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Old 04-16-2004, 09:51 PM   #1
Arnie
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Thumbs up Coilover Set-up and Whiteline's take

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.

Here's his response:

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.

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
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Old 04-16-2004, 10:01 PM   #2
Arnie
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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.

Last edited by Arnie; 04-16-2004 at 11:11 PM.
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Old 04-16-2004, 10:19 PM   #3
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I don't see why this should be at all controversial...it sounds pretty much spot-on to me.

Maybe the part about people putting on coilovers as bling-mods...but that's also the truth.
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Old 04-16-2004, 11:06 PM   #4
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I suppose what might be controversial is ride height/rake section. Most here are just obsessed with even fender gaps and getting the car low and very few ever discuss the ill effects of such. Most are pretty satisfied with a lower center of gravity, no fender gap and a rock hard suspension.

So I'm very excited to get a set on my car to see how supple these dogs really are. I've personally always hated the rock hard japanese coilover setups like JIC, TEIN or Cusco. God, who needs 400-600lb/ft springs (with equally hard damping rates) on a road going car? I just cringe at the thought of that. But I'm usually loath to speak out too strongly on those setups because I really don't have much track/road experience comparing all those setups. i've just ridden in a few and thought, damn, i could not drive to denver and back from LA in these. ouch. I dunno, this ain't sex here, harder is not always better.
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Old 04-16-2004, 11:19 PM   #5
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As always Jim from whiteline gives you the answers.

I don't know of any other suspension people who have given us so detailed answers both thru email or their website.

I've used their stuff for over 30 years.(I used to live in Australia)

I trust their stuff as I know their research practices.

End of sales pitch

FWIW
Jim and I don't get on well but I like Whiteline stuff.
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Old 04-16-2004, 11:22 PM   #6
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Quote:
Originally posted by Wombat North

FWIW
Jim and I don't get on well but I like Whiteline stuff.
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Old 04-17-2004, 02:01 PM   #7
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My only comment/question is this:

Why do one of the most highly regarded spring sets for the WRX (Prodrive) drop the front more than the rear of the car? The Prodrives drop the front about an inch more than the rear, but yet everyone seems to like they way they handle.

It does appear that most of the stiffer Subaru setups (STi setups) do keep the height balance closer to stock.
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Old 04-17-2004, 02:52 PM   #8
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Quote:
Originally posted by drees
My only comment/question is this:

Why do one of the most highly regarded spring sets for the WRX (Prodrive) drop the front more than the rear of the car? The Prodrives drop the front about an inch more than the rear, but yet everyone seems to like they way they handle.

It does appear that most of the stiffer Subaru setups (STi setups) do keep the height balance closer to stock.
And that is an excellent question.

We were discussing this last night, the fact that most people out there buying coilovers...

A) Do not need them and will never use them to their potential.
B) Have no fawking clues as to what they are getting into.
The fact that every time you play with the height would warrant an alignment in enough to push me away. What about setting the dampening/spring rates, and balncing the weight equally for the car?

These are not plug & play items and they are expensive.

I am very happy with my Eibachs and Konis, who cares about equal wheel gap?

Steve..
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Old 04-17-2004, 03:30 PM   #9
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My question wasn't really questioning the logic of choosing coil-overs, I think that Jim's argument summed it up quite nicely.

I'm more curious about the type of drop Prodrove chose with their springs which dropped the front more than the rear, something that Jim says above is a big no-no. Looking at pics of other WRXs with Whiteline springs it appears they kept the drop front/rear similar as well.

One thing that people forget when going for that "even" look is that dropping the front more reduces caster. Dropping the front by 1" more than the rear reduces caster by a bit more than .5*.
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Old 04-18-2004, 08:02 PM   #10
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G'day everyone,

I see that Arnie has kindly forwarded a copy of our recent discussion on coil-overs etc.

Though I did say that I didnt mind if he passed this on to forums etc, I do feel a little embarrassed about the comments on some coil-over buyers. I guess I was on my "soap-box" somewhat as we'd been getting a number of enquiry's from potential Group 4 customers primarily concerned with how much they would lower their car then getting upset over the retail price when compared to "other" brands.

Anyway, my apologies if we offended anyone on the forum but we do participate more regular on this and a handful of other forums because of the technical nature of the content. We very much enjoy participating and talking to you guys, just wish we had more time and people sometimes.

Wombat North, thanks so much for the positive comments but you've got me thinking about who you might be. I'll contact you off list.

Drees, that's a great point you raise. Our Control and Flatout solutions actually lower the front disproportionately more than the rear by about 5-10 mm. We do that to sharpen the initial bight in turns while delivering a little more neutral steer with a slight tail-up attitude. Our experience is that most aftermarket spring suppliers do same but to varying degrees. Now, with out getting too controversial, we can not see why anyone would offer to lower the front more than the rear by 25mm unless it was for cosmetic reasons. These companies are highly reputable with a distinguished name and huge engineering resources, they undoubtedly know more about this stuff than we do but we can't understand why they do it as this is excessive rake in our view. We're open to learn more and be proven wrong.

Mr. Hanky, you raised a good point about weight balancing. In my rush to write the response to Arnie, I realise now that I left out one of the most important reasons for the existence of coil-overs and their application to racing. That is, the ability to balance and adjust corner weights. Diagonal weight balance is critical for turn-in and overall balance and is separate to front/rear bias. Race teams spend a lot of time moving things around and adjusting individual corner heights with the help of corner weight scales to deal with these issues.

Thanks again everyone for your understanding.

Best

Jim Gurieff

Whiteline
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Old 04-18-2004, 09:57 PM   #11
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Thanks Jim, always nice to learn something on the boards, glad you took the time to clear some things up.

Steve..
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Old 04-18-2004, 10:24 PM   #12
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Hi Jim,

Thanks for your comments, I don't think that many here will find your comments controversial, but most will find them spot on!

Thanks for your input on how rake can affect handling. However, I don't know of any manufacturers who drop the front by more than 25mm, so I guess they're all safe.

Cheers,
Dave
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Old 04-18-2004, 11:17 PM   #13
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Sorry Jim! Don't mean to get you in trouble with the tuning aestheticists out there! I, for one, do not find your comments preachy in any sense. Perhaps because I agree wholeheartedly with your position. I do think its important that people know the realities and potential liabilities of playing with coilovers. At the least, for those of us out there that are really concerned about how the car handles and learning about the components and dynamics that affect this, your comments are informative and for some, eye opening.
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Old 04-19-2004, 03:03 AM   #14
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Default Re: Coilover Set-up and Whiteline's take

Quote:
Originally posted by Arnie
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.
[sub-concious] ...get coilovers.... sell current set-up to slvrwgn [/sub-concious]
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Old 04-19-2004, 11:00 PM   #15
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Drees,

You originally mentioned that;

"The Prodrives drop the front about an inch more than the rear, but yet everyone seems to like they way they handle."

... hence my answer, 25mm (1") bias change is excessive in our view.

Cheers

Jim

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Old 04-20-2004, 01:14 AM   #16
drees
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I'll have to validate the drop of the Prodrives just to make sure that I've got their specs right, (seems to vary between 1.1" lower front and 1.5" front and .5"-1" lower rear or 12-25mm difference) but you said "we can not see why anyone would offer to lower the front more than the rear by 25mm unless it was for cosmetic reasons", hence my response earlier.
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Old 04-20-2004, 08:32 AM   #17
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On my sedan, the Prodrive springs in front allow the car to sit precisely 12mm lower than the rear.

Let's get real, here. Every modern company must account for the cosmetic tastes of the market as they design their products. To suggest otherwise is silly. Some lean more towards form over function, and some towards function over form -- but they ALL need their products to 'show' well.

I have Whiteline and Prodrive products on my car and they jointly increase the handling AND looks of the car over the stock components. Both companies make quality parts that do precisely what they claim to do.

I happen to agree with Jim's assessments on coilovers and their complexity. Oddly enough, this is why I chose to go with springs, SA Konis, and camber plates. I gained many of the handling benefits of a coilover without the additional complexity of bound/variable ride height/corner weighting.

Of course, I didn't get all the patented coilover bling, either.

Scott
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Old 04-20-2004, 10:46 AM   #18
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Quote:
Originally posted by sdecker
On my sedan, the Prodrive springs in front allow the car to sit precisely 12mm lower than the rear.
Thanks for your input, sdecker. So that means that Prodrive's drop is very similar to Whitelines, throwing my statements right out the window.
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Old 04-20-2004, 11:02 AM   #19
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Quote:
Originally posted by drees
Thanks for your input, sdecker. So that means that Prodrive's drop is very similar to Whitelines, throwing my statements right out the window.
Hey, no problem. I like both of their products and sincerely hope they will each send me their complete catalog for testing purposes. Yeah, that's it...testing purposes.

Scott
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Old 04-20-2004, 11:10 AM   #20
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Quote:
Originally posted by sdecker
Hey, no problem. I like both of their products and sincerely hope they will each send me their complete catalog for testing purposes. Yeah, that's it...testing purposes.
LOL, yeah! Can't argue with that! Whiteline's got one of the best vendor internet presences out there, too. Always sharing their knowledge of suspensions and not afraid to admit they may have more to learn!
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