lqdslvr

Wow, F1Fan! That's precisely the information I was looking for and a world of help. Based on what you have said, I'm going to break this down into steps and deal with first things first. My first step will be Steeda Comp springs and the Tokico D-Specs, along with an adjustable PH Bar and Brace. I'm also going to copy this thread to my computer (just book marking it is not enough to safeguard it for future use!). Thanks again for all the help!

lrgnation

here ya guys go

http://www.griggsracing.com/index.php/cPath/10_1025

F1Fan

Hi Irgnation,

The Griggs GR suspensionsare nothing new, the applicationof his basic GR race suspension onthe S197 chassis is. While I agree with most of what Griggs finds wrong with the S197 chassis for a race car mostly I don't want to spend an extra $10K over what I've already spent on my entire suspension for a daily driven street car.I also don't want the horrible extra high levels of road noise and vibration of a solid bushed suspension. Griggs has done what most of the parts I have suggested do but from a racing perspective with less care for important daily driver stuff for like noise, vibration, cost and ride.

Cheers!

F1Fan

Hi qdslvr,

I did get a little windy thougheh? Just a bit of a breeze here with some hardware to go with thegeneral suspension plan. All of these parts are for a high performance street car with a road course focus hence all bushings are intended to be polyurethane where possible.

Something I did not mentions is the huge roleproper alignment plays in the feel and handling of a car and how well a car tracks, brakes,turns in, exits and acellerates out ofa turn. Do NOT underestimate the power of a good and knowledgable alignment technician with tools in good repair. Once you find a good one keep him happy and buy the shopa case of their favorite beerasa tip for a good job. Keep them on youChristmas list.

improvecontrol of body and suspension (body motion andtire contact patch with track surface)
Adjustable struts and rear dampers are a must, the non adjustable dampers cannotmatchthe differentsport springs available so adjustability is required for good performance and ride.I like the Tokio D-Spec kit but the Koni Sports will also be great once they ship but the Koni sportscannotbe as soft riding due to the lack of adjustment for compression damping. There are obviously other adjustable damper options available but they are all going to be racing oriented and require more work to make work well and then there is the cost of maintainence and regular rebuilds that a street oriented performance damper does not have to deal with.
improve spring rates for use or application (center of gravity,chassis handlingbalance, brake dive)
For springs I really like the Eibach Pro-Kit springs I used to have on my car for the look they give the car. While Eibach Pro-Kit spring rates are excellent thedrop is really too much for a street car and marginal even on the race track due to limited rear axle travel and excessive bottoming.With this much drop in ride height the suspension geometry changes require correction for a good handling chassis. Steeda's Sport springprobably has the best compromise between ride height, suspension travel andspring rates for a daily driver street car. But for a performancespring the Steeda Competition spring rates are the way to go IMO as they have a slightly higher effectivespring rate comparedto the Eibach Pro-Kit springsand slightly higher ride height. I also prefer Steeda's linear rate spring because it is easier to findgood damper settings for than a progressive spring like Eibach's Pro-Kit.
correctlateral rear axle centering and location (minmize roll center changes)
Ideally a Panhard barwouldbe stiff, light and adjustable with hard poly bushings or you might just as well keep the O.E. PB. To help the chassis live with the increased shock and lateral loads of a stiffer PB and firm bushing mounts along with helping the chassis transmist rear axle feedback to the driver you need a stiff light brace to help keep the Panhard bar located in the correct place. I like Steeda's adjustable Panhard bar and the matching Heavy Duty PB bar brace. BMR's Panhar bar and support brace are good but are alsoheavier and not as stiff due to being made from mild steel DOM tubing. If you have the choice chrome-molly alloy steel tubing is a superior material in these applications. Why settle for less than the best material and save weight at the same time? O.K. so it can cost a bit more for higher quality parts butlike they say "you can't take it with you."
improve front control arm location
Improving control arm location is important because it affects steering,steering feel and alignment. All of these things are what helps the driver drive the car to it's limits of grip. For this task I suggest the G-Trac bar which basically ties the front control arms together to improve location. I also suggest the inexpensive Steeda bushing insert kit which also increases contol arm location by constraining the fluid bushing preventing the control arm from movingout of alignment. Steeda supplies two different durometer bushings and I suggest the hard black bushing inserts for the best steering response andfeel. You can also replace the front control arms with GT500 arms for the stiffer bushings and stronger ball joints.
correctbumpsteer error
Bumpsteer causes the car to deviate from the driver's intended path by altering the steering input to the wheels when one or bothof the frontwheels is deflected. Bumpsteer is bad and can make the drivers job very difficult to manage when cornering or even trying to steer in a straight line. The fix is not too expensive and is not hard to achive even wthout a bumpsteer gauge. Just follow the installation directions and you will be amazingly close. I removed the springs and measured throughout the fullrange of suspension travel. Then carefully check within the range most likely to be used on the road. I give the most weight to the range used on theroad and track if a compromise has to be made. I used a Steeda bumpsteer kit but there are others that are similar from Baer, Eibach etc.
improve longitudinal rear axle location (minimize accelleration/brake wheel hop)
Thecontrol arm that has the most impacton improvingrear axle locationto reducing wheel hop is the UCA. The UCAhas the highest load, isthe weakest of the control arms, has a potentially weakmount, hasthe lowest mechanical advantage overaxle movementsand the fewest and lowestdurometer bushings. The LCA's certainly play a part in wheel hop also but their part is much smaller because there are twice as manyLCA's with twice as many bushings and the mounting points have much more leverage overaxle movements. This is why the first of the 3-link suspension control arms to be upgraded needs to be the UCA and the UCA's mounting point. If you can improve the geometryand reduce pinion angle changes throughout the axle's travelwhy not take advantage ofa better designed part if you are going to be under the car messing with it anyway?

[color=#000099][i]Steeda's new adjustable Comp/Street UCA kit with heavy duty adjustable UCA mount is a fine design that killsfour birds with one stone. First the Steeda UCA improves location with a three piece dual durometer poly bushing design. Second the Steeda UCA improves instant center on a lowered S197 chassis with LCA relocation brackets in the correctpositionby using the new UCA mount's additionalmounting position. Third the UCA's longer rod length combined with the repositioned mounting point onSteeda's heavy duty mount improves geometryand reduces pinion angle changes duringaxle movements. Fourth the new U

jmsurpri

Great writeup. Thanks for taking the time to explain in detail. I have Steeda LCAs with poly bushings. Is there an option for me to just buy rubber bushings for these?

F1Fan

Hi Jim,

You would be better off going to the GT500 LCA's sold by FRPP for $100 a pair. AFAIK there are nooff the shelf rubber bushings for the Steeda LCA's as they were designed to use stock Steeda supplied polyurethane bushings, steelinserts and shells. But you can call Gus at Steeda and ask him if they can make up a set or if there is something that could be adapted to fit your SteedaLCA's. The GT500 LCA's are reinforcedheavy duty stampings and are designed with much stiffer OEM style rubber bushings to improve axle control and dampen road noise and vibration. I doubt that they will improve your cars actual ride motions though they will most likely be a bit quieter and let in less road and tirenoise.

I know youhave a percieved ride quality issue with your S197GT and was wondering if you have driven a stock S197 Mustang GT to see if your ride expectations are achievable. If you drive anew stockS197 Mustang GT and you think it is too hard riding youare wasting your time trying to find a way tomake the car ride better you justcan't do it on this chassis and retain good performance once past the middle of the curve.

Thebest riding struts and rear dampers you can buy for your S197 chassisareBilstein HD dampers.Bilstein HD dampersare designed to bethe highest quality O.E. type replacement damperout there andcan improvethe stock S197GT's ride significantly even on moderately sporty springs.Bilstein HD's are generally the the bestdampers you can by for sporty performancewith a high level of comfort but are lacking in performance at themiddle and upper end of the handling performance spectrum. Bilstein dampers use extra large diameter pistonsdue to the single tube design which has always given them a significant edge in sensitivity to small movement damping control. Probably late next year Koni is supposed to release thenew Koni FSD line damper for the S197 chassis and it may ride better than the currently available Bilstein HD dampers but I wouldn't bet on it.

I hope this helps!

jmsurpri

Thanks for the response. Yes I am on a quest to smooth out my ride. No I haven't drivena stock GT yet, but have been thinking about going to a dealer for a 'test drive'. I don't have any problems with road noise or vibration, it seems quiet enough and I don't think I feel any vibrations. The main problems I have are having any size bump or dip in the road transferring right to my body. In other words, I physically move up and down in my seat no matter how big the imperfection in the road. Hard to describe. If I can smooth that out, I will be a happy camper. That to me sounds like bushing material after reading your posts and others. all the hard bushings in LCAs and sways not cushioning the little (and big) suspension hits.

F1Fan

Hi jmsurpri,

The issue you are having is spring and damper related. I really think you need to test drive a stock GT to see where your problem is. OBTW, whatwheels and tires did you buy to replace the 20" setup you had previously? Can you tell us the brand, model and size of the 18" tires? Tires make a huge difference in ride also just as air pressure does.

Cheers!

jmsurpri

I have Tokicos but have had a hard time trying to find a good setting. I'm currently at 5.5 turns out all the way around and it's OK.

I bought the deep dish bullitts from American Muscle 18x9, and have the Nittos mounted 255x45zr18 all set to 35psi.

rnail

Thanks for all of the great feedback and discussion on this. 2 questions.

F1Fan,
1) I see you really like the Steeda Sports. I have read others who like the Steeda Ultralights (Crazy Al). I am having a hard time deciding. Any opinions on this? I would go with the Sports if I could be assured my ride would not be Jittery. What I'm looking for is firm, but refined flat handling. I don't mind feeling a few hard bumps as long as they are well controlled and theride is planted and stable between them.

2) Also,last month'sMuscle Mustangs and Fast Fords had an article where they reviewed the Steeda Q335. That suspension consists of the Steeda sports, their ProAction shocks, theirfront and rear sway bars, G-trac brace. The reviewers were making comparison to their earlier drive with the FRPP outfitted GT-H. They mentioned that the Steeda kit did not suffer from the understear that plagued the FRPP kit and that the Steeda performed much better at the trackbecause the Steeda kit hadneutral handling -this with front and rear sway bars. Is their adjustable front set up such that they can achieve the neutral handling with their kit?
Thanks,
rnail