Suspension setup advice

SoundGuyDave

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Okay, I'll throw my hat in the ring here, and just bring hard tech, not supposition...

1) Spring rates matched to the application (race, track toy, street) and good dampers able to properly control them make an incredible impact on the controlablility and consistency of a car.
2) The S197 chassis does inherently understeer a touch. Not horribly, but noticeably when pushed to the limit. The thee leading causes are (flame suit on) Excessive entry speed, abrupt turn-in technique, excessive nose weight. There are a lot of different things you can do (without touching a toolbox) to ameliorate or minimize the push, but it's just inherent to a 3400+lb vehicle with a relatively high CG trying to change vectors.
3) "Coilover" to me simply indicates a particular spring/damper arrangement with an adjustable spring perch location. Period. The word itself does not denote a magic bullet for suspension or handling woes. GMitch does provide a list of positives to the arrangement (corner-weighting, ride height, low spring cost), but just "getting coilovers" will not suddenly transform a nose-heavy 4000lb supercharged S197 into a GT3RS killer.
4) The Koni Yellow/Steeda Sport/MM plate setup is a proven combination of parts that I wouldn't hesitate to recommend to a track-day guy, or even an infrequent visitor to the road course. In short, they just don't suck. If you're hard-core, then yes, there are other proven setups that make more sense.
5) The Eibach R3 may well be the best thing since sliced bread, but I will wager that a quality damper (all other things being the same) with no adjustments at all will be "better" than a mis-adjusted high-end damper. To me, if the compression curve matches the springs, and I can adjust the rebound over a wide range (no digressive curve discussions, please!) to suit differening tracks and track conditions, that's more than enough for 99% of the people out there, including me.

If anybody needs to ask, I have owned or driven (on track) quite a number of differing suspension setups on the S197 chassis. Stock, lightly modified, Koni/Steeda/MM, AST singles, KW Clubsports, and even SLA/Watts cars. I've instructed in an even larger variety.

If you want to see what good springs and dampers can do, simply look below:



Now, if you want to cure the "push" in our cars, you need to go back to basics, and make sure that the driver mods are up to snuff. Lower your entry speed a touch, smooth out the control inputs, and STOP going too fast through the slow corners, and too slow through the fast corners. They should all "feel" the same (plus or minus aero aids). A tick tight on entry, neutral through, and then a tick loose on exit. For the slow corners, trailbrake a touch to get the rear rotating at entry, and suddenly your push will all but vanish. Then, get on the gas early and HARD, at or before apex, and rocket out. Try to put just the outside rear tire on the rumble strips. That will give you just about the right slip angle to really get the tires working, AND will confirm that you're carrying appropriate speed through apex assuming you don't have throttle-induced oversteer. Until you, as the driver, can control the attitude of the car through all phases of the corner, tuning the suspension to fit your errors is just a crutch.
 

SoundGuyDave

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Chicago, actually... I'm at the usual tracks throughout the season, and Putnam is one of my favorites.
 

Nicu7

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Just this past spring Putnam added around 12 new garage areas and are starting on a new club house. Its great seeing them expand like they are. The owner is building his race cars year round there now. I guess his shop used to be based out of florida. They are pretty sweet looking. I've only seem them sitting in the garages and don't really know much about them.
 

Vorshlag-Fair

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It's all a compromise based on budget, and streetability vs trackability. Unless it's a separate budget, I'd buy the bare essentials, and spend the money on track time. Throwing a bunch of parts at the car won't make you a better driver. It'll make it easier to drive fast, but don't neglect seat time. The same can be said for safety gear.

Truth.


First things first....Dump those Sportlines and get something that won't lower the car beyond it's usable range, having you bottom out constantly. I don't care if you go back to stock, it'd be more usable than those stupid things. Coilovers are great if you are really going to use them and get the car properly corner balanced...see adjustable endlinks. Otherwise, H&R Race Springs are as stiff as you can easily get on there. Ground Control makes a cheaper option imbetween, but it's a compromise and I think you'll be better suited to just go coilover all the way or stick with the H&R Race springs and GOOD dampers.

Second, Dampers, or shocks and struts to you crazies. :) Get the best you can afford. They make the biggest difference especially when combined with proper spring rates. Koni yellows are going to be the favorite here. I don't care for the DSpecs. Bilstein makes quality dampers and coilovers, if you don't think you'll actually play with the adjustments, and just focus on driving, or if your class your running doesn't allow adjustables. Eibach has great marketing, but I've yet to see anyone actually racing on their R2's... seems like street bling to me until it becomes proven quality. Then there's the higher end dampers... Moton, AST, KW, FR500S from Ford Racing, Koni Racing series... Without knowing exactly where you're at, it's hard to say what you need... All I can tell you is buy the best dampers you can afford.

Agreed. There are a lot of cheap dampers out there, and a lot of Chinese junk, including one that says its Made in the USA and highly recommended by one poster in this thread. If it seems too cheap for the features to be non-Chinese, it probably isn't.

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A proper damper that uses coilover springs is probably shortened and should work better (have more usable stroke) at a lower ride height than an OEM replacement strut/shock combo. I am also a big fan of adjustable monotubes, which narrows your choices a good bit and ups the ante. The AST 4100 single adjsuatbles above served us very well and were only ~$2000. The Moton Club Sport double adjustables with remotes are a bit more serious and start at $5500, which is not really meant for the casual track day guy.


Third- Skip the sway bars and the bracing for now. With high rate springs, and quality dampers, you'll have plenty of roll control. Once you get some time under you, then decide if you want to make small changes with sway bars. Also, the car is plenty stiff for what you are doing. Bracing only really helps when you're eeking out .10 seconds on these cars.

Agreed again. So many people think that the bolt on bracket trinkets are magic. They are not. Proper dampers and spring rates, with a lowered ride height and usable suspension travel at that height outranks all of the bolt-on brace trinkets available.


Fourth- Tires, tires, tires. Once you feel comfortable destroying street tires on the track, you're ready to step it up... Dedicated Track wheels and tires. Tires allow you to go faster around the track than any other performance modification. Again, get the best you can afford.

I agree, tires are HUGE part of the equation. No other single mod can make as much improvement as tire. I would also add "bigger is better" when it comes to most cars, especially big heavy cars like S197s.

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I feel like 315mm tire at all four corners is the perfect size, if its a dedicated track wheel and tire set-up. With a centered axle (adjustable panhard rod or watts to fix that when lowered), lower CG, enough camber up front, these fit without even a hint of fender rolling.


This post I'm quoting in this thread is great advice - best one in the thread. This guy "gets it". :)
 

Sky Render

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I'm getting my alignment checked on Wednesday in preparation for the new season. The following is what I'm planning on setting it to. This car is autocrossed 3-4 times a month during the summer and is also driven near-daily.

Camber: -1.8, both sides
Toe: 0"
Caster: Factory settings

Although I liked the increased turn-in from additional caster, my car tramlines horribly right now. As in, the wheels is turned nearly an inch to the left when going straight and ruts in the road sometimes make it feel like the wheel is being wrenched out of my grip.

Thoughts?
 

sheizasosay

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-1.8 is what I'm driving on the street. I have been looking for crappy tire wear, but these damn Eagle GS-D3 tires are taking their time on wear.

When I had Falken Azenis 615's on my car, I had some tramlining. You just need to go drive the crap out of your car and burn that rubber off and get some new tires. I don't think there is anything else you can do about tramlining.
 

Sky Render

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-1.8 is what I'm driving on the street. I have been looking for crappy tire wear, but these damn Eagle GS-D3 tires are taking their time on wear.

When I had Falken Azenis 615's on my car, I had some tramlining. You just need to go drive the crap out of your car and burn that rubber off and get some new tires. I don't think there is anything else you can do about tramlining.

Wide tires cause additional tramlining, too, but my car is doing it on my street NT555s. Caster has a very large effect on it.

According to the instructions that came with the MM Caster/camber kit (which are kept in my glovebox to hand to alignment techs):

"It is typical... to set the passenger side caster to a slightly greater amount than the driver side setting. For street-driven cars, a difference of 1/4* to 1/2* will help counter the effect of road crown, and prevent the car from pulling towards the right on most roads."
 

Norm Peterson

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-1.8 is what I'm driving on the street. I have been looking for crappy tire wear, but these damn Eagle GS-D3 tires are taking their time on wear.
Right about the same here, and as far as I know the car has been at least at -1.7° ever since it left the assembly line over 5 years and ~30,000 miles ago. Tire wear has been almost dead-even on both sets of tires (the OE BFG 235/50-18's I use through the winter and the "3-season" set of 255/45-18 GY Asymmetrics).

At such a camber setting (that's substantially outside Ford's range), your driving does have to be enthusiastic enough often enough. Though I doubt that's a huge sacrifice for any of the regulars in this particular forum on this particular site.


Tramlining is mainly a tire construction issue, with some tire makes/models being much worse than others. Might be related to such things as "ply steer" and "conicity".


Norm
 

sheizasosay

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Tramlining is mainly a tire construction issue, with some tire makes/models being much worse than others. Might be related to such things as "ply steer" and "conicity".


Norm

Norm can I call you Papa Bear? That's an O'rielly thing. Word of the day.....do not be a "pettifogger" when writing the Factor.

Now you go look that word up while I try to figure out what the hell "ply steer" and "conicity" is.
 

Sky Render

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Tramlining is mainly a tire construction issue, with some tire makes/models being much worse than others. Might be related to such things as "ply steer" and "conicity".


Norm

Then would that explain why the tramlining has seemed to get slightly worse as my front tires wear down? My rear tires have less wear (they're almost new, actually). Do you think swapping them onto the fronts would improve things?

Note that I only care about solving this "problem" when I'm running my daily-driver street tires. I have a separate set of super-wide "race" tires that I run only driving to and from events.
 

Norm Peterson

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Norm can I call you Papa Bear? That's an O'rielly thing.
Sorry, "O'Reilly thing" doesn't mean anything here. Seems there's only about 4 of their stores in all of NJ.

I suppose I could have omitted mention of those other terms and left this thread without a possible trail to follow further.


I certainly would expect greater tread depth to add some little local compliances that could take some of the "sting" out of any tramlining.


Norm
 
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Sky Render

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Conicity is when the tire is cone-shaped due to the insides being worn less than the outsides (or vice-versa).

I'm going to rotate the tires back-to-front after the alignment and see if that helps.
 

Norm Peterson

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Or when it behaves like it was worn that way, even though it's got zero miles on it and isn't worn or shaved at all.


Norm
 
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Sky Render

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Hmm, just about everything I'm reading says tires cause tramlining much more than suspension setup. So I guess I should rotate those tires and find out what happens.
 

Sky Render

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My car still tramlines a bit after the alignment, probably due to the tires. But it seems to be much less.

The real issue was that I had toe-out on one side and toe-in on the other, which caused my car to go to the right when the wheel was straight. That was straightened out to zero toe.

I also upped the camber from -1.6 to -1.8.
 

sheizasosay

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My car still tramlines a bit after the alignment, probably due to the tires. But it seems to be much less.

The real issue was that I had toe-out on one side and toe-in on the other, which caused my car to go to the right when the wheel was straight. That was straightened out to zero toe.

I also upped the camber from -1.6 to -1.8.

Now just make sure you drive a "little" bit like an asshole on the street so you can get even tire wear ;)
 

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