Middy Tim
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| posted on 11/1/07 at 01:56 AM |
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Locost Aerodynamics... or lack thereof
These cars are infamous for their brick-like aerodynamcs... has anyone gone attempted to fix that problem? I was thinking something along the lines of
this:
- Duct radiator inlet and exhaust (vent out of hood... I'm planning a middy)
- Flat bottom with rear diffuser
- good aeroscreen (no near-vertical windshield)
- Inboard shocks with pushrods
Anyone have any input? Would this help at all or would it all be for the wind (no pun intended  ) ?
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PAUL FISHER
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| posted on 11/1/07 at 02:06 AM |
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Do you mean something like this.jpg)
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PAUL FISHER
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| posted on 11/1/07 at 02:07 AM |
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or this.jpg)
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PAUL FISHER
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| posted on 11/1/07 at 02:08 AM |
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or this more a road going version.jpg)
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Middy Tim
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| posted on 11/1/07 at 02:08 AM |
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Wow, those are pretty extreme. The second one looks more like a Morgan than a Lotus.
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PAUL FISHER
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| posted on 11/1/07 at 02:17 AM |
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A lot of the "locost" kits are going inboard suspension now as well MNR sportscars,the new MK Indy that I am building has inboard,and not
so locost but the original 7 the caterham csr 260 has inboard suspension,I supose you can make a seven a lot more les brick like,but then as the
pictures above they then become less like a true 7
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PAUL FISHER
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| posted on 11/1/07 at 02:21 AM |
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quote:
Originally posted by Middy Tim
Wow, those are pretty extreme. The second one looks more like a Morgan than a Lotus.
I agree,the top one is a westfield,pictured back in 1990 I belive,if I recal correctly did over a 170mph,the other two are donkervorts.
[Edited on 19/05/04 by PAUL FISHER]
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PAUL FISHER
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| posted on 11/1/07 at 02:31 AM |
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This is the MK inboard.jpg)
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PAUL FISHER
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| posted on 11/1/07 at 02:32 AM |
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and the csr,high cost compared to locost.jpg)
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macnab
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| posted on 11/1/07 at 08:24 AM |
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Wow that blue & red car is truly awesome!
just love the style though the doors a tad small!
[Edited on 11/1/07 by macnab]
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Rob Palin
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| posted on 11/1/07 at 09:13 AM |
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A while ago we did a more aerodynamic 7. It wasn't just the drag that needed attention as the standard-spec car has over 40kg of lift at the
front at 100mph.
Moving the suspension inboard had not as much effect as you would have thought, since the widest part of the car is still the rear and pretty much
anything you do to tidy up the flow at the front just means that the air is in better condition when it smacks into the rear arches.
The standard windscreen is horrendous so an aeroscreen is a fair improvement.
Getting a diffuser to work is very tricky, again because of the backward shape of the car (it's like an aerofoil in reverse with the ends
chopped off). It's important to control the flow inwards from the side edges of the car - which unfortunately means having endplates /
sideskirts much of the way along the underside. It's also important not to go too steep with the diffuser itself and have it made from one bent
piece of ally or whatever, rather than two straights ones which meet at the apex - any mismatch or gap here will render the whole thing useless.
The most critical areas for lift are the front wheelarches. You can reduce lift by nearly 70% just by treating them properly. Have long ones that
cover from at least 3 o'clock to 9 o'clock (viewing the wheel from the side as a clock face) and have them as close to the tyre as you
dare. Cutting louvres in them also wirks a treat but you'll have to put some wire mesh/gauze in them to stop stones etc coming out. A wire
gauze would limit dirt/water whilst still retaining part of the aero benefit.
Hope this helps.
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macnab
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| posted on 11/1/07 at 09:40 AM |
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all very usefull stuff
there's an idea, just make the front wings out of mesh...
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BenB
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| posted on 11/1/07 at 10:48 AM |
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The importance of having a roof and windows etc for aerodynamics is also often underestimated.
Each to their own but personally I think trying to make a Se7en aerodynamic is missing the point. They have truly brick-like drag coefficients. Even
fairly substantial % improvements in drag are going to have small effects due to the massively disadvantaged starting point.
You'd need to rake back the screen, put a roof and windows on, get rid of the Jaws like opening at the front, cover the wheels completely, get
rid of the sticky-outy headlights
Ooh hang on, someones done it
(okay it needs a roof!!!)
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macnab
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| posted on 11/1/07 at 11:46 AM |
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oh but look at those headlights missing the plastic windows...
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Phil. S
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| posted on 11/1/07 at 11:59 AM |
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You can buy vented wings like the ones I have on my car, which will help.
 
Description
If you put an aeroscreen on, put half doors on also, as these will help smooth the airflow down the side. I got mine from Fluke Motorsport.
 
Description
[Edited on 11/1/07 by Phil. S]
"The unexamined life is not worth living" (Socrates)
"The unlived life is not worth examining" (Kopp)
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BenB
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| posted on 11/1/07 at 12:05 PM |
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Blimey. Fluke sure aren't Locost!!! How much for a rear diffuser!!! Shamoan!
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Confused but excited.
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| posted on 11/1/07 at 12:08 PM |
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quote:
Originally posted by PAUL FISHER
quote:
Originally posted by Middy Tim
Wow, those are pretty extreme. The second one looks more like a Morgan than a Lotus.
I agree,the top one is a westfield,pictured back in 1990 I belive,if I recal correctly did over a 170mph,the other two are donkervorts.
[Edited on 19/05/04 by PAUL FISHER]
170mph? Sh1t, that's fast for a snow plough!
Tell them about the bent treacle edges!
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Rob Palin
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| posted on 11/1/07 at 12:09 PM |
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Did you get the nosecone from Fluke as well? I'm keen to get one of those with a lower intake aperture. Does yours fit a book chassis?
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macnab
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| posted on 11/1/07 at 12:13 PM |
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I think I'm going for the mesh vents in the wings, after the SVA test off course.
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Phil. S
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| posted on 11/1/07 at 12:27 PM |
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quote:
Originally posted by Rob Palin
Did you get the nosecone from Fluke as well? I'm keen to get one of those with a lower intake aperture. Does yours fit a book chassis?
The nose is standard Westfield. I don't know whether it will fit a book chassis.
"The unexamined life is not worth living" (Socrates)
"The unlived life is not worth examining" (Kopp)
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Phil. S
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| posted on 11/1/07 at 02:21 PM |
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Where'd my posts go???
[Edited to say:] They've reappeared and now I can't delete this one.
[Edited on 11/1/07 by Phil. S]
"The unexamined life is not worth living" (Socrates)
"The unlived life is not worth examining" (Kopp)
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macnab
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| posted on 11/1/07 at 02:24 PM |
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Ehem, whys the post at the top duplicated now?
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Rob Palin
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| posted on 11/1/07 at 02:30 PM |
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quote:
Originally posted by Phil. S
The nose is standard Westfield. I don't know whether it will fit a book chassis.
I thought i recognised that picture from the WSCC. One of the guys here is a Megabusa owner so i'll get some dimensions off him. Ta.
As an aside, the Fluke arches probably wouldn't need the louvres if they extended further forward around the tyre. There don't seem to be
many people selling long arches though - is because people think they don't look very pretty?
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DarrenW
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| posted on 11/1/07 at 03:11 PM |
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Wouldnt it be easier to compensate for the poor aerodynamics with a bit more power?
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Rob Palin
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| posted on 11/1/07 at 04:31 PM |
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Wasn't that Enzo Ferrari's opinion? "Only incompetent engine builders need worry about aerodynamics!".
Then someone pointed out that it can help you go round corners faster, too...
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