2008 Springs Steeda, Eibach, H&R or ?

Eibach Sportlines

thought a different angle might help.

No problem on the photos ...just "paying it forward" for the info I have received from this site.

Do not use that GC complete kit... You'd be better off with the standard Koni's and the conversion. The valving in a standard Koni can handle quite a lot of rate, and frankly there is no need to be messing with revalving them. They don't need shortened either.

Further, GC rear springs will come loose when the axle droops (not a particularly good thing). And notice how the spring rates aren't being talked about? They often include spring in kits that I don't use. In fact the last time I sold their stuff (I quit as their service sucks), I got into a battle about rates and they didn't want to give me what I wanted (and won National Championships on). Instead they wanted to force a 150 lighter front spring and a 25 stiffer rear on me because they felt it was better.

Here news. If you aren't going to be corner weighting the car, and nitpicking on spring rates like really on competition cars do, don't **** with coil-overs *unless* you just can't live without the ability to monkey with your ride height. And in that case, you have better options for coil-overs than that GC kit. Again you could run Koni's with the conversion, you could run Bilstein's, KW's, and any number of better combinations built by companies I trust way more then GC.

Please allow me to be a bit more blunt:

A car is designed to be a certain height. There is wiggle room, but the more and more you go away from the height, the more and more issues you run into. The Super Sports are a spring I can get. Remember that my standing in life is to make a car work as best it can. I feel too much lowering (and yes Virginia I feel 1.9" is too much) simply compromises the suspension on roads that are not smooth as glass, and most public roads are not. Further, the lower the spring the firmer it has to be, assuming it's done right) to keep the car from slamming onto the bumpstop @ 400 mph... What a solid axle car doesn't need for ride or handling is to be made more into a empty 3/4+ pickup (lots of spring, solid axle...).

Looks and geometry and a working suspension are often at odds. I find it best to stay with a more moderate 1.2-1.5" drop whenever possible. Running coil-overs might allow you the look you want, but does not change the geometry issues associated with lowering too much. And the other issue with coil-overs is this: They are sold either with really high rates to account for the fact you can slam the car, or they are sold with reasonable rates for a moderate drop, but then folks slam them anyway.

And in the end, let's look at this practically. Nit-picking over 1/4" isn't often anything that can been seen. A lowered S197 is obvious to anyone. There is not a magic cut-off @ say 1.5". Think about that for a second. Nobody can tell me that a 1.2" lowering isn't noticeable, but a 1.5" is. Grab a ruler, look at really what 1/4" (as an example) is.... then imagine that difference from say 20 feet away.

My preferences run toward the GT500 springs on a GT/Bullitt car because I prefer the more level look vs. lowering but still having a bit of tail up look left. I also prefer the less drop for geometry issues like roll center height and camber gain issues in front of the car. And I prefer the little bit firmer spring rate that GT500 springs have. Most companies make both GT and GT500 springs. Vogtland (my preference), Eibach and H&R are all examples of major players that do this. If you want normal springs, or you prefer the more equal drop, that's fine too. Looks matter, and I don't mean to belittle that. But in the end I'd rather nitpick performance than looks.

Understood Sam.... it all depends on where you come from. As an autocross specialist, it makes sense you would prefer to have as much suspension as you are capable of dealing with. Others like me, may not be able to fully utilize a car like you, and can be perfectly happy with another compromise.

I'm an Industrial Designer, so looks matter as much to me as performance. And I'm willing to give up a tiny bit of the suspension performance to make the car look MUCH better.

It also doesn't help that springs RARELY, if EVER, lower the car the advertised amount front AND rear. Usually the discrepancies are enough to dramatically change how the car looks. 1/4" can be the world to a designer!

Atleast changing out springs is relatively easy. If you don't like the first go round, you can always change it.

I think I'm going to try the H&R Super Sports, every 05+ Mustang I've seen with them looks great! And I haven't heard a single bad thing about their ride either.

Now being as you don't recommend it, can you sell it? Or will your conscience get the best of you???

Koni Sports for the S197 are single adjustable on the *rebound* damping. Not the compression, and not a linked adjustment on both sides.

There are Koni Double Adjustables for various cars like the Fox and SN95 cars. DA's offer independent adjustment of compression and rebound. I also think they are overkill for most everyone, and in fact I run singles on my cars (and own some DA's for that matter).

And you are right on about D-specs. They are technically what's called "double acting, single adjustable". They have one adjustment, but the compression and rebound damping are linked to each other. You can't get a change in one without a change in the other.

I've had and used D-specs and Koni's both on these cars (more than one in fact). I made the change to Koni from D-spec and don't regret it for a moment. D-spec work ok, but are a lot more fragile. There are various threads on other forums about their problems. And their warrant support is beyond terrible. Koni's are built better, and much better supported on the warranty side, should you need it. But they also work better. You get better rebound control without the associated increase in often unnecessary compression dmaping which only serves to make the ride more brittle.

Does that answer your question?

BTW, I see you are in Pittsburgh. Because you are close, I'll make you the same offer I make others. Come on up to Brookville (80 mi. NE of Pittsburgh) and take a ride in my GT on Koni's if you want to feel them in action. My personal GT is stock on the suspension otherwise, so folks know they are feeling the dampers and not some other part. Eventually I might change the car to run it more for autox instead of the others cars, and so that might not always be the case. But for now, anyone can see exactly what the Koni's bring to the table.

Koni's

Thanks Sam, I’m quite familiar with true double adjustable shocks and what there advantages are on the race track. They are probably not necessary on a street car, and my Bullitt is a street car. The only advantage that I see on a street car is that you can dial in the compression and rebound that you like without changing out shocks or revalving them so that they match up with the springs along with fine tuning the chassis. Since I was thinking of making a spring change this would help. I thought pay once and get all the adjustments possible and maybe this would be the cheaper way to go. I’ll continue to have to think about this. It seems to me that the only difference in the Bullitt chassis over a standard GT is the shocks with more compression and rebound. That’s just a seat of the pants determination.

If I get a chance I may come up and see your car, and would also be interested riding in one with a spring change. I already have too many money pits (that’s what I’m told) and have to make the best decision . Thanks again Sam

Jon said:

Thanks Sam, I’m quite familiar with true double adjustable shocks and what there advantages are on the race track. They are probably not necessary on a street car, and my Bullitt is a street car. The only advantage that I see on a street car is that you can dial in the compression and rebound that you like without changing out shocks or revalving them so that they match up with the springs along with fine tuning the chassis. Since I was thinking of making a spring change this would help. I thought pay once and get all the adjustments possible and maybe this would be the cheaper way to go. I’ll continue to have to think about this. It seems to me that the only difference in the Bullitt chassis over a standard GT is the shocks with more compression and rebound. That’s just a seat of the pants determination.

If I get a chance I may come up and see your car, and would also be interested riding in one with a spring change. I already have too many money pits (that’s what I’m told) and have to make the best decision . Thanks again Sam

Click to expand...

Well if you time it right next year it's possible I could have both my car and the Shelby GT I autox here at the same time. Both on Koni's, but of course the SGT is on the Eibach springs it comes with (being an F-stock autox car, I can't change them even though I think there are better springs).

As for DA's, I have to be honest, I don't think they are necessary for even most track cars. I firmly believe the compression damping just needs to be right. And because the stock wheels and tires are so heavy, any equal or lighter combination effectively adds compression damping vs. the unsprung weight anyway. Remember I have DA's for my Camaro, and don't use them. I've dealt with DA's on older Mustangs a lot, and never ended up using more than the base compression damping in those either. Koni's are rebuildable so you could have the converted if you really, really wanted to.... but the cost is pretty high.

Now, that said there are also a few true split DA's out there. KW is a prime example with their Variant 3 Coil-overs (and that takes care of the springs too). But that might be a bit more than you need or want. AST from Holland has some S197 Mustang stuff on the way, and they'll have the option on not only split, but remote reservoir DA's (and even triples). Of course Eibach has their kits as well that have remotes. One uses a double acting single adjustment, the other is a split adjustment.

I have access to every one of the things mentioned above (as well as Tokico, Bilstein, Edelbrock too). Hell, I could have Koni build a set of 28 series race shocks if you wanted.

Given all that, I really think the Koni SA's are by far the best bang for the buck there is.

A spring change doens't effect the compression damping, that's a control of unsprung weight (and unsprung weight is just that, not sprung weight). And on the rebound side, the Koni's have a big range of adjustment. While it varies, generally you have about 100% more force @ full firm than full soft. I've never had to revalve a Koni for my needs, and even on the Eibach's on the SGT, I run the fronts about 1/2 way up, and the rears only about 1/4 of the way to full firm and that's with about 60% stiffer springs that are also shorter. Suffice to say you have to get pretty nuts on spring rate to need more than Koni's can damp.

Have I mentioned I like this site? Might be the best S197 group I've found in terms of discussion....

Probably the best answer I can give you is that I have Koni's on my Mustang that is not a primary (or for that matter a secondary) autocross car. I've put 15k mile on my car, and it didn't take me but about 1k to change the stock shocks to the Koni's.

I'm not saying there aren't other options, there are. But for the quality of the product, the range of adjustment, and the fact they tend to improve impact harshness (vs. staying the same or getting worse), yes I think they are a great choice for a street car, *IF* the person gives a rat's behind about how the car drives.

And I'm with you on the SGT thing. The stock dampers are rough and we have made each of those we've worked on not only handle better, but more to the point of your statement also ride way, way better than the FR3's Multimatic tuned dampers. That's been a universal finding from everyone who's had both. I don't mean to digress in to Shelby GT stuff, being this is a Bullitt Forum. But it's pertinent information given any Bullitt on lowering springs is essentially the same thing.

The Koni's, while not cheap, are IMO the best bang for the bucks. The thing with that statement is that is tends to make people think about pricing only, and they tend to overlook the value of the product they are getting for the price. That's where the Koni's excel over say D-specs which while cheaper, aren't as durable, and don't offer the same combination of effective damping without as brittle ride quality. And that's not even getting into the fact Tokico warranty sucks (which matters as it's needed far too often).

Sam, you really are a wealth of knowledge in this area, as is evidenced above, but can you please give a simple recommendation for my simple mind to grasp?

Generally, I am happy with the ride and handling characteristics of the car. The problem comes up when I start to push it, especially from a set of lights and around wide sweepers. Our pavement up here is not the greatest; many cracks, frost heaves, potholes, missing chunks, which often causes wheel hop and unsettled rear.

I would really like to find the best option to keep that rear planted, and not sure what the first step should be. I have been thinking springs to lower the car moderately ~ 1" and a set of upgraded shocks.

The car is a weekend cruiser and I have no plans to track it (at this time... I might possibly go play at the local drags or auto-x in the future, but just to play around, nothing serious what so ever.), and want to be able to do a 1000+ km road trip without having to wear a kidney belt. So ride quality is very important, but really want to improve handling. Also, I don't really want to have to be constantly playing with/maintaining the suspension every few thousand miles...

From your above comments, sounds like Eibachs and Konis would be a good choice, or is there a different combination you would recommend?