beetle and aero

[Gerrelt]

@Wally: I am glad you still like them!

I am working with Gerrelt to create the large roof extension seen on some of the Cup cars like Thomas' to increase stability at top speed even more.

Shall I post a picture of the mockup?

This originates from the Porsche world. The ones for 911s reduce drag, and reduce wind noise.

Do they make them for 1300 Beetles?

AFAIK, Gerrelt only made a version for the curved windshield, but maybe he can be pursuated if demand would justify cutting up an A-pillar from a flat windscreen beetle to make a new mould..

Yes, what he said. Creating the mold is a bit time consuming. It's hard to get the mold perfectly flat. The ones I am selling now are a bit experimental, and require a bit of work to get perfectly smooth.
And, indeed, it would mean buying and cutting up an flat windscreen frame.

We did some testing this weekend with wool. Yes it is a primative way of checking aero, but I do not have access to a wind tunnel

The first run was without the roof tab.

without tab on roof.jpg

The second with a tab on the roof to try and reduce the drag

with tab on roof.jpg

Now, I am no expert in aero, but what I did see was that the tab did deflect air from the rear windscreen. The first run the wool stayed flat onto the windsreen torwards the bootlid. The second run the wool went torwards the tab.

Any comments??

I think your tab is quite high above the rear window, or is it just the camera angle that's making it look like that?
Do you have more pictures of your "tab"?

It's nice to see your wool tuft test looks a lot like mine. At my tests, the wool tufts were pointing upwards with the spoiler too.

The data logger did not give much evidence that it is working.

I noticed my fuel consumption is pretty good (low consumption). I managed to average 1 liter to 13 kilometers while traveling at high highway speeds (140 km/h) and mixed with a large traffic jam and hilly B roads, loaded with 2 adults 2 kids and luggage for 4 nights.
But, I don't have really something to compare it too, before I put the spoiler on.

That's what I wanted to hear!
How is it held in place? It looks like it wraps around the drip rail, then the window rubber holds the other side.
Or is there glue involved?

Here is the "instruction manual".

[Piledriver]

I wonder if those would fit a Type 3...?
(about the same windshield angle etc)

[Gerrelt]

I would be very surprised if it fit. The shape is pretty specific.

[Wally]

I am working with Gerrelt to create the large roof extension seen on some of the Cup cars like Thomas' to increase stability at top speed even more.

Shall I post a picture of the mockup?

Sure, no problem with that

[Gerrelt]

This is what I am trying to build for Wally:



Obviously this is a mockup made out of cardboard. I want to create it out of plastic, which can be shaped by heating it.
The spoiler will be attached by screws through the spoiler into the roof. I think I will call it the "Airspeed" spoiler..

[volksbugly]

While trying to find out how to book time in a wind tunnel at NASA-Ames I came across this.

http://www.grc.nasa.gov/WWW/k-12/airplane/tunwtest.html

enjoy!

[buildabiggerboxer]

I just make them from ally sheet, no point in a pic, you cant see them on a black car.

[pickstock]

Hello guys dont mean to disrespect the Thread or the thread starter but this is the only topic I cound find about aerodynamics that is still active.. I just have a quick question..
Ive been lurking the forums for quite a while already. I have read tons of comments, ideas and knowledge regarding aerodynamics in vw. As many may have confirmed it already they say that aerodynamics for a VW beetle does not kick in till like your prolly running at 80mph - 100mph (correct me if im wrong). Anyways I have a 1974 1500cc beetle (brazil) and the fastest that I have gone so far no matter how hard I throttle was 74mph and the max speed in my speedometer is 86mph. So my question is If I made a few modifications to my bug in the aerodynamics side (Herod Helper or the equivalent, front spoilers and grill opening on my 4 fenders etc...) will It be able to aid me to attain a higher speed and not just get stuck at 74mph? by the way the back part of my bug has a little opening at the

I also would want to know if that "opening" will increase drag or assist in reducing drag?

THanks so much...

Sorry for the late reply

Basically thats horrible for drag, and probably lift.
Aero might not be your biggest problem it might be lack of power, my modified suzuki would only do 140 kmh, ever.....
That was with twice the horse power over original and just over half the weight but in 3rd though to 5th it sat at 140

Also I'm going to start doing some work to my superbeetle and get it sold

[Copbait73]

New to this forum.

I'm returning to my roots and working on a '71SB. Still own a couple of early 911s so not intending it to match them but it must be competent running at 75-80 mph for hours.

Also have a 2000 New Beetle TURBO with the spoiler only briefly mentioned here. Somewhere I read it has auto extension at 84mph (plus closes the sunroof if open) but also has manual extension. I can tell you it is very effective. The car settles nicely in cross winds and the turbulence behind and passing trucks. The first thing I do after merging on to the Interstate is set the Escort radar detector on the dash and deploy this spoiler. You guys who are working on a similar spoiler for the T1 are on the right track.

There is also much debate in the Porsche community if the car actually corners better. I am not a racer but I tend to accelerate on high speed ramps and sweepers. My N Beetle and spoilered 911s feel planted in this situation. I like that, tail out at 90 plus is not my thing.

[Piledriver]

Welcome to the STF!

There is no doubt in my mind at least, you certainly don't need an outlaw sprint car wing to make a noticeable improvement.

Simply having decklid standoffs on my sons 71 SB and dropping it just a tad over 2" made an insane difference at stupid speed (that and reasonable rubber, even on 5.5 mexi rims)

The GTi duckbill on my squareback feels like I tossed 2 bags of concrete in the frunk. Rock steady at speed, no truck blast or crosswind issues anymore. Without it just following a semi at a reasonable distance on the freeway it blew all over the road.

[pickstock]

I used to think most wings were a waste of time
Until we towed a Nissan rally car in reverse, the trailer wiggled all over the place

[richie,uk]

I used to think most wings were a waste of time
Until we towed a Nissan rally car in reverse, the trailer wiggled all over the place

That is usually caused by having the weight at the wrong place on the trailer more than an aero issue

[Sgresuuu]

hello i'm an italian guys and i want to buy a fun cup wing someone knows who sell it?! thank you

[buildabiggerboxer]

you have to be a registered fun cup team to buy any parts, but no need to buy a workmate to bolt on the back anyway, the best aero performance is free and nobody uses it, its called ground effect and it will work for you at 40mm ground to pan clearance, no cost, no weight, no drag, no kidding.

[yodogg]

Hey BBB,

Unfortunately, 1.6" of ground clearance isn't terribly streetable, or did I misunderstand?

Despite what I just said, we did manage to drop our super beetle's rear a couple of years ago such that the deep sump was down to 1.75" of clearance (rear shocks were down to a little less than 2" of travel). However, ground to pan was something closer to 3" (76mm). The hardest part was getting it on and off of the trailer, otherwise it handled well on the track (both the body and suspension was very stiff) in all situations outside of the most acute turns- but that is a discussion for a different forum.