Big Aero

[stradman]

I'd have to guess nobody in Global Time Attack or similar programs have access to wind tunnels, it's all done by trial and error with lap times. They obviously know what they are doing.
The guy that owns this car is a good friend of mine, his shop works on my car, he built all this with his own hands, no wind tunnel, just lap times and his car will smoke mine or any other car on this forum-
https://motormavens.com/ums-tuning-c...er-lap-battle/

Sure trial and error could help, but very often they throw a lot of things at the car at once and don't always understand whether a specific mod was actually that helpful. Also as these things individually usually contribute fractions of seconds of improvements or not, variations in atmospheric conditions also may throw off any assessment of aero mods. Thats why wind tunnels are the only standardised way you can tell.

[Arizona Vipers]

Sure trial and error could help, but very often they throw a lot of things at the car at once and don't always understand whether a specific mod was actually that helpful. Also as these things individually usually contribute fractions of seconds of improvements or not, variations in atmospheric conditions also may throw off any assessment of aero mods. Thats why wind tunnels are the only standardised way you can tell.

I guess more than overall lap times, I mean data. Like when I was at COTA a couple years ago, I had the privilege of watching Gspeed and Paul Costas build a front splitter for the infamous "SLJHMR" C5. They spent the entire weekend changing the splitter size using pennies worth of spare junk they had lying around, but made the car much faster. They compare corner speeds and speeds through the S's, versus MPH lost on the straights etc. This car run 2.23 at cota that weekend with 280whp just relying on heavy aero, and light weight. They were 2 second off my stock ACR that weekend and my time broke the Texas Nasa TT1 track record with half the horsepower lol. It's not hard to see what aero changes make your car handle better. It's just like when you change wing settings. Set your wing to #1 and to #4 back to back and you won't need a wind tunnel to know #1 is faster and car is handling better. Cheers

[ViperTim]

I guess more than overall lap times, I mean data. Like when I was at COTA a couple years ago, I had the privilege of watching Gspeed and Paul Costas build a front splitter for the infamous "SLJHMR" C5. They spent the entire weekend changing the splitter size using pennies worth of spare junk they had lying around, but made the car much faster. They compare corner speeds and speeds through the S's, versus MPH lost on the straights etc. This car run 2.23 at cota that weekend with 280whp just relying on heavy aero, and light weight. They were 2 second off my stock ACR that weekend and my time broke the Texas Nasa TT1 track record with half the horsepower lol. It's not hard to see what aero changes make your car handle better. It's just like when you change wing settings. Set your wing to #1 and to #4 back to back and you won't need a wind tunnel to know #1 is faster and car is handling better. Cheers

This is basically how F1 teams did before windtunnels and stuff.
And how many amateurs still do it today.

Not everybody can afford a wind tunnel. And a wind tunnel isn't a must either.
Can be done the hard way, just way more time consuming and difficult.

[Arizona Vipers]

This is basically how F1 teams did before windtunnels and stuff.
And how many amateurs still do it today.

Not everybody can afford a wind tunnel. And a wind tunnel isn't a must either.
Can be done the hard way, just way more time consuming and difficult.

Or like this LOL- https://www.youtube.com/watch?v=EjbhBBJ-mfY

[13COBRA]

Or like this LOL- https://www.youtube.com/watch?v=EjbhBBJ-mfY

Haha I was hoping that's the link you were posting.

[ViperTim]

Or like this LOL- https://www.youtube.com/watch?v=EjbhBBJ-mfY

LMAO exactly what was on my mind while I was typing that!

[TrackAire]

Here is probably an even more useful tool to collaborate real world data with what is shown in the wind tunnel or CFD models.

https://www.youtube.com/watch?v=sVU1-zSrqvM

One of the problems with a wind tunnel is just that, a tunnel has a "wall" on the sides and top of the car. On the open track, the car has essentially has no sides or "roof" to limit the compression of the air molecules. The compression of molecules against the walls of a wind tunnel can cause a different effect compared to what the car is doing when it is 100' or further from a fence or track wall, etc.

Mixing a homebrew of fluorescent powder and a light oil can let you know what the air is actually doing against the car in more real world conditions. Helpful in F1 or other top tier racing where the top three cars may qualify within a hundredth's of a second of each other.

For me, it would just remind me of a bad LSD trip.

[Pappy]

Or you could build your own (95 mph limit - all the tow truck would do) wind tunnel. LOL It isn't very accurate, but it helped me find the clean air for the wing and the really dirty air where the roof met the windshield.

Pappy

56 Wind Tunnel.jpg

[TrackAire]

Or you could build your own (95 mph limit - all the tow truck would do) wind tunnel. LOL It isn't very accurate, but it helped me find the clean air for the wing and the really dirty air where the roof met the windshield.

Pappy

56 Wind Tunnel.jpg

First ever wind tunnel to get a speeding ticket......lol.

[TKO MOTORSPORTS TEAM]

What Stradman said :

"with any aero mods. Unless you can test the
car in a proper wind tunnel some of it may not actually be as functional as we think"

Agreed Steve wind tunnel testing is the best and most cost effective but 500.00 per hour for cheap static wind tunnel testing is not in most amateur racing budgets There are wind tunnel work arounds and good basic aero principals that many of us professionals use that have worked for decades. Alot of these time attack cars could be alot better designed and engineered for sure; But its always good to see people working with what they have and trying things. Professional motorsports use to be about innovation and competition but now its all about homologation.