Black Ops for the '04 Open Track Challenge

[}{arlequin]

cooling and/or suction?

[Tyson Schmidt]

Eric, the front bumper and splitter are not lower than the belly pan anyway, so there is nothing to try to keep from spilling. If we ran a deep front airdam, then that would definitely be a consideration.

The picture is an opticalk illusion, and the sheet ends right at the rear swaybar, so no blockage of the trans is going on. Jack has a trans cooler anyway.

Amir, the bellypan is quite a bit lower than the engine. It's the funny angle of the picture that makes it look like the engine is hanging low. It actually looks way better on the hoist in person. Looks very F1!

We'll have to do some back to back runs at Willow to see how effective it is at reducing drag.

BTW, if it does alter the downforce distribution, the rear wing angle can be adjusted to compensate.

[nostatic]

I would echo the worries about picking up air in the front gap (right behind the condenser). I think you need to seal that front edge off, or have something extending from right behind the bumper then overlapping that front edge so it isn't exposed.

I wonder if we can pull your car into the wind tunnel at Caltech...

[Bill Verburg]

Hopefully shaped so not to collect fluids in the center

[Tyson Schmidt]

Originally posted by nostatic
I would echo the worries about picking up air in the front gap (right behind the condenser). I think you need to seal that front edge off, or have something extending from right behind the bumper then overlapping that front edge so it isn't exposed.

I wonder if we can pull your car into the wind tunnel at Caltech...

Yes, all you armchair engineers. We know about the gap, and we had tabs built in so we could strap it up to the body, but they tore.

Our next plan is to install block offs.

[masraum]

I can't wait to hear the results!! (it's just too bad Jack couldn't write himself out of a wet paper bag... )

We should have known that Tyson would have all of the bases covered.

[rattlsnak]

You should run a diffuser tray in the rear also. Look at all the Vipers, Vettes, etc.

[Tyson Schmidt]

Originally posted by rattlsnak
You should run a diffuser tray in the rear also. Look at all the Vipers, Vettes, etc.

Oh man, would I LOVE to be able to do that! But with a rear engined car, it's just not feasible. Porsche did their best with the 964 and 993, but there just isn't enough room for it. You'd have to raise the engine up in the car.

[rattlsnak]

Dont disappoint this entire board,.... Make it happen,..

Im sure a 1 or 2 inch vane would work.

[Jack Olsen]

Yes, the angle of the picture is pretty misleading. The engine is higher than the cover. The front condenser is lower. If you see it in person, you'd see that there is really no way air is going to get between the plastic and the car in front.

The sides, right behind the wheels, are another story. I'm working on a block-off for that -- although the wheels and brake cooling diverters all push air away from the opening. I suspect if we left it open, it would be fine. (But we won't.)

For this event, we need to run street tires with a wear rating of 140 or higher. That means no R-compound anything. Ordinary BFGoodriches. We shaved them last year, but didn't this year, since the competition won't be as close.

[JonT]

Wouldn't a dimpled surface work better than a smooth surface (similar to the Lexus commercial)?

[greglepore]

I think I'd add a smallish rubber lip at the back like the CTR's to reduce the turbulence around the engine, and maybe try to seal the front with some RTV to avoid it tearing off. I wouldn't be concerned about the extra drag if it did start to come off, but the black flag time could put you at a real disadvantge.

[Jack Olsen]

Black flags do not scare us.



Boldly, I predict a first in class in this year's Open Track Challenge.

(Of course, as of this writing, we're the only entry in our class. )

[masraum]

Jack Olsen, you're just too d@mn cool, buddy!!

I wanna be just like you when I grow up!

Unfortunately, the prospect of me ever growing up doesn't look good at this point, so I may just have to endure BB2 envy and leave it at that.

Oh, do you play an instrument, paint and sculpt too? Writing, photography, driving, what artistic endeavor aren't you good at?? (besides not ending sentences with prepositions)

[Tyson Schmidt]

Originally posted by JonT
Wouldn't a dimpled surface work better than a smooth surface (similar to the Lexus commercial)?

O.K., I nominate you to come over and install a thousand thumbtacks into the bottom of the undertray.

[H20911]

having limited knowledge in this area wouldn't it be better to move the air around the outside of the car rather than smooth the air under the car? i would think that it would create more lift at higher speeds.

like an air plane wing the air splits at the front and that air that goes under is fast and dense. the air the goes over has to go faster and is streched out (thin less dense) the differential pressure creates lift. spoilers just disrupt the lift by spoiling the air flow.

more turbulence on the bottom would spoil lift wouldn't it?

good luck on the challenge......looking forward to a good read on the events Jack.

[Jack Olsen]

Originally posted by masraum
Jack Olsen, you're just too d@mn cool, buddy!!

Actually, Tyson's the cool one.

[nostatic]

Originally posted by JonT
Wouldn't a dimpled surface work better than a smooth surface (similar to the Lexus commercial)?

I smell a Titlest sponsorship...

[Jack Olsen]

Originally posted by H20911
having limited knowledge in this area wouldn't it be better to move the air around the outside of the car rather than smooth the air under the car?

Yes and no. With a big, low front end, you move the air out of the way in advance -- but you also increase your frontal area, significantly. With twice the horsepower, this wouldn't matter so much.

But more essentially: I tend to go spinning off the track a lot, and low, aerodynamic front ends tend to get sheared off.

A past experiment:



And after:

[Tyson Schmidt]

Originally posted by H20911
having limited knowledge in this area wouldn't it be better to move the air around the outside of the car rather than smooth the air under the car? i would think that it would create more lift at higher speeds.

like an air plane wing the air splits at the front and that air that goes under is fast and dense. the air the goes over has to go faster and is streched out (thin less dense) the differential pressure creates lift. spoilers just disrupt the lift by spoiling the air flow.

more turbulence on the bottom would spoil lift wouldn't it?

good luck on the challenge......looking forward to a good read on the events Jack.

I think you're missing the point. We're going after faster lap times by reducing the overall drag. Downforce isn't the limiting factor with Jack's car, since we can go flat-out through most high-speed sweepers.

With the wings and flares, Jack's car is burdened by lots of drag, which is costing us a lot of pulling power down long straights. The Viper and 'Vette guys spank us down the straights, even though we kill them in the corners. Just trying to get some of the top-end speed back.