Suspension setup

[ITSME4G63]

Hey guys, I was thinking about getting a new suspension setup for my car. I want somethign stiff, that wont give me body roll. But I dont want to be lower more than 1" than stock springs. Would a einbach pro kit and some agx's do it? Any reasonably priced suspension setup people can vouch for? I dont want a 1200$ tein one, thats too much money for me.

 

[ITSME4G63]

oley?

 

[emitsu97]

I've been trying to find something with a minimal drop but better/stiffer ride. The closest that I've found is a set of Tein SS and just reduce the default drop to it's maximum height which is still lower than stock. I am curious though, on a 100% street driven car, exactly how important is it to have stiffer springs? My biggest concern is with the potholes I have in my area. It's not uncommon to see one foot deep caverns scattered all about the road. My daily commute looks like everyone and their grandma is running a coned road coarse.

With regard to pricing, the SS aren't that much more considering that you get height and rebound/dampening adjustability plus the springs and shocks are matched in performance. I believe sagging isn't an issue either.

 

[ITSME4G63]

damn YOu are in the same ballpark as me.

 

[97TSIAWD]

Well I have the Eibach pro-kit on my car, maximum drop is listed at 1.3" it is not a crazy difference, there is still a little wheel gap with my 17's but not a lot. The car rides and handles amazing with these springs, imo. I then purchased the Tokico 5-way adjustables from RRE for a good price, and when I stiffened them up I got a better launch with less bucking and sea-sawing. Also the car handles very well in corners, with a good race seat I'm sure nothing but change would be rolling around in hard turns, my body not the cars seems to shift when taking a corner hard. Hope that helps, hopefully someone with a different setup will chime in.

 

[ACM]

I've been trying to find something with a minimal drop but better/stiffer ride. The closest that I've found is a set of Tein SS and just reduce the default drop to it's maximum height which is still lower than stock. I am curious though, on a 100% street driven car, exactly how important is it to have stiffer springs? My biggest concern is with the potholes I have in my area. It's not uncommon to see one foot deep caverns scattered all about the road. My daily commute looks like everyone and their grandma is running a coned road coarse.

Springs aren't the problem when it comes to pot holes, it's the dampers, or more specifically their high speed compression curve.

That said, whilst I know my Shocktek Bilsteins and 700lb springs are more than up Boston pot holes even with < 100mm sidewalls, they're no longer available.

Perhaps that should be your next DSM project DG, excellent dampers to go with your excellent coilovers ?


Charles

 

[DG-FNR]

Perhaps that should be your next DSM project DG, excellent dampers to go with your excellent coilovers ?

In the pipeline. At least, in MY pipeline. The boss has a C5 fetish and that keeps me busy.

I have some roughed-in CAD models of mounts to fit Bilstein NASCAR shocks to a 2G. In order to get them built though, somebody would probably have to pony up in advance, and we're looking at $2500-ish for a full car.

Where the cost is isn't the shocks so much as it is the mounts. Real Race Car Shocks fit 1/2" eye to 1/2" eye. The body lengths and diameters and valvings change from application to application, but there's no _technology_ difference between a Winston Cup shock and an Indycar shock and a LeMans Prototype shocks.

Those of us in the business of racing modified production cars aren't quite so lucky as to have standard shock fitments. The 2G has (effectively) 12mm through-bushings on the top of its shocks, and then a 43mm socket on the lower fronts, and a 20mm single-shear post on the lower rears. Bleah!

So you wind up having to build special adaptors than transform the mount points on the car to 1/2" eye on one end and the native shock shaft thread on the other. That's 2 custom machined bits per corner, with little in the way of economies of scale to leverage.

It's not at all out of the question to figure $300-$500 in adaptor hardware PER CORNER to get real race shocks in there - and we haven't even got shocks yet.

The good news though is that once the adaptors are in your hands, you never need to buy them again. Change shock brands and the adaptors stay the same. This is better than what ShockTek was doing, which was modifying the actual shocks themselves to fit the OEM fitment. Same initial price, and then if the shock is ever damaged, you're SOL.

So in any case, yes, it's entirely doable, and I'd leap at the chance to build a set for sombody. They'd get some really cool stuff; easily the best DSM suspension ever built. But if you're the type of guy to scour EBAY looking for a $5 price break on a coilover sleeve.... other vendors beckon.

DG

Learn: http://autocross.dsm.org/books.html

 

[emitsu97]

For the sake of the OP and myself, what would be a suitable setup for our particular conditions? I know I'm personally not looking for racecar handling but would like a sportier feel without having to worry about harsh ride. I'm getting new wheels this spring, ADR Kasai's 17x8, +35mm offset with 235/45/17 Yoko AVS ES100's. I didn't want to drop for fear of rubbing AND because of potholes, driveways, speedbumps/dips, and so on. I thought ideally I could just get Illuminas set 3 in front and 2 in rear used with the stock springs to maintain the stock height. My concern is that I might be loosing something if I don't get aftermarket springs too. If that's the case I was going to go with the Tein SS's so that everything would work perfectly together and I coudl fool with the height. Opinions? Comments? Suggestions? All very much appreciated.

 

[ACM]

If you are seriously thinking about this DG, I'd love to chat about it. I've picked up a fair bit of data along the way.

Real race car shocks are all well and good, but most people aren't will ing to spend that much - at least not all at once, up front. I have some ideas here, dating back to my FOX experiments.

I'll email you with something intelligible when the next Percocet wears off


Charles

 

[DG-FNR]

For 99% of the people out there, a Koni Sport coilover setup is exactly what you need.

Konis are decent high-performance street shocks. They're not great when compared to Bilsteins or Penskes, and getting them serviced or revalved sucks, but the quality is good, the durability is good, and they fit right up.

The differences between "street" and "race" shocks are, in a nutshell:

- race shocks have no rubber in the mounts
- race shocks are highly repeatable, to within a couple of pounds
- race shocks are easily serviced, so you can revalve them in a few minutes
- race shock adjusters work, and the adjustements are predictable and repeatable (this is the single biggest reason why Penskes are so expensive. Penske adjusters work as advertised)
- race shocks may be made of lighter materials
- race shocks may be more fragile; they may trade seal friction for durability (the assumption is that the shocks will be regularly rebuilt)
- race shocks can be valved to produce whatever curve you want.

When I'm setting up race shocks, there's a particular force curve (that is different for every vehicle) that I want to see - and I'll keep revalving it (or fiddling with the knobs) until I get the curve I want within a couple of percent.

Konis don't quite meet the "race shock" grade. They're not real repeatable (buy 10 shocks and they'll all be a little bit different on the dyno) The adjusters sometimes do funny things - they tend to be nonlinear (for a start) and I've seen other oddities too. Sometimes there's crosstalk on the adjusters. Adjuster settings DO NOT match shock to shock (ie, "1 turn off full hard" is NEVER the same on two supposedly identical shocks)

If the car is a full time race car, Konis CAN work for you, but you'll spend as much time fighting the shock as you will on developing the car - especially as it has to go back to Koni every time you want it revalved. Progress just isn't as quick as it is with a real race shock.

But if the car is primarily a street car, Konis are way, WAY better than all the alternatives. Street durability is good. The adjusters aren't perfect, but they're WAY better than some of the alternatives. Doing coilovers with real springs is easy, and that gets you both easy height adjustment and easy spring rate adjustment. And assuming that you've got the shock adjusted correctly, the actual performance of the shock is pretty good. The hysterisis isn't bad at all. And Koni likes to put a little intial "nose" into the shock between 0 and 0.8 in/sec so you can feel that you got something for your money.

But I can count on one hand the people who *need* something better. Me. Charles Moss. Fedja (well, maybe Fedja's car owner ) Maybe Trevor. Marc Berte. John Shepard. Marco Passente (I think there's some real performance to be had from shocks if you're in the 9 second club) Whoever bought the old Archer car.

Some of the people on this forum show promise, and may some day be ready to step up from a Koni... but that's for the future. For the majority, Konis are awesome, once the upper spring mount situation is sorted out properly. Guess what I'm hard at work on?

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Think of it this way - if shocks were engine management, Konis would be a SuperAFC - not perfect, but workable for most people. Bilsteins would be a Motec. And Penskes are a Magneti Martinelli.

DG

*** post edited by admin for Vendor policy reasons ***