We Challenge You!

aussiesmg wrote: $2015 class should be mandatory

That would interest me. April is just around the corner and we have a lot to do if this happens.

SVreX wrote: 90 seconds per car- Do we get more that 1 attempt, or is it all or nothing in 90 seconds? Are we at least saying production cars, or is it open to motorcycles, go karts, unicycles, and lawn mowers? I certainly think there should be a class for Challenge cars, but would rather not restrict the budget. I intend to bring a $2014 Challenge car which is returning for 2015, but would like to add some things which will not be on it at the Challenge. Don't want to have to fool with the budget. "SCCA classes" is not descriptive enough for me. I don't autocross very often, and have always struggled trying to figure out the darned SCCA classes.

PLEASE NOTE THIS IS ALL UNOFFICIAL. WE'VE BARELY EVEN HAD MEETINGS ABOUT HIS YET.

90 seconds per attempt. As many attempts as the event allows. Exact format will depend on number of entries (heats, etc), but the idea is that you should be able to make tweaks and changes at some point and try again.

Not necessarily production-only, but our insurance may not cover anything with fewer than four wheels.

Challenge car class is a good idea.

SCCA Street: Shocks, front OR rear bar, alignment (no grinding), 200TW tires

SCCA Street Touring: Shocks, bars, springs, bushings, wheels and tires restricted sizes but larger than stock, 200TW tires, no moving suspension pickups or grinding.

SCCA Street Prepared: Much like Street Touring but with R-comps, unlimited wheel and tire sizes

SCCA Prepared: Slicks, gutted, moved pickup points, extensive lightening, suspension largely free inside original design parameters (coils much remain coils, etc).

SCCA Modified: Tube frames, heavily modified tubs (different suspension design, etc), slicks, sports racers, formula cars, aero, alternate materials.

Again, these are broad swaths.

BUT PLEASE REMEMBER THE MAIN MESSAGE:

We want you too feel like you can express your creativity. If you want to build something with a sail and outriggers so the driver sits in the center of the circle, by all means do it. Unfortunately, the best way to make classes for this thing would be to wait and see what shows up, then decide. But that would anger people.

Umm... we had actually already (seriously) discussed a sail, outriggers, AND the driver sitting in the center of the circle.

Weird. Are you channeling Mr. Joshua or me??

I don't think you will have enough entries to have all those classes.

Thanks SO MUCH for the brief SCCA overview!

Best clockwise and counterclockwise laps from one heat.....or best of each throughout the day? I like awards for each, it encourages two different styles of builds.

MrJoshua wrote: Best clockwise and counterclockwise laps from one heat.....or best of each throughout the day? I like awards for each, it encourages two different styles of builds.

We'd probably do one or the other, at least for the first year. We're basically expecting small autocross turnout numbers for this thing, with maybe half a dozen specific builds and the rest being existing AutoX/Race/Street cars. We may be pleasantly surprised, though.

My pick would be best CW time of the day + best CCW time of the day, whether they're in the same run or not, would make your score. But you MUST make runs both directions every time you enter the ring of doom, even if one direction is at substantially reduced speed. Cal it a "proof of concept" run. Again, that's just my idea.

Basically we see this big variables in classing thusly:

Street Tires, R comps, slicks, bolt-on chassis bits, bolt on chassis bits with different pickup points, modified chassis or different that delivered suspension designs, tube frame cars, sports racers, formula cars, aero cars, freaks.

Those main bits are roughly housed in each of the SCCA's autocross divisions, which is why I'm lobbying for some breakup of classes loosely divided along SCCA Solo lines.

I'd rather see best CW + CCW in the same run.

Otherwise, we can spend 4 hours reversing the setup, which negates the point of doing it both ways.

Can a vehicle be as wide as the diameter of the circle?

slow wrote: Can a vehicle be as wide as the diameter of the circle?

Sure. Send us a picture of your trailer, too.

SVreX wrote: I'd rather see best CW + CCW in the same run. Otherwise, we can spend 4 hours reversing the setup, which negates the point of doing it both ways.

Agreed

Two motorcycles connected by a cable. In reply to JG Pasterjak:

slow wrote: Two motorcycles connected by a cable. In reply to JG Pasterjak:

Interesting physics experiment, but I don't think you'd ever get it to work in reality. A 200' circle is an awfully big length of cable. And remember it's likely going to be defined by pylons on the inside. But even if it wasn't, the challenge of precisely matching speed AND radius would be nearly impossible.

But this does answer the question of "How do I make a motorcycle more dangerous?" Simply by connecting it via death cord to another motorcycle.

In reply to JG Pasterjak:

Ok for safety, I will think about padding the cable with some foams.

Maybe connecting two cars together would make things sounds safer. Don't know if It is possible to get ECUs to match RPM.

Yeah. Throw some foam on there. That'll make it way safer.

I just think the physics are too much to overcome in a practical manner. The physics would be sketchy enough if you were tethered to a fixed point. Anyone with a Cox gas powered car in the 1970s knows that'll work to some extent.

But you're tethered to a moving point, with an inflexible connection. And that moving connection also has mass, and therefore angular momentum. I think this would be a hard enough problem to solve for two spacecraft, that don't have to worry about X axis issues or drift. But you have not only the problem of keeping the vehicles equidistant, and equally velocities, but also keeping them within the confines of the lane.

If one of the riders has more donuts for breakfast, he'll have more momentum, and be pulling the other guy toward the center.

Will a passenger be allowed? Specifically, a minor (with signed waiver of course). I think my 11 year old son would enjoy riding.

In reply to GPDren:

I'm pretty sure GRM will say it is a decision the track officials will have to make based on safety policies and their insurance.

We used to have students riding shotgun at the $20XX Challenge. This year, the track officials said no passengers who did not have a driver's license.

It's gonna depend on Road Atlanta.

So im still stuck in cprepared. Dammit. Gonna get my heas handed to me.

But ill have a blast on the bench seats.

Is there a way we could maybe get bikes in with a displacement limit? A pitbike class would be hilarious... and a pitbike with a sidecar and a monkey would be amazing

From what I can find, the Road Atlanta skidpad is 250' in diameter. Pretty small, I think they're usually twice that size. 43 mph will get you 1g. That's fast enough for aero to work, but it'll have to be fairly big aero. Still, when Racecar Engineering put a Formula Student (UK version of FSAE) car in a wind tunnel, they found downforce equivalent to 13% of the car's weight at 40 mph and 28% at 60 mph. That's significant, as it should increase lateral grip by a similar amount.

I think power is being underrated here as well. You're fighting against a lot of tire scrub as well as (potentially) big aero drag, so you won't want to do this with a minimal motor. I'm not saying LS3, but you'll want enough power to be able to adjust the line as well as overcome the drag.

I found one comment about the R&T challenge referencing a sucker kart. With a leaf blower for suction, it stapled the kart to the ground so hard that the main engine could only manage a walking pace.

I also found this article about the 1985 R&T event. Check it out, there's some guy named JG driving a Neon.

http://forums.vwvortex.com/showthread.php?5804484

We had an actual meeting today (see, we actually do work sometimes), and hashed out some rules proposals. The official proposal will be posted in a few days, but basically we're talking about breaking things down as I mentioned in a previous post, by SCCA Solo categories, with some allowances for unlimited machines. We're also adding a clause that we can condense or further subdivide classes based on subscription. This proposal will be posted for discussion soon, and we'll try and finalize them right after the first of the year.

This seems like a pretty reasonable structure, though. If you look at the old R&T article, the biggest divider between the cars was tires. Pretty much everything on street R comps was in a small range, slick cars were within a small range and the only real difference was with the unlimited cars—and that was mostly dependent on how well their tricks worked.

That kart was cool. His sucker worked so well he spent most of the day cutting holes in his skirt so he could actually get the thing to move. The first time he fired everything up he couldn't actually move it at ll because it sucked so much.

And Keith is right about power. Tires produce their maximum grip at a certain slip angle, and you have to have the power to maintain that slip angle and overcome the angular friction. Manageable power and a predictable throttle will be an asset.

You're gonna have prize money like R&T offered right? Adjust for inflation, carry the one, ....

This is going to be such a hoot. Great idea!

Think of the oil starvation!

I would LOVE to build an electric cart with 335 section width hoosiers at all 4 corners, huge wings and battery packs inn the floor. Sort of similar to what JThw8 is doing but electric.

Lowered like this but with wings, a hard top, and big grippy meats. Or maybe with no suspension at all since the skid pad will be a very smooth surface. Hmmm...