THSCC Forums

I'm considering upgrading to an adjustable suspension for the VW. I like the potential of adjustability and ride-height control, but i am somewhat wary of making the ride too rough. I suspect that any aftermarket coil-overs will result in a stiffer ride than the factory setup (which is already fairly stiff), even on the softest settings, and being my daily driver, I don't want to take too much of a beating on rough roads.

Now that I do have a set of dedicated wheels/tires for autocross use, could the use of daily driver tires with higher sidewalls compensate for any ride comfort lost from the aftermarket springs? Right now I am running 225/40/18. Would an increase to 225/45 (along with a change to less performance oriented tires) smooth things out a bit?

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Apparently, I'm the resident VW apologist.

generally speaking when you increase shock/spring stiffness you will have to deal with a more harsh ride. I went up substantially in stiffness and though its more firm, its very doable for me. That being said, every person and car is different. If you can find someone who has a similar setup to what you are looking for, I suggest doing a ride along. Thats going to be the best way to decide if you can live with it on the street.

As far as tires, you can always go up in size but the amount of drop you give your car will determine the sidewall and/or width of your tire.

sadly if you need a more specific answer, you will likely have to check what your cars community has to say/suggest.

Have you looked at just upgrading swaybars as opposed to changing coils? This generally causes less of a ride penalty. Being a FWDish car, do you have an upgraded rear sway bar? If not, I highly recommend you start there rather than springs/coilovers. Koni yellows are a good handling upgrade as well without a huge ride penalty which can then be set to full stiff for autocross and impart a handling advantage as well. They are a bit stiffer in compression, but keeping the rebound damping soft (which is all that adjusts on yellows) for the street gives a reasonable ride, while jacking it up does tend to increase roll stiffness for autocross). You'll need to double check that you have the ability to adjust them on your application while still on the car though (and the 3, you have to remove the rear shocks to adjust them which defeats the purpose somewhat).

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2012 MX-5 Sport SUV

If the shock valving matches your spring rates, you'll hardly notice a difference. The S2000 has 900/800 with shocks set up for those rates and the ride is perfectly fine (as in, not noticeably different from OEM ride quality) when shocks are set in the middle or toward the softer settings. When cranked up (ie, when I forget to soften them for the ride home )then yes, the ride is harsh...but that's the advantage of adjustability. In contrast, the Bilsteins I have on the WRX were put on back when I was driving in DS, and were too firm for the OEM spring rates as the shocks were designed for aftermarket stiffer springs. The ride indeed has a bit more jounce, but it performed much better in an autocross setting.

+1 on Brice's suggestion for incrementalism. I did that with my car, and it has been very educational seeing how each component adds to the handling characteristic of the car.

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Steve Carter
1972 Datsun 240Z-- resto pics at http://picasaweb.google.com/srcartermd
2007 GPW Honda S2000-- STR 86

Sidewalls, sidewalls, sidewalls.

On my 215/40/17 tires its bone crushing (just ask Vincent)
On my 205/50/15 tires its Cadillac style, well at least compared to ^

Higher end shocks with nice, wide range of adjustablility help too.

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02 Focus SVT
STF 9

No doubt! With no sidewall you could get super soft springs and shocks and still rattle your teeth loose.

I'm sure some will disagree, but a great ride and great handling are mutually exclusive in my experience.

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Vincent Keene
'06 Ford Mustang GT (track rat)
'15 Dodge Charger R/T (yeah, it's got a HEMI!)
'07 Ford Fusion SE (205,000 miles and counting)
'98 Chevy Z-24 (retired)
'93 Acura Integra (Team SWB 24HOL Car)

You just need to get a BMW Vincent, they have that great ride/great handling thing down pat. . .

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2012 MX-5 Sport SUV

Haven't tried them myself, but Koni makes a 'FSD' line of shocks that are supposed to improve handling without sacrificing the ride quality. Tire Rack did a review of them on a 3 series, may be worth checking out.

http://www.tirerack.com/suspension/tests/koni_fsd.jsp
http://www.koni-na.com/fsdeibach.cfm

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2014 Rally-X VP
'96 VW GTI VR6 Multi-Xer
'91 BMW 318is
'97 Ford F-250
'12 Mazda3

Koni Yellows (sport) didn't really "impact" the ride comfort of my Mustang but the springs are still stock. Koni indicates that a lot of the time oem bump is actually firmer than Koni uses in the SA Sports. Even with the shocks set moderately firm and 35 series ZII's versus the oem all season 50 series Kelly hasn't complained . . . yet (we will see what she thinks after we drive through Richmond to an EVO TnT this Saturday.)

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Dick Rasmussen

FS 50 2018 Mustang GT

I see you ran in BSP in your last event. If you haven't changed the suspension yet, are you there because you are running wider-than-stock wheels, or you've made some powertrain mods? Brice's suggestion about a new rear sway bar and Koni yellows makes a lot of sense if you're still in stock...er... street class, but if you're going to stay in BSP, then you might as well bite the bullet and do everything else the rulebook allows, and buy another car for daily driving and trips with civilian passengers.

Going to stiffer springs will make the ride firmer and (depending on how brilliant your shock valving is) more jiggly. What will really ruin your ride is urethane bushings on your control arms and upper strut mounts, or worse yet, upper strut mounts utilizing spherical balls. You can try taller/softer tires, but road impacts will come through anyway.

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Art McDonald
Premier Amateur #518
2008 Dishman Cup
Pivot Cone Snob

Rodney is a waxer (but in a good way)

600# front springs in the Miata are surprisingly good with the revalved Bilstiens on it. It really comes down to having a high quality shock with very good valving. Washboarding is miserable though.

Right now, I have upgraded the rear sway bar, dropped from 18 x 8 to 17x 8 wheels, and added an ECU tune (the sole reason I am running BSP). The tune is switchable, so I can still run DS at any time. For the most part, however, I am not to worried about my pax, and am fine to run BSP. I suppose I might try to run DS at NCAC. On the other hand, staying in BSP would leave me a lot of places to go.

Having just finished my first track weekend, the car has a high COG and a large amount of body roll. Managing this and weight transfer was a big point of focus. One of my instructors pointed out that I was actually contributing to the weight transfer by allowing the chassis to gain momentum during side to side transitions, and I needed to smooth those out and give the car a moment to settle. I think suspension could improve this somewhat, but looking at some photos from the event, I needed every inch of clearance I had for the tires. Are cross braces permitted in BSP?

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Apparently, I'm the resident VW apologist.

Cross bracing has a minimal impact on roll stiffness compared to springs and bars, and will have no effect on total weight transfer, likely increasing it as you are adding to the sprung weight of the car. IIRC, subframe connectors are *SP legal, I assume SFCs and crossbraces are synonyms, but I don't know for sure.

Edit: I am unclear as to what you want to do...do you want to decrease total weight transfer, or do you want to better control how your car responds to the weight transfer? Both?

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Steve Carter
1972 Datsun 240Z-- resto pics at http://picasaweb.google.com/srcartermd
2007 GPW Honda S2000-- STR 86

FYI: My 2012 Mustang has Koni Sport (Yellow) with stock springs and front bar. Dunlop ZII tires. With the shocks set to full soft the ride is no worse that stock shocks and maybe better even with the ZII's compared to the soft oem all seasons. With the shocks at essentially full stiff and the tires at 40 psi hot the ride is "NOT" soft. Even mid range on the shocks is stiff riding, especially with the tires at mid 40's hot. With the shocks set firm and the adjustable rear bar a little stiffer than stock the car worked pretty well . . . as long as I don't compare it with the CM Formula Ford. That said, over 30 runs with many of them back to back with no complaints. Can't do that with a formula car.

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Dick Rasmussen

FS 50 2018 Mustang GT

Learn how to drive the car with it's current suspension and control the momentum. Maybe upgrade the dampers to an OTS package. Throwing money at getting a stiff suspension will solve your body roll issues; however, you're going to reduce the amount of margin you have for controlling the momentum.

Modifications to your driving style are free.