Suspension Voodoo

[Greg Amy]

Sorry for the quote/response format. I hate it, too, but it's the easiest to attack.

"any suspension can be made to work well once you stop it from moving." Most appropriate as relates to struts...

A damper only works when it's moving. If you are sprung as stiff as a go-kart then dampers really don't matter that much.

Not necessarily true. If you disagree, consider the ramifications of using 1100-in/lb springs and no dampers...unless the suspension is truly solid, there is movement that must be controlled via dampers.

..first, a strut car can be make as fast as an "a" arm car.

Only if you can move the pickup points of the suspension components. In Improved Touring we cannot do that. Ergo, by the design of a street-geometry MacStrut car, it will never be able to be as fast as a comparable street-geometry a-arm car.

Second, front drive cars like a lot more spring than a rear wheel drive...something esoteric about keeping the inside front wheel planted.

Well, no. It's something more esoteric about most of them using MacStruts and that that implies.

Third, shocks, shocks, shocks...talk with Lee at Koni...

Si, si, si!

I...purchased a set of 8600 series Double adjustable shocks put together by Koni USA.

Off-the-shelf valving? Those are good for ~500-700 in-lb springs; after that you'll need to revalve them for more rebound.

I have 500 6" Eibachs in the front and 400 7" Eibachs in the back.

Start by swapping the spring rates front-to-rear, and start looking for springs in 50-lb increments up to 700.

The set up will most absolutely be different on Hoosiers than the others.

You're tire-limited, now. You'll never be as fast as the others until you buy Hoosier or comparable.

Greg, at that point in time I was more than willing to pull the trigger on the "better" suspension package.

I know that, Dave, I'm just pulling your nuts.

And, your experience is not relevant, as you followed Greg's Step #1...

Someone else noted (was it in this thread?) about how rates and all that are irrelevant once a tire is in the air. It may work that way in computer simulations and in the book of theory, but in the Book of Reality it most decisively remains important. There are many other factors to consider, such as swaybars (which impart the lifted wheel's suspension forces to the other side) chassis flex (which imparts forces through suspension components), and wheel stiffness.

And in the end, never settle for "what the experts say" because your situation is always different. I can't count the number of times we've made things work that "the experts" say are wrong ("Kakashi, dude" is one of our favorite team sayings... http://www.kakashiracing.com/team.html)

Lots to consider, lots to test.

GA