Lotus 7/Locost Aero Rebody

[MetroMPG]

Bristols were 1-2-3 in the 2 liter class at Le Mans '54 with that coupe design (shown on page 1 of this topic) so it couldn't have been a complete turkey

Just less of a turkey, speaking relatively!

[JackMcCornack]

Originally Posted by MetroMPG

Just less of a turkey, speaking relatively!

That's fair, it was competing with its peers of 1954, but I think the principles of automobile aerodynamic drag reduction were well understood by then. I was being a smart alec with my "I have my Hucho and Bristol didn't" remark, and though Bristol had only been in the car biz a few years, and though it was an era when the practical lessons of 50 years of aerodynamic experience could be boiled down to two semesters, the Bristol 450 Coupe had some interesting innovations. The fins, which were assumed to be stabilizers, were more likely (IMHO) there to reduce vortexes spilling over the sides and into the wake of the roof section--that's what they look like to me here in 2009 and the assumptions of mid-50s auto journalists not withstanding...well, in the mid-60s Jim Hall let the industry assume he was bleeding the Chaparral's underbody air up through holes in the wheelwells in order to keep the tires cool, I'll bet the Bristol folks knew how to keep a secret too.

If we crank up the time machine ahead ten years, we get the 1964 Cobra Coupe, also a successful endurance racer and another source of inspiration...but to me it looks too modern, too fast, and I think an econocar version would seem like a parody rather than an homage (and I wouldn't do it anyway because like the Bristol, that body would be too expensive). Still, it would fit the Lotus 7 layout and if you got rid of the spoiler it would be pretty slippery.

[hypermiler01]

[hypermiler01]

Originally Posted by JackMcCornack

But I don't, so I'm looking for as few compound curves as possible, in hopes the bulk of it can be made from sheet materials.

My Geo body will cost less than $1000 even though I am using epoxy resin. Curves are easy with a good skeleton underneath.

[JackMcCornack]

Hi hypermiler01, that's an Atlantic, right? One of the many zooty between-the-wars cars that would have less drag going backward than forward. I love it but OMG with a Z, it would be costly to reproduce!

I'm going to take another look at the Bugatti Tank shown earlier (the blue car with the flat sides and lots of louvers).

PS--Just saw your Metro Streamliner! That is way cool! Do you have a topic on building it? Is it fwd? Tell us more!
(If it doesn't have its own topic yet, it sure deserves one.)

[hypermiler01]

Originally Posted by JackMcCornack

I'm going to take another look at the Bugatti Tank shown earlier (the blue car with the flat sides and lots of louvers).

About the Jaguar C-Type long-tail:
"Low and rounded at the nose, low and pointed at the tail, it not only looked like an airplane wing (in cross-section) but acted like one. The cars wanted to fly. In fact, their rear ends lifted so much that load on the rear tires was reduced by a good quarter, and the drivers came back to the pits ashen-faced to report evil instability. The older body had shown a tendency to lift a bit, but nothing like this."

Porsche and Ferrari also had similar problems with long pointy tails that were too low.

Originally Posted by JackMcCornack

PS--Just saw your Metro Streamliner! That is way cool! Do you have a topic on building it? Is it fwd? Tell us more!
(If it doesn't have its own topic yet, it sure deserves one.)

It does have a thread here.

[lunarhighway]

seems like flipping that tail upside down might work wonders on that car, could turn all that lift into downforce

[Bicycle Bob]

IIRC there was a year or so when options for downforce in F1 were very restricted, and Lotus found that a really smooth, well shaped belly pan could speed up airflow under the car to give a venturi effect. John Cobb's Railton Special, which held the LSR for decades, is a good example of a symmetrical airfoil shape modified to allow for interference from the ground. Designs can be tuned by raising the back end to increase suction to the venturi section and bring the low-pressure zone from the rear underneath, but a major rake would want side skirts to help maintain the pattern.

[Arragonis]

There are a few streamlined racers here (8W - When? - Forties & fifties German F2, F Libre and sportscar racing) including apparently the worlds fastest unsupercharged car.

Also the Piper (yellow on here Marenda Lindsey Ltd) could be useful ?

[botsapper]

Another source for inspiration & study. Maybe a little bit more that what you have in mind (budget) but maybe you could source out their cool compound curve wind screen.

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