Lift or Down Force ?

[SPARKY]

"IMO a little lift goes a long way, most time the wrong way."

I admit it , I am a coward about body lift ever since my 65 160 mph Olds road walked--bad-- with out a substanal rake. The reason I like solid suspension on LSR cars I want to minimize the chance of the angle of attack changing. It doesn't much matter which is the cause, the spoiler creating down force, or the front end lifting because of pressuer changes. Without good data, which I do not have,  I would rather put up with the problems of unsprung.

[Cajun Kid]

I too want to make sure I know what the car is doing on the big end...

On board data and wind tunnel data... seems to be the answer...

eye ball engineering and seat of the pants are only good up until the point that they aren't !!

Charles

[SPARKY]

spot on

[MAZDA1807]

You could run solid suspension until you want to run a production class. I believe the rulebook says "original running gear design" or something close to that.

[Stan Back]

But I'm not sure they check the "compliance" of the shock absorbers (nor do they want to).

Stan

[MAZDA1807]

But I'm not sure they check the "compliance" of the shock absorbers (nor do they want to).

Stan

In inspection at SW we made a car find some coilovers because he had A-arm suspension with solid struts in place of the shock/coilover.

[MAZDA1807]

I can only speak for myself in inspection, but we should be as throe as possible. I'm sure Dan has seen stuff thrown out of impound for less. It only takes the other guy(s) in your class to go snooping around to try and find some way to protest. Just saying.
Peter.

[Cajun Kid]

I prefer suspension, and my home track is Maxton, therfore suspension is a good thing.  I just has some fine tuning to do.. Since those pics are from the Stude's firts runs at Maxton (where I had the car set up as high off the ground as I could) in order to make certain my air dam or other parts of the car did not hit the track or the return road.   Now I can lower the front 1/2 to 3/4 inch which
will increase the rake and most probably reduce or eliminate the front lift.  It lay however increase the rear down force, so then I would have to decrease the rear ride height, or spolier lip angle or spolier lip surface lenght or some combination of those 3. 

Hmm,, looks like I better reserve an extra hour of wind tunnel time ?

Charles

[krusty]

Charles    1) You should have in your set up notes the distance from the bottom of the air dam to the ground (if not, bad boy, you need to know this and have other measurements recorded,too).             
             2) If this # was less than the sidewall height of your tire at set up pressure, it means that you have front lift (as jl222 said "eyeball engineering"). At the speeds you're running front tire growth is not going to have a big effect on the tire height.
              3) I think you'll learn more in the tunnel (for the equivalent $$ spent on data acquisition, at least chassis-wise) than buying a data system for next year, unless you've got the $$ to spend on both. I'd gladly discuss this with you (we need to do lunch during the upcoming holiday season, anyway.)
              4) I'd gladly help you with a plan of attack for the tunnel which will optimize your efforts (I do have some experience here), and accompany you to assist.   
               vic 

[Cajun Kid]

Vic,  yes I do have notes (and you know why I keep some data to myself)....

and yes when I go to the tunnel I will need some help and will keep you informed.

Call me and we can grab lunch next week or the following...

Charles