New beetle tdi 5 speed

[razordave]

Originally Posted by aerohead

I looked at the 'visor' at as much magnification as I could get, and it appears that the forward leading edge is 'open' to the airstream. Is that correct?

You are correct. I did not know about the air flowing forward. That could explain that previous tank being horrid.

If I reinstall the visor, I will tape the leading edge. The mounting hardware caused this gap. Attached is what I thought could be a slick easily removed mounting solution.

Free beard, I couldn't remember where I had seen a similar setup but had actually reviewed basjoos thread last night when I decided to begin planning a boat tail or at least a truncated one.

Did I read somewhere that 40% will give you 80% of the benefits?

Lastly, I got a lead on an estate with old airplanes. I may blow a circuit with a body swap on the old tdi..

Edit: it has been done with a pickup chassis and a delivery truck chassis and I'm sure a few more.
https://youtu.be/DHyZPVOT1xI

After having seen some people chop up a beetle to build small campers...

[aerohead]

Originally Posted by razordave

You are correct. I did not know about the air flowing forward. That could explain that previous tank being horrid.

If I reinstall the visor, I will tape the leading edge. The mounting hardware caused this gap. Attached is what I thought could be a slick easily removed mounting solution.

Free beard, I couldn't remember where I had seen a similar setup but had actually reviewed basjoos thread last night when I decided to begin planning a boat tail or at least a truncated one.

Did I read somewhere that 40% will give you 80% of the benefits?

Lastly, I got a lead on an estate with old airplanes. I may blow a circuit with a body swap on the old tdi..

Edit: it has been done with a pickup chassis and a delivery truck chassis and I'm sure a few more.
https://youtu.be/DHyZPVOT1xI

After having seen some people chop up a beetle to build small campers...

Presently in England, Jeff Powell and his merry associates are reinvestigating the drag reduction mechanism of streamlined boat tails at Loughborough University.
What they're experiencing is that, the drag reduction tracks directly, as a function of the change in wake area. It's virtually linear.
If you know the actual wake area of the new Beetle, at Cd 0.39, and you want Cd 0.195, then, the wake area of your tail needs to have 50% of the original.
Carl Breer did this in 1934, on the Chrysler Airflow, with a Desoto Airflow test mule of Cd 0.51, which had a aft-body very similar to the original VW Beetle.
By transforming the ducktail into a truncated kammtail, of no added length to the car, the Cd fell to Cd 0.268.
Then adding about 36-inches of stinger onto the kammtail, drag fell to Cd 0.244, essentially rendering the Cd of the 2012 Tesla Model S, in 1934.
So it's not the 'length' of the tail that you're interested in, it's it's wake area.
Technically, if you were completely nuts, and optimized every area of the Beetle, and then threw a full tail on it, you'd be 'wake-free', and drag would be reduced to only surface friction. Pressure drag would be completely eliminated. What Wolf-Henrich Hucho says is what 'aerodynamics' is all about.
And the contour of the tail needs to be in the 'Goldilocks Zone' right at the front door of separation. Any 'shorter' and it's a pressure fail. Any longer and it's a skin friction fail. You want the contour to minimize both pressure drag and surface friction drag.
Hucho gave us enough crumbs to find our way back to that shape.

[freebeard]

' no cost'

I was thinking of a 3D model. The one I have is mid-poly, not high enough for CFD, but better than a low-poly model pulled off 3-view drawings.

I may blow a circuit with a body swap on the old tdi..

What fuselages could you choose from? The was a garage in Cedar Flat that had a Beech twin-engine plane he wanted to put onto the road. The result would have been a big long frunk with a little passenger compartment.

After having seen some people chop up a beetle to build small campers...

Some are better than others. Here's one that's half-way to the Lil Bugger rolling outhouse:


The most aerodynamic would be the BGW van conversion:



Alls it needs is a separation edge; and something the New Beetle shares -- the rear fenders. The best practice seems to be a ducktail on each fender:


https://external-content.duckduckgo....017&ipo=images

Ignore the widebody flares. This is a RWB/ Robert Design collaboration.

[razordave]

I'm not sure what aircraft is available yet. I will see the estate for the first time tomorrow 0900.

I think my workspace manager already axed the aircraft body swap unfortunately. Depending upon what kind of deal I can make I'll keep everyone posted.

I will definitely be visiting the duck tail on rear fenders.

I removed the rear muffler on the beetle. Between the rear seat and muffler we should be 100 lbs lighter. The catalytic converter has over 200k on it so it is probably time to replace it with a high flow, lightweight option as well.

I was amazed at how smooth the underside of this car is. Was considering a rear diffuser but it will have to be tied into the after body.

[freebeard]

I'm not sure what aircraft is available yet. I will see the estate for the first time tomorrow 0900.

I'm hoping there is a Hughes_OH-6_Cayuse. Good luck.

[razordave]

Although that Hughes would have been a great find, what I encountered was ultra light experimental with no real body.

There was a promising looking aluminum boat, but I've already been looking at a fiberglass kayak, an aluminum canoe and a 14' aluminum fishing boat for possible boat tail material.

Good news, I was able to score a retired 55 mph interstate sign from which I will construct a skidplate to replace the missing front undertray on the beetle.

I was considering a prefabricated piece from ebay, man am I glad I didn't spend $179+ shipping.

[razordave]

I tore the truck cap down and began building a 5ft boattail. Late into the night with a stripped nut driver, I decided to call it.

I did slap the old 3.0 version back on and seal the leading edge. I have driven 100+ miles without it, so I'll report when I fuel up.

On the freeway 80mph avg I was doing 33mpg.
I did about 280 miles around 24 with the unsealed spoiler.

Edit: 27.4 mpg with no spoiler but I also deleted the muffler.

[razordave]

I will edit this post with some photos in the day light. Edit missed daylight but hopefully you get the idea.

I hitch mounted a Honda civic trunk to use as a base for a Bonneville style spoiler. I think it's 4 inches too wide and doesn't fit the contour of the rear window perfectly but duct tape makes a good temporary seal.

I made lower end plates and added a 1.5-2" duck tape duck Bill spoiler.

I wound it up to 95mph coming out of Mexico and the duck tape laid down so I may remake that out of lawn edging or maybe just leave it alone as a clean separation edge.

Most of my previous attempts failed because I was trying to walk a line to be able to utilize my hatch.

Once I've finished this section I should be able to remove the hitch mount and open the hatch.

I've done a terrible job at tracking my economy other than a 46 mile highway jaunt to try to buy a salvage airplane. That run was 33.5 mpg

I found a piece of exhaust that I had made for a previous project that never made it on. Should work to mount my "new catalytic converter." With 212k+ on what I presume to be the original, I believe it's time.

The planes I found are Aerostar 601p 700 etc. The owner buys salvage and restores some and has a few that are pretty well stripped (read hopefully in my price range. ) they are 6 seaters with a decent cargo/baggage hold. I'm very excited to try to make a deal but I think the first one I buy will become a camper trailer. The whole convert your daily driver into a road legal airplane became pretty daunting while ogling plane carcasses.

[freebeard]

https://en.wikipedia.org/wiki/Piper_Aerostar

That's the one the guy in Cedar Flat had (it's gone now). The fineness ratio is good for laminar flow, but don't you think the nose is impractical?

[razordave]

I do think the nose is a no go, I was considering utilizing the windscreen and forward of the car. Lights, wiring bumper vin etc. I believe that would maybe let me slide past a cop every so often.

It's funny but I can imagine being towed because the windshield is not dot approved. I know, I know. It's good enough for an airplane but I kid you not I've had bigger problems from what I thought would be a lesser issue.

Link to the YouTube video with attached airplane car
https://youtu.be/mUKDowTrlp4?si=HbVrLMBQ9kBmdHP5