smudgersmb
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 posted on 23/12/04 at 08:48 PM |
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I'm Flying
When I reach 60mph I can feel the front of the car "lift" and it gets very "light" and then when I reach 90mph I can actually
see the front of the car rise up in the air. As you can imagine this is quite interesting. So how do I go about stopping this? Is it because the front
is very light? The shape of the front wings? The suspension set up? Or all of the above?
Smudger
Tree Rats - I hate em!
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subk2002
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| posted on 23/12/04 at 09:50 PM |
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stick a slab in the front  
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kb58
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| posted on 23/12/04 at 10:13 PM |
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Give it a bit less elevator... you are building a plane, right?
Seriously, what are you building? then maybe we can held. If it's a Locost sort of car, get rid of any big, body mounted fenders at the
front.
What are your front suspension settings? Toe? Camber? Caster?
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
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ReMan
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| posted on 23/12/04 at 10:19 PM |
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Notorious for lift
 
Rescued attachment 21434.jpg
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ReMan
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| posted on 23/12/04 at 10:21 PM |
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Sorry could`nt resist , is it one of these then?
Even BIGGER wings
[Edited on 23/12/04 by ReMan]
 
Rescued attachment mosq.jpg
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sgraber
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| posted on 23/12/04 at 10:25 PM |
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He's building a Mosquito.
Mini powered middy. I had no idea that it would do 90!
You'll have to attach some gurney strips along the leading edge to break up the lift?
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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Hellfire
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| posted on 23/12/04 at 11:12 PM |
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OMFG
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Cita
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| posted on 24/12/04 at 09:11 PM |
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When you are talking about that green car....it's probably a combination of a very light loaded front and very effective (in terms of lift! )
front wings.
It looks as those mud guards are shaped according the coordinates of a high lift glider wing airfoil and even the angle of attack looks good
Get rid of those front wings or one day they will brake off or glue some strips over the leading edge to disturbe airflow if you wonna keep them.
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Peteff
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| posted on 24/12/04 at 09:27 PM |
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A couple of these should fix it.
Put them in the front between the wheels. 
 
Rescued attachment solnmanh0068-7.jpg
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Cita
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| posted on 24/12/04 at 10:09 PM |
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smudgersmb
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| posted on 30/12/04 at 11:30 AM |
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The Mosquito is my daily driver. I use it to - from work 5 days a week. It does have "gull-wing" doors as well. Handy in winter (ish).
Their is no room in the front for bags of sand etc as fuel tank takes up quite a bit of room, hence no front rad. I was looking at changeing the front
wings to cycle wings (I sell Carbon Fibre cycle wings). I was looking at the totally flat underneath as a possible lift problem as well. I am looking
into getting different dampers and lower them as well, but it is still a problem with lift at speed.
For the interested. Got clocked at 108mph on a "private" road (M6) so it can shift
As for castor/camber Hmmm. Will be fitting HD Tie Bars all round and 1.5 Neg Camber Bottom arms up front. But what caster/camber for the rear?
Would a underbody diffuser work? If so what shape and how to fit?
Smudger
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JoelP
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| posted on 30/12/04 at 01:29 PM |
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preventing air going under the car, or facilitating its exit at the rear (like the old f1 cars with the hugh fans!) will create low pressure under the
car. this will help it stick to the road. in the absence of a convenient wind tunnel, i would suggest trial and error. Ditch the front wings, make a
small dam to go under the front, and also see what weight could be moved forward (battery?).
how does the car handle? does it feel like the weight balance is too far back?
Beware! Bourettes is binfectious.
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sgraber
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| posted on 30/12/04 at 04:54 PM |
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Make sure to "rake" the chassis so that the front end is lower than the back. That'll make your flat undertray work like a diffuser.
If it's totally flat at rest, then those big wing fenders will be lifting the front at speed, which will then rake the car the wrong direction
which will inevitably cause it to lift even more... and so on and so forth. Of course adding the air dam at the front will help this condition
considerably.
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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krlthms
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| posted on 30/12/04 at 06:49 PM |
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quote:
Originally posted by smudgersmb
,
hence no front rad.
Smudger
Looking at the shape of the front grille, I suggest that you are building an area of high pressure UNDER the bonnet at speed, because there is an air
inlet (grille) shaped to collect air (upper lip), and no outlet. Since you say there is no rad at the front, you should try blocking the gille (e.g.,
plywood on the inside), and maybe installing a NACA duct or louvers on top of the bonnet facing backwords to permit air exit.
Installing cycle wings is a no-brainer; the car looks much nicer with them.
Cheers
KT
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smudgersmb
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| posted on 30/12/04 at 07:56 PM |
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The grill at the front is their for "show" and does not have any holes in it at all.
Their is no room at the front for anything to be moved. Its all taken up by Fuel Tank, Fuel Pump and horn.
What type of Air Dam? What style? How to make one?
Car feels VERY light when driving, this is due to the A Series being in the back and the previous owners never having set the car up properly.
I am going for 90mph (3.9 Final Drive) but it still needs to be contrable at that speed.
I remember the AUDI going flying at Le Mans not so long ago and dont want the same thing happening (on a smaller scale) to me
Smudger
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smudgersmb
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| posted on 30/12/04 at 07:58 PM |
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The problem with cycle wings is:
1. Where to mount them?
2. I can't make the brackets so who can?
3. I sell CF cycle wings so who wants some
Smudger
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Northy
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| posted on 30/12/04 at 08:03 PM |
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No the real question is:
Whats your best price for a poor man?
Graham
Website under construction. Help greatfully received as I don't really know what I'm doing!
"If a man says something in the woods and there are no women there, is he still wrong?"
Built 2L 8 Valve Vx Powered Avon
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Cita
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| posted on 30/12/04 at 08:14 PM |
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quote:
Originally posted by smudgersmb
The problem with cycle wings is:
1. Where to mount them? Obviously above the wheel
2. I can't make the brackets.Why not?
3. I sell CF cycle wings so who wants some?Are they delivered with brackets?
Smudger
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smudgersmb
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| posted on 31/12/04 at 03:13 PM |
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Cycle wings in CF showing weave (poor pic)
 
Rescued attachment Cycle Wing.JPG
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Cita
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| posted on 31/12/04 at 05:04 PM |
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Very nice looking wings indeed!
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Northy
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| posted on 31/12/04 at 05:29 PM |
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Best price for a poor man?
Graham
Website under construction. Help greatfully received as I don't really know what I'm doing!
"If a man says something in the woods and there are no women there, is he still wrong?"
Built 2L 8 Valve Vx Powered Avon
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Cita
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| posted on 31/12/04 at 05:41 PM |
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Smudger
Looking at the shape of the front grille, I suggest that you are building an area of high pressure UNDER the bonnet at speed, because there is an air
inlet (grille) shaped to collect air (upper lip), and no outlet. Since you say there is no rad at the front, you should try blocking the gille (e.g.,
plywood on the inside), and maybe installing a NACA duct or louvers on top of the bonnet facing backwords to permit air exit.
Installing cycle wings is a no-brainer; the car looks much nicer with them.
Cheers
KT
You can build up pressure as high as you want under that bonnet but that aint gonna give any lift me thinks.
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