Norm Peterson

I'm probably picky enough to custom-drill my LCA relo bracket adjustment holes 1/8" higher than I would otherwise, but I wouldn't ever quibble about 0.9" not being "about an inch".

Rear ride height with the fuel tank at various levels will vary by more than 0.1"


Norm

F1Fan

Hi Norm,

Yes you are!

Cheers/Chip

Danno-23

Not gonna argue and bicker on the previous posts commenting to me, the stick axles and so on.
Just looking for advise.
Ordering H&R Race springs, Koni Sport dampers, Eibach f&r adjustable swaybar, adjustable panhard, and some sort of camber plates for the front.
Does this seem like a reasonable setup? Or is one component lacking against the others?
Is there something else to this setup that is essential that I am missing? Ie; rear trailing arms.

F1Fan

O.K. with me. I just prefer that people not talk out of their butts. If you can do that I can help you build a much better S197 Mustang chassis. Here is some feedback for you on your selections.

If you want to put together a much improved handling suspension than stock for a street car this is what I currently suggest to you.

H&R "Race springs" are for posers. H&R Race springs are too soft and too low, they bottom out front and rear but where it is a more serious problem causing handling problems and potential snap oversteer. You will also have huge bumpsteer issues in front. This is a bad spring design for a street driven car and a joke for use on a track car. Pure marketing B.S.

If you want an effective sport spring Steeda Competition springs are the stiffest on the market for stock type non-coilover struts. Even so Steeda Comps at 225lb/in are fairly soft spring rate for a 3,500lb. with a 52%-53% front axle weight bias. Steeda's Comp springs do not lower the car much at all and this is because the suspension geometry is very good handling and they did not want to wreck it by lowering the car too much.

I'm on 350lb/in springs on my S197 GT and this is not too high. I run 400/lb/in spring on my DD E36 M3 which has a 50/50 weight balance and is over 300lbs lighter. Most serious E36 M3 street cars on coilovers are running 500lb/in in front and 600lb/in at the back. Granted this sounds high at the rear but the wheel rate is closer to a 300lb/in spring on an S197 GT due to the motion ratio of the M3's IRS suspension.

Konis Sports are a great choice for dampers. For the money you need to consider converting your stock struts to a coilover style strut. Ground Control offers kits that would work well for you for only a small additional cost over just using a factory style strut. This setup gives you the very good Koni Sport damper cartridge in a modified factory strut with the addition of a sleeve that lets you choose any spring rate you want and be able to adjust your ride height and corner weight the chassis. The difference is huge for only a small amount of extra cash.

Steeda makes a good quiet street camber plate but the Ground Control street camber plates are better. The GC camber plates are quiet and give you more camber adjustment range AND you can add some more caster which is very good for the S197's rather upright struts.

The Eibach anti-roll bars are solid if not optimum. If you use Steeda's Competition front bar with the standard diameter Steeda rear bar with solid links you get a very good setup on an S197 with a square wheel and tire setup. Not cheap but the difference is also very big.

I also suggest installing Steeda Competition upper third link with street bushings in combination with GT500 LCAs. The UCA is a PITA to install but it solves the most serious problems of the 3-link. Add the Steeda adjustable Panhard bar and Panhard bar brace and you are good to go until you learn to drive better.

Get it aligned. You want to run -1.75 to -2.0 degrees negative with zero to 0.10' total loaded toe-in. At this point you will need much stickier tires to really take full advantage of this suspension.

HTH!

Danno-23

Thanks for the info.

At the first of this thread, it is posted that the H&R Race springs are 300Front and 275 Rear springs though. Is this not true?

The Steeda competition springs have me a little uneasy, as I have read posts saying their front ride height actually increased over stock.

I don't quite understand your Eibach Swaybar comment - Solid if not ultimate? This means they are good, right? They seem to offer the same diameters as the Steeda bars, both with adjustability. Originally was looking at the Hotchkiss, but Strano says it's overkill, so the next closest with f&r adjust was the eibach.

So I'll look further into the ground control setup, but it seems their website is tricky to sort by application

Danno-23

So its $1599 for the Ground Control set up including Koni Sports, camber plates, and coilover springs. Decent pricing. Considering generally - The dampers are 770, springs 250, and plates 300. Its really only a few hundred more with the option of adjusting ride height and coil spring swapability. Looks like this is the way to go.

But I still need to know the deal with the H&R Race spring set

F1Fan

No, the H&R race are variable rate springs and unless you measure them on a spring machine with the same weight as an actual S197GT strut would press on the spring you cannot actually see what the spring rate is at actual working spring height. That number is inaccurate for this comparison. The real problem is that the spring rate is too low for the amount of drop which causes the suspension to ride the bumpstops all the time and messes up the suspension geometry.

This is sort of true. I had a set on my car before I went to Steeda's coilover setup and using the Steeda HD strut mounts the car did not drop the 1" Steeda claimed. But the good thing is that the suspension geometry was not messed up and the car had plenty of compression travel so the car rode better than stock with the Steeda tuned adjustable Tokico struts. The reason I had to go to coilovers was that even with the highest spring rate on the market the springs were too soft for serious performance use.

As I recall the Steeda Competition bar is 7% stiffer than the Eibach 35mm bar. Also the Eibach bars are not as well made. If you could see them side by side as I have you would not be willing to pay the extra money for the Eibach bars. Spend that money on a G-Trac brace or anti-roll bar brace to stiffen the chassis.

If in doubt just call and talk to GC. They are more than willing to explain their products.

F1Fan

It is hard to beat the GC kit's value. The big advantage nobody talks about on a well designed coilover strut is that you get a shorter strut body and strut rod. This gives you better ride because the reduced ride height most folks try to use causes a loss of bump travel. This loss can be compensated for by using a shorter strut tube body to get that bump travel back! The advantages of a coilover suspension is not just about ride height and corner balancing. If well designed for the vehicle a coilover system can also provide much better ride and spring rate choices. This is what make a well designed coilover suspension worth the little bit of extra money over the stock type and stock length coilover struts.

See my previous post.

Norm Peterson

If you lower the car, you may want to address the rear suspension directly. The rate of axle steer changes, and changes for the worse for cornering maneuvers as you lower the car but do not correct the geometry (the car will get slightly more straight line stable but more understeerish). Lowered too much (geometry uncorrected) and you can expect slalom performance to deteriorate. 1.5" lowering without geometry correction is probably too much for what I think your usage includes.

Like Chip said, the upper link is a PITA to do. If you're experiencing wheelhop out of the start, sometimes doing just the lower trailing arms (more commonly known as "lower control arms" or simply "LCAs" here in the States ) is sufficient. But you then need to match the LCA to your use, as they aren't all equally applicable to the various forms of motorsport. I will assume that it's either class-legal or you aren't worried about such matters.

You'd probably want something with a spherical joint at one end and polyurethane-bushed at the other. But it doesn't stop there. For a car that sees street use, you'll want the sphericals to be something other than the all-metal rod ends/Heim joints (think Johnny joints, Roto-joints, or Del-spheres). And there's clear benefit to be had by DIY-modifying the poly bushings as well. You'll want to keep them lubricated, because there can be enough stiction developed between "dry" poly and metal to feel as harshness and easily enough to make the tail too sensitive to throttle on corner exit. Never mind how I might know this.

From your other thread ( LINKY ), I gather that your autoslalom is essentially the same as autocross ("Solo" in SCCA-speak). For that activity, which is very heavily transient-intensive, the dampers are relatively much more important than in, say, hard street driving. You can take a lot of good information away from what the guys playing under the SCCA solo rule limits are doing, though it's best used in conjunction with knowing what they aren't being allowed to do. This varies widely depending on the specific class, of which there are several that the S197 Mustang can play in.


You won't be able to drive the Mustang quite the same way as you do the Contour. Throttle modulation out near the tires' limits is far more important than with more modestly powered FWD where it doesn't much matter from a stability point of view whether you gently get the inside front tire to spin just a little or hammer it loose by stomping on the throttle. Although it's been a while now, I did have a few years autocross experience in the 626 listed in my sig and I haven't forgotten everything about that experience (yet).



As to this . . .
comparing the Mustang's rear suspension to an oxcart in your third post on this forum probably wasn't the most diplomatic way to get started. Might have been another case of Canadian English and American English not quite lining up.


Yeah, with full social security age being less than a year away some people might call me 'old'. It is what it is, I guess, but that doesn't mean I think, act, or drive like the stereotype you probably have in mind. Even if the occasional bluntly-worded message board reply might fit the 'type.


Norm

F1Fan

I'm sorry I think I got my panties bunched up. This caused me to realize that I violated one of my first rules. How do you plan to use this car?

Is it a daily driver that sees very limited track time for HPDE or casual "fun" lapping sessions? A DD car that sees the track every weekend? Dedicated track toy? Does this car have to meet some sort of competition rule for parking lots or road courses?

I commented in general about the S197's suspension and some options without considering this info or what if any budget you have. If you have moderately deep pockets say $5K to $6KUSD and do most of the mechanical work yourself you can build a tremendous street car suspension with mostly off the shelf parts and an understanding of suspension ideas. Granted you will really need to add properly chosen wheels and sticky tires to really take advantage of this suspension setup. If you have access to a good local machine shop and a good alignment shop you can build an amazing car with some measurements and some effort on your part to work out the details.

The most basic grip & handling issues that can be reasonably addressed with the S197 chassis or most street cars usually include dampers, tires, brakes and handling/grip. The ability to tune a chassis is largely determined by budget and how far you are willing to compromise your DD (if it is a DD) for improved road course and/or parking lot performance and the rules if any that apply to your particular use. It also helps to have a second driver or a friend once in a while so you can leave the project car in the air to sort things out or wait for parts or work to be performed.

So being realistic what do you plan to do with the car, how much do you have to blow on suspension, brakes, wheels and tires? Do you drive it in the winter? Also consider that highly modified suspensions need much more regular maintenance to keep your investment working safely and at its best so budget for this too.

HTH!