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Gentlemen,

According to Sports Car Graphic, Spt. 1969 issue, at 100MPH,

The Bug has 150lbs of lift in the nose, and 0lb at the rear. Total drag is 370lb.

The Ghia has 160lbs lift in the nose and 70lbs lift in the rear. Total drag is 320lbs.

And the winner is:

The Type 3 Squareback with 60lbs front lift and 70lbs rear. Total drag of 340lbs.

We specially videotaped our Ghia at 100mph+ just to record front nose rising. It's there. The Bug does the same. I am not aware of any factory-intended nose lifting on either body type, Bug or Ghia. I tend to think the report of it may be a misunderstanding.

I cannot see any provisions in the suspension to encourage nose lift, as the front trailing arm system geometry does not resist nose dive under braking or nose lift from aerodynamic forces.

The Bug and Ghia nose lift numbers show how important a front air dam is to reduce the lift, and anything you can do to break the drag (rear spoiler) is good for top speed.

FJC

I have found that a bug with the front about 1 inch higher than the rear handles better. I'm not sure why. I race my Ghia this way in autocross and on the track and it works well. To me it makes the car over-steer more controllable and virtually removes under-steer. I was always surprised when people complained about their bug under-steering, I have never had that problem.

For drag racing I don't know whats best.

FJCamper wrote:And the winner is:

The Type 3 Squareback with 60lbs front lift and 70lbs rear. Total drag of 340lbs.

Any idea why the squareback had such a significantly lower front lift? The front looks very much like a Ghia. It even looks like it would force some air under the car.

Theo wrote:I have found that a bug with the front about 1 inch higher than the rear handles better. I'm not sure why. I race my Ghia this way in autocross and on the track and it works well. To me it makes the car over-steer more controllable and virtually removes under-steer. I was always surprised when people complained about their bug under-steering, I have never had that problem.

For drag racing I don't know whats best.

Did the handling suffer at all? Did it improve characteristics at ALL speeds? Perhaps, the height difference is more of a suspension trick than aero.
How did you achieve the difference? Lower the rear; raise the front; lower both but the rear 1" more; etc.

The handling improved at all speeds. I don't think it has anything to do with aero but more with steering geometry and inertial momentum. At the very least it adds caster to your alignment.

I have adjustable spring plates and front beam. I have played with all sorts of settings. I have both the front and rear lower than stock with the front 1 inch higher than the back. I have 14 inch rims with low profile tires, the Ghia sits low.

The rake looks a bit stupid, it looked better with the rear raised up but it handled like crap that way.

I just set my Baja up the same way and it handles great.

ProctorSilex wrote:

Theo wrote:I have found that a bug with the front about 1 inch higher than the rear handles better. I'm not sure why. I race my Ghia this way in autocross and on the track and it works well. To me it makes the car over-steer more controllable and virtually removes under-steer. I was always surprised when people complained about their bug under-steering, I have never had that problem.

For drag racing I don't know whats best.

Did the handling suffer at all? Did it improve characteristics at ALL speeds? Perhaps, the height difference is more of a suspension trick than aero.
How did you achieve the difference? Lower the rear; raise the front; lower both but the rear 1" more; etc.

FJCamper wrote:Gentlemen,

According to Sports Car Graphic, Spt. 1969 issue, at 100MPH,

The Bug has 150lbs of lift in the nose, and 0lb at the rear. Total drag is 370lb.

FJC

Hi FJ

0lb lift at the rear? Is that correct?

Hi Tony,

Yes, Zero rear lift on a Bug. Sports Car Graphic had the VW's analyzed in response to Nader's UNSAFE AT ANY SPEED comment's about the VW. That was the book that killed the Corvair.

Running a swing axle Bug or Ghia just one inch lower in the rear than front does help the handling. Aircooled.Net has a handling setup tech article in which this is specified, and I have seen it for myself. I believe it is because the rear roll center is lowered.

FJC

OK, I'll admit, I am a little confused now. Zero lift at the rear of a bug at 100mph. Even though the car basically works like a wing at high speed.
So with items like a wing or small Remmele spoiler on the roof, is the aim to reduce drag and not actually worry about rear lift?
And then the airdam in the front is to reduce air entering under the car and lifting the nose?

ProctorSilex wrote:

FJCamper wrote:And the winner is:

The Type 3 Squareback with 60lbs front lift and 70lbs rear. Total drag of 340lbs.

Any idea why the squareback had such a significantly lower front lift? The front looks very much like a Ghia. It even looks like it would force some air under the car.

It's not only the bottom of the car that controls lift.
Wings have 2 sides.
There's a reason a late squares front end looks vaguely like it came off a boat.

The T3s likely spent a lot of time in the wind tunnel during early design/development in the late 50s.
The whole intent was to fix the shortcomings of the beetle, more room, better ride/handling (esp at speed), probably safety.

The bug was a child of the 30s that VW couldn't really alter too much as it was the bread and butter.
The Ghia was a classic design off an artists drawings, esp with the Ghia aero was secondary.(but I'm sure it got some attention)

T3 was essentially a clean sheet (exterior) design, so they could do aero right.

Thinking about it, I think read about the ~1" stagger height change on the Beetle in one of the VW history articles many moons ago.
(probably pre-google) in a Magazine or book, it covered the wind tunnel work that was done, and how it affected later cars.

Same article also said the beetles aero was very significantly better... backwards.
I'm reasonably sure at least one racer tried it & got their creation banned for trying it and screwing with other drivers minds...

I want to say the "change" was in ~60-61.

The Notch has a cD of .34 IIRC, comparable to more than a few 2011 models, and about the frontal area of a Prius.
Square is a little higher at .37, still respectable for a wagon.
(There's some data floating around on T3 aero, a nocth with a rear spoiler of sort and small front spoiler looks like a winner, an early notch would probably make for a great race car if they weren't as rare as hens teeth)

FWIW I run at stock height, but the ridiculous ~4" deep Mk1 Golf spoiler I run on my square makes a HUGE difference on the highway as to blowing around from truck turbulence and crosswinds. I'd lower it, but I actually haul stuff/drive it ~80 miles a day.

@FJCamper, thanks for posting this:

FJCamper wrote:Gentlemen,

According to Sports Car Graphic, Spt. 1969 issue, at 100MPH,

The Bug has 150lbs of lift in the nose, and 0lb at the rear. Total drag is 370lb.
The Ghia has 160lbs lift in the nose and 70lbs lift in the rear. Total drag is 320lbs.
And the winner is:
The Type 3 Squareback with 60lbs front lift and 70lbs rear. Total drag of 340lbs.

I found the article online, and I think it's an interesting article. See link: Sports Car Graphic - September 1969 - 10 pages.
Use the "next page" link at the top for navigating to the next page.

Nice article, I especially like this page, the top right corner: Page 7:

Sports Car Graphic wrote: and the beetle a bad last with 370 pounds (drag). Maybe Mr. Kamm (see: Kammback) had something there after all.
According to aerodynamic theory, the rear of the "bug" slopes away too rapidly and the airstream probably separates just below the roof line. Well, anyway, it looks more aerodynamic.

I really like that these findings are the same as autospeed did, but then almost 40 years later! See: Aero Testing - Part 3.


One note though: the aero dynamic measurements were done at 70 mph, because the beetle won't do 100 mph.
They then recalculated the values to 100 mph.

didn't bill fisher test beetle aerodynamics and found that the rear does lift? (as expected)
I have that sports car graphic article and I have always thought there must have been something wrong with those measurements

Above; Note air deflectors under car.

Hi Slow1200,

I referred to the Sports Car Graphic article data, but only as their data.

Fisher cites in his "Stability and the Beetle" chapter (pg 141) of his original "How to Hotrod VW Engines" 68lbs of rear end lift on the Beetle body at 75mph, extrapolated to 136lbs at 100mph.

The numbers are from Paul Lamar, introduced by Fisher as a noted aerodynamic expert from Manhattan Beach CA, and I do not doubt his findings. Sports Car Graphic was one publication that used Lamar's information, but I don't know if Lamar had any input in the "Why Would Anyone Buy A VW" Sports Car Graphic article in which zero lift on the Bug rear end was quoted.

I went back and reread the Fisher chapter today, and it appears to be the source of the info that VW slightly raised the front suspension of the Bug (swing axle) to increase front lift and decrease rear lift.

We get all this info from different publications, but in the end it is application on the racetrack that matters. My own experience with aerodynamic extremes is with the 1973 Super Beetle IMSA car we had back in the mid-1970's which we ran at the Talladega Super Speedway for the closed-course speed record for a stock-bodied VW. That means no aerodynamic aids.

And we ran an engine that would have been illegal in IMSA B-Sedan. This was a speed record engine.

Our car could briefly touch 130mph+ on the straights, but didn't have the power to stick in the banking more than a third of the way up. And it was a handful. We had lots of rear lift that translated into the tail losing adhesion and trying to pass the front, so we were "crabbing" sideways at times.

We had a full pan but had cut away all the interior bodywork and tried to vent out air pressure filling the car's interior with holes venting to low pressure, etc.

We finally fitted deflectors (legal) that were supposed to divert air to the front brakes, but we were trying to use them as an improvised spoiler to block some air from underneath us. It helped. The car was more controllable, and picked up some speed lost to the crabbing.

FJC

Hello.
The reason to why the beetle generally handles better with the front raised 1" over the rear has more to do with the general caster angle. The older recommendations state that the factory caster angle (2,5-3,5 degr.) is sufficient to 100 mph. I do not agree. - All things equal, the beelte (not the super) handles much better at 4 degrees. Even an otherwise stock.
when we begint to lower the cars and furthermore adjust them to a nose down stance, the caster angle is heavliy affected. In some cases it goes down to 0. and if youre in luck to have replaced the stock front beam with a repro, it can be even worse. Then the car is a handfull even at 55 mph.

Again, all things equal, a beetle, lowered up to about 1" in the rear and about 2" in the front, set up with 6 degrees of caster, runs straight as an arrow at 105 mph. After that it begins to be slightly "alive". Same car with 8 degrees of caster runs straight to at least 120 mph.
But it IS the complete package that makes the difference. Sometimes you run into a car that just not drives well at normal settings. Then its time to inspect everything. Last time it happened to me it turned out that one of the front trailing arms were bent. Took me a while to figure that out.

T

thought i would stickl my car up on this thread to hsow what i have done and how it effected the car

IMG_0180 by robjudge1313, on Flickr

IMG_0162 by robjudge1313, on Flickr
on the 1/4 mile i have done back to back tests with and with out the rear wing and front air dam/splitter. it made no differnace to the times at all 14 dead and a best of 13.98 with all the areo parts on the car.
on the track the mod's made a big differance with the stopwatch, at Prescott hill climb it made a 4 second improvment over the mile long track. the car is so much more stable at speed [max speeds of 80mph] and the differnace in front end grip is allmost unbelivable. my fornt tyre temps went up by 10* across the tyre on the mile run, so there getting worked much harder.
i have run the car with out the rear wing on the drag strip with no problems untill i lifted after the finish and the car tryed to swap ends.
the rear wing has also bent the panel it is mounted on, the slotted panel under the rear window. it bent by nearly 25mm and i had to make up some new mounts that tied in with the deck lid hinge mounts to stop it flexing.
the front splitter ripped the first mounts i made for it, 3mm alloy plates that bolted onto the bumper mount panel, there now 5mm thick alloy plate and have been fine.
areo can and does make a real world differnace on our cars, it dont look pretty but race cars are ment to be fast.
cheers rob

judge wrote:

Please tell us more about the other things on the front end besides the air dam. I have seen the ones under the head lights before, but never the predator jaw pieces at the outside ends of the air dam.