Best ratio of front and rear downforce???

[Payne]

I'm undertaking a project to put some real wings on my Atom. I'm working with Circo Design, which does the aero for many of the SCCA national champions in autox. http://cirodesignracing.com/CiroDesignRacing/WING.html

The one big question we have is what is the right downforce balance between the front and rear of the car. IE if I have a wing in the back that is giving me 500lbs of downforce at 100mph, do I want 200, 300, 400, or 500lbs up front? Anyone with a lot of experience/testing have any thoughts? I think you could also use downforce to help with cold tire understeer on cold tracks and morning sessions as well.

Also, is there anyone that would be interested in a serious wing setup for their car? I would think we could do a full solution to get you very clean aero adjustible from able to support very high speed tracks to a very high downforce setup for autoxing. Depending on what it costs to fab the mounts, I bet it could be done for around half of what Ariel/TMI charges, and a lot more effective.

Jason

[bolus]

I dont think we really know. We have one official wing with a few reports of improved lap times and just the computer modeling that Brammo did when they designed them. No one has done any solid testing.

You may need to ramp up the spring rates for that kind of downforce too

[Payne]

I dont think we really know. We have one official wing with a few reports of improved lap times and just the computer modeling that Brammo did when they designed them. No one has done any solid testing.

You may need to ramp up the spring rates for that kind of downforce too

I really have no idea what would be optimal downforce for the car. I think the front of the car is free downforce becuase the drag is going to be absorbed by the chassis anyway. If it takes 10hp to offset the drag loss of a rear wing at 120mph, is that going to lower lap times? I don't know

My goal of the project would be to make the car safer on the street with a fairly agressive angle of attack (20ish degrees) to give me optimal downforce numbers around 50-60mph, but the ability do drop the wing all the way down to 10 degrees or so for big fast track days.

Good point on spring rates, I'd have no idea how much I'd need to come up. I do know from talking to TMI that they do see measurable squat on their test mule with the factory wing setup.

[MadMaxAtom]

I have to rely on my butt-o-meter...which tells me after experimenting with no wings,one wing and both wings..both brammo wings are helping at speeds over 90mph...enough to want them on the car.

...and it feels like more downforce would be even better...but not tons more... and the wings can't look like shit.

I believe 2-300lbs on the nose and 5-600 out back would be ideal for Max's current suspension setup and tire combination..depending on the track and conditions. That would load the suspension and tires nicely...from what I have measured. ( I currently run 300lb springs up front and 550lb out back on custom built Moton shocks and Palatov rockers/pushrods/spindles.)

I am wondering what the addition of the windshield is going to do to the feel of my Doc Atom at 100+ mph.,as it looks like it could be dumping a lot of dirty air on the back spoiler,..don't know for sure without a wind tunnel..and that's not happening. Long wait till spring...