Building a 100mpg consumer vehicle

[NeilBlanchard]

60" x 24" = 1,440 sq in = 10 sq ft
42" x 35" = 1,470 sq in = 10.20833 sq ft

Obviously the greenhouse has angled sides so that takes away say 1/3rd of the area(?) so that leaves 6.8 sq ft for the green house.

Edit: Question: what is the height of the greenhouse *above* the hood? As I think about this more, I think the 42" height has to be the total height? If so, then the height is actually 18" or so? then the greenhouse is a lot smaller at 18" x 35" - 33% = 422.1 sq in = 2.93 sq ft.**

You have to also add the exposed areas of all three wheels -- say 6" x 4" for each? That is 24 sq in x 3 = 72 sq in = 0.5 sq ft.

So the very rough estimate of frontal area is 10 + 6.8 + 0.5 = 17.3 sq ft.
Edit: 10 + 2.93 + 0.5 = 13.43 sq ft**

If I could trace a polyline outline of the entire car, it would be a lot more accurate. A long telephoto lens limits the optical distortions making it the most accurate possible short of a laser outline or a 3D scan.

[Grant-53]

What we have here is what I call the 'ugly baby syndrome', if someone says my baby is ugly I am going to take offense. There is sometimes friction between those who studied mechanics at college and those who studied in the garage or pole barn. The late Mark Donohue did both, Smokey Yunick was a self taught genius with a number of patents. Let's give each other a little leeway on personal taste.

Until a set of coast down tests are done we are making educated gueses as to the CdA. Put me in the pool for a Cd of 0.38 and area of 13 sq. ft

[drmiller100]

Neil,

the greenhouse is BEHIND the front fenders.

the very rear of the car is 10 inches wide and 20 inches tall.
the areas behind the fenders are 10 inches wide and 22 inches tall.

still like the .40 number?

[skyking]

did you drive it?

[drmiller100]

sounds stupid, but i need an idle control solenoid.

and the state inspectors want me to have lights on it before they will issue a vin

stupid stuff

[sgtlethargic]

Originally Posted by pete c

Don't let the door hit you in the arse, doug.

What a tempermental doosh. I've been pretty damn complimentary overall of his work, as have many others and we continue to get the same treatment.

And yes, that scoop isn't just silly. It looks like arse. It screws up what is otherwise a very nice looking rear half of the car.

My apologies to all those out there that I may have deprived of doug's car design brilliance.

Go comment on Youtube instead, please.

[pete c]

Originally Posted by Grant-53

What we have here is what I call the 'ugly baby syndrome', if someone says my baby is ugly I am going to take offense. There is sometimes friction between those who studied mechanics at college and those who studied in the garage or pole barn. The late Mark Donohue did both, Smokey Yunick was a self taught genius with a number of patents. Let's give each other a little leeway on personal taste.

Until a set of coast down tests are done we are making educated gueses as to the CdA. Put me in the pool for a Cd of 0.38 and area of 13 sq. ft

Trying to pull a CdA number out of thin air on this one is tough. On the one hand, you have a very tiddy rear end that should help quite a bit. On the other hand, you have a front clip that kind of ends abruptly. So, unlike traditionally shaped cars where we have a long history of figures to use to pull CD numbers out of our collective arse, this one is gonna take actual tests.

[pete c]

Originally Posted by sgtlethargic

Go comment on Youtube instead, please.

I don't come here looking to flame people, sarge. Plenty of other places on the interwebs for that. But, as I've already said here, quite a few pages back on this very thread, what are you supposed to do to someone who continually belittles your posts?

I called his scoop silly.... after he said himself that he wasn't happy with it. I was otherwise quite complimentary and encouraging.

[Frank Lee]

There is darn little going for his shape aerodynamically besides the small frontal area and small trailing wake area at the rear. I think the entire sides from the front fenders on back are in a sea of turbulence because of the design of the front fenders. It probably makes no difference to aero if that scoop is there or not. It is entirely possible that a pickup has a better Cd.

This design actually has a good shot at good flow all along to the rear, such that the small trailing wake at the rear is the only wake. The rise on the bottom is probably too steep though.

[Frank Lee]

Originally Posted by drmiller100

Neil,

the greenhouse is BEHIND the front fenders.

the very rear of the car is 10 inches wide and 20 inches tall.
the areas behind the fenders are 10 inches wide and 22 inches tall.

still like the .40 number?

The greenhouse is ALSO ABOVE the fenders, as it is on practically everything. Are we still having trouble with the concept of frontal area?

Imagine a cone, pointy end leading into the flow. The area at the front is almost nothing; the area at the very very rear is the entirety of the "frontal area" even though it's at the rear. Frontal area is the size of the hole punched through the air; forget about if that occurs at the front or not. More intuitive terminology for it could be "maximum cross sectional area with consideration for variations from front to rear" (because the max cross-sectional slice of the typical road vehicle body wouldn't have the wheels and tires represented) or "The Wile E. Coyote silhouette through the fake paper road and landscape" but it is what it is.