping - thus a good setting is a good setting from the damper's perspective.

I am always amazed suspensions come with such terrible and incomplete literature and instructions (when they come with any at all). Our guys get about 30 pages of information on all facets when they buy from us but all of it is assembled by us with input from the manufacturers and unforyunately not from the manufacturers themselves directly. Of course, the race stuff isn't as critical to have such documentation, as ostensibly racers know what they're doing but most amateurs rarely get anywhere near the potential out of their suspensions. Truth be told, at least 2 top pro teams I have worked with are in the same boat (I was hired as a crew member and not suspension engineer but the data traces and driver comments (and lack of performance) made it painfully obvious what was going on). Please, those with S2000 suspension business interests and sponsors to pay off, don't be triffling as this is not meant to be a detailed technical discussion on suspension theory and adjustment but rather a quick and dirty guide for those new to the subject from a guy without a commercial interest in giving it to this audience. The guy has already purchased what he's using and there's no sense in torturing him over how he should have purchased X,Y or Z system....

Dan Law
dermotorsports@gmail.com

 

You can set the damper settings at any time to whatever you want within the manufacturer's adjustment.

 

appreciate the post mate! will take that into note when setting mine up

 

hm. Sounds good, man. Its actually a good read. Thanks for the post

 

Ya just never know who you will run into or what bits of useful data you will pick up here in the world's biggest S2K garage.