Date: Sat, 28 Jul 2007 16:15:00 -0700
Reply-To: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Subject: Re: Improving the "Package" with motors and Aero..
In-Reply-To: <001201c7d163$c679ff80$2219e442@dhanson>
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Don,
I *love* that you posted this !
I'm massively fascinated by these open road Nevada races.
Can't wait to study the site more.
Do they have a 'lame-slow brick' class ?
Once I read that one year was won outright by a 19 year old driving a
modified Camaro and he averaged 219 mph for the hundred mile run, or
whatever it was ! ! !
One of the most interesting things you mentioned was disconnected anti-sway
bars.
The navigator just has to hand his fate to the speed gods and the driver.
Imagine how it was in the 50's say, with worse roads, skinnier tires, and
cars with very few safety features - thinking Mille Meglia ala Moss &
Jenkins and the 300SL for example.
And I have read of people being killed in a Ferrari with inadequate tires in
the Nevada run too.
The forces involved at those speeds, should anything go wrong .....makes a
real mess.
The basics of aerodynamic improvements for road vehicles are well known -
small frontal area ( can't do much about that except keep it clean......side
mirror and junk on the outside.....and since you need at least one outside
mirror for legal reasons, best you can do there is make is small or very
aero ) ...
Smooth the bottom,
Reduce air inlets in the front,
Smooth the wheels as you mentioned,
Extend the tail, etc.
In vehicle design where the vehicle moves through a fluid medium like air or
water.....
Length is basically a 'free improvement.'
In sailboats, waterline length always results in more boat speed.
If a class size is limited to length by rules, they can maximize their gain
by making the bow nearly upright, for example. If there are no restricting
rules, then anything goes of course. Free reign for the designer.
In aircraft length is also a 'free gain' ......longer slender beats short
fat every time, more or less. Many requirements, some of them just matters
of pure practicality, have to be balanced out.
On vanagons .....well, I do have a plan for a curved roof section,
especially westy.
That front 'roof rack' ...I would love to see a wind tunnel view of this,
with a smoke trail showing the turbulence caused by that front roof rack
thing.......and the pretty rough and unattached flow all down the roof...
Yes, aerodynamically a vanagon is almost as bad as you could make it without
being silly.
I was looking at a Nissan Quest, van, and driving it - glides along
effortlessly at 80 mph at a nice 2,800 in top gear ....and QUIETLY too !
....non-flush side windows on the vanagon - BIG penalty, in noise and aero.
This box is a late 70's design, after all.
In the over all scheme of things.....crashworthiness, aerodynamics,
etc.....perhaps even emissions you can see that the basic vanagon layout and
shape ran its course and couldn't really work that well in modern terms.
But back to the Quest van - it's shaped like an egg. A pointy egg.. All
roundy, no sharp corners to catch cross winds, etc.
And the roof line .....
It's still rising at the point of the driver's head, to show you how
smoothed out and egg shaped that vehicle is.
A massive improvement over the abrupt 'sharp corner' at the front of the
vanagons' roof....
They had packaging in mind more there - a box or rectangle has the most
interior room for it's main exterior dimensions. That's why houses are
rectangular and not round - round ones are *really* refreshing and
interesting, but they have less effective room in them, less usable room
than the box or rectangle shape.
But....after that Quest van - wanted to graft the noise of it onto a
vanagon front. Or something.
Anyway....I sure appreciate your post and insights,
And I'll be checking out the Nevada racing thing !
Could you imagine, a 'fresh sheet of paper' vanagon chassis and body ,
factory made, and ALL the wiring, engine, trans, inferior bits, all of that
swaps over. You just buy the bare body /chassis ( they've made new
reproduction MGB bodies, for example ) and paint it the color you want,
install all your old van's guts ............it would not be hard to get up
to 40 % aero improvement just re-shaping it I don't think.
Scott
www.turbovans.com
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Don Hanson
Sent: Saturday, July 28, 2007 3:08 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Improving the "Package" with motors and Aero..
Aerodynamics are kinda the Achilles Heel of the Vanagon, aren't they?
There's a guy here in the Columbia River Gorge (windy place) who drives a
much modified newer Dodge van..Totally silly looking, but well done and it
probably get him a few mpg more. A big ole cow-catcher splitter on the
front with about 2" of ground clearance. Full skirts on the wheel wells
mounted with Dzus fasteners. A slick belly pan on the bottom, faired in
mirrors and best of all? All windsurfers have to carry a bunch of gear, so
this guy has a gutted out upright freezer mounted on the back on the right
side for all his sails and stuff and carries his boards upright on the left
side..all down out of the airflow...
The vanagon, I don't see much hope for big improvment in Aeros. Mine,
I've kept the top low and when I have a rack full of bikes, I mount it on
the rear hatch. Thats about all I can see to do easily. It's certainly
amazing how much drag even the smallest protrusion creates..stuff like cargo
boxes or spare wheels on top...
At Vanagon speeds, it's not too huge, but here in the Gorge, it's common
to see apparent wind speeds across your vanagon at well over 140mph. Going
down the interstate at 75mph and get hit with a 70mile an hour headwind
gust..There are pieces of RV all over the interstate to prove just
this...Shredded awnings, Air conditioner covers, the walls and roofs of
those rolling slum double wide modular homes...
Totally off topic: We used to compete our Porsche 928 in the Open Road
races over in Nevada.
http://www.openroadracing.com/
We ran in the Unlimited Class eventually, at speeds of up to 200mph. but at
one Pony Express Event we were in the Super Sport category, with a
'tech-speed' of just 165mph. Prior to the actual run at speed, they have a
practice session over a shorter section of highway, about 6 miles, where you
are allowed to test your equipment out and make sure all is right.
I had a different navigator onboard this time, who was unfamiliar with
the drill and forgot, during one of our 'passes' to raise his window...So as
we approached about 160mph, the gps balked and wouldn't go up...I am
checking all the gauges, the readouts, etc..wondering what happened to the
power,,then it flashes that the window is down...Well, at that speed, you
can't raise a window...it'll be blown right out...so we finished our run at
about 163..max..The return trip, we up all the windows and ran at an easy
175...and got chastised for exceeding our Tech Speed..
Running at those speeds demands all the mirrors off, tape on all the body
panel joints, un-hooked sway bars, an excellent alignment and some big
cojones, especially for the navigator, who has to read the route to the
driver and watch the mile markers blur past..
Don Hanson
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