Arnie

I am very interested in Whiteline's new Group 4 coilovers and I've been mailing a bit with Jim Gurieff of Whiteline to get more info on their recommended setup.

I have never had a coilover setup on my car though I've installed a few and ridden a bit on a few. Hopefully I will have these on my car soon so that I can provide a consumer review in addition to Pam's (Renick) initial impressions.

Anyway, I asked Jim if he had any recommendations on ride height, damper rates, alignment and so on. His response was a bit more general (and for some on this board, controversial) than I would have wanted but I understand their legal position. However, his statements on basic set-up ring very true with what I've suspected and on occasion, experienced in my various suspension forays.

Arnie

Questions Re: setting up of Group 4 coil-overs.

These are all valid questions but are difficult for us to answer because there is little objective truth in any of this. More so than any other product, the correct answer depends on intended use, related
componentry, driving styles etc. The fact is that coil-overs have moved from the highly specialised suspension tuning area (originally designed PURELY for race use) to the realm of fashion. Evidence to this is the fact that MOST coil-overs currently sold have height adjustment but no damping rate adjustment, how crazy is that?

Being a fashion item; it is being bought by people that have next to no idea about what they are doing, having it fitted by general mechanics or suspension people that have only a little more knowledge. They think it's a simple matter of slamming for the weekend car show then jacking it back up for mid-week. What about the wheel alignment to deal with the dramatic resultant toe and camber change? What about the screwed up weight distribution and handling bias when they try to "even out" the guard (fender) clearance front to back even though the front wheel arches are taller than the rear to begin with?

OK, we're living in the real world so Whiteline cannot take a position on recommended height or adjustments for this stuff as it implies that it is universal, objective and recommended, which it is not. We want to be sure that our customers are 100% certain that this kit (respectively, all coil-overs) is NOT a toy, that it requires a deep understanding of suspension setup and that to do otherwise can create some major drivability problems and adversely effect safety (and performance). Even if we wanted to, legally we have no choice but to take this stance as fitment of coil-overs is technically illegal in many markets.

Please have a look at the fitting instructions we have loaded on to the website at http://www.whiteline.com.au/fittingsheets.htm . There is a generic Group 4 set of instructions that need to be supplemented with others specific to each kit part number. The contents are carefully put together to reflect our position with this product. It should basically convey the message that if you need to know what bolt to undo to fit this stuff, you shouldn't be touching it in the first place. Even if you have fitted it, we can not give advice or specific guidance on height or rates apart from saying that you should always start higher and softer rather than the either way round. If we have to do some generic advice for performance handling outcomes it would be:

Height::

Less (height change) is more unless you are using purely for track work. Driving surface quality is directly related to optimum ride height. The poorer the average surface the greater the need for suspension travel. Follow the leads of any reputable lowering spring supplier and only lower according to their standard options. That is, if a Control solution lowers a standard WRX 30 mm then follow the same. Fitment of a coil-over does not miraculously change the laws of physics and means that you suddenly need less suspension travel. Sure, our Group 4 coil-overs are designed to have more suspension bump travel than standard shocks but excessive lowering is still excessive.

Spring rate:

Though not adjustable, the essence of a coil-over is tune-ability and that includes using standardized race style coils that can easily be changed for height and spring rate. We provide a variety of recipes to suit specific purposes like street/race, drag or drift to name a few. The kits are marketed in turn for each specialty with the spring recipe to suit. The specific rates used in each kit are a very good start with an appropriate front to rear bias built in. (Rates published in fitting instructions.) Again, changes to spring rates and bias are a very powerful and dangerous tool.

Arnie

Height bias or rake:

If in doubt (or unless you really know what you are doing), always change the height in the same proportions front to rear. The factory has provided a particular bias for good reason and you need to know the outcome of any change to this BEFORE you do it. For example, a neutral steering car can become an understeering and oversteering handful if the front is excessively lowered to match the rear guard gap.

Shock rate:

Though principally adjusted to match spring rate, this almost always should include other things like uprated swaybars, tyre construction and pressures, non-compliant bushes and a myriad of other variables. Assuming that only the springs and shocks were changed, the shock rate adjustment should be ideally used to control the spring oscillations and that's it. Always start with the softest rate and progressively increase until you control the springs oscillations (similar to adjusting any shock absorber). As with any of the previous, inappropriate use of the adjusters can also lead to erratic and potentially dangerous dynamic behaviour but it's another very powerful tuning tool.

Wheel alignment:

It is rare that the static ride height of a modern car can be changed with out requiring a wheel alignment. At best, toe will need to be adjusted but in most strut-based cars, both camber and toe will change significantly enough to warrant a wheel alignment. That includes the front and rear wheels. This should automatically ring alarm bells for anyone raising and lowering their car on demand. Its OK for show cars but you can't expect good performance if the camber and toe changes by significant amounts with out adjustment. Again, fitment of a coil-over does not change the basic demands of appropriate alignment settings to match tyres, spring rates etc. These are the main determiners to appropriate settings, not the fact that the springs and shocks are now in a "coil-over" configuration. Follow the normal recommendations to begin with then be prepared to monitor and fine tune.

That's about it I think. Its longer than I thought but not as application specific as you might have liked but that's all we can do for the reasons explained. I don't have a problem with you forwarding the above to lists or forums.

Cheers
Jim

Arnie

So my plans are to set-up the ride height as close as possible to my STi Genome setup, which is about 3/4" lower all around, and go from there. Yup uneven fender gap!

As an aside, I once had the opportunity to swap out the rear springs on my RS for even fender gap springs and was very surprised at the outcome. I had Whiteline springs on my car and had the uneven, with perhaps a bit too low rear bias. I contacted Whiteline and asked if they had something that would give me more even fender gap. They sent me a set of rear springs that were a bit taller than what I had, they were the same rate. After installing them I loved how the car looked. Nice even fender gaps! Guess what? It handled worse! I had shifted the weight balance forward, brought the rear roll center up too high in relation to the front and the car felt like it was tipping over into a turn. Where before the car felt planted and the rear squated down into a turn, it now felt like it toppled into each curve.

Anyway, i have been very satisfied with the balance of the STi setup and plan on staying with Subaru's obviously fully researched ride heights and rake.