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Old 05-12-2006, 12:56 AM   #31
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Originally Posted by scott_g
Dale, have you put any of your bodies into a wind tunnel? or attempted to measure downforce? That would be fascinating data - what front and rear downforce is generated at what speeds.


In offroad (EP) A few years ago we were playing with mounting wings directly onto rear hubs so that any downforce wasn't interfering with suspension. The team we were running for at the time said they had tested and found that offroad wings generated no downforce, just what they called "stabilising drag". We put out experimental wings away in the cupboard and went back to suspension tuning!
Yup , my friend built a wind tunnel last year , he had tuned to 38 miles per hour..with a scale in the tunnel every body we tested made the most down force @ 12 miles per hour..from 12 to 38 MPH all bodies made lift, the body acts like a parachute the body was pulling the car off the scale ..52ounces turned into about 30 on the wind tunnel scale..The only way a body wont make lift is to have a under tray and fill in the wheel wells....now for the offroad wing thing it is a must to have a wing in off road the car wont fly flat over big jumps and will spin out @ the end of a very fast straight..Ask Pudge if his car works with out a wing..Duh..
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Old 05-12-2006, 02:03 AM   #32
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The lambo shells... (gallardo, murcielago) have AMAZING turn in... the most steering of ANY shell i've ever treid. So incredibly unbalanced... i suppose it could work with an insanely illegal sized rear wing but wow..

no rear downforce at all (without wing of course..)... what can you expect from a wedge right?

Kinda fun to bash with though...
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Old 05-12-2006, 05:49 AM   #33
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Quote:
Originally Posted by AngryAsian
The lambo shells... (gallardo, murcielago) have AMAZING turn in... the most steering of ANY shell i've ever treid. So incredibly unbalanced... i suppose it could work with an insanely illegal sized rear wing but wow..

no rear downforce at all (without wing of course..)... what can you expect from a wedge right?

Kinda fun to bash with though...
actually I have one murcielago from HPI and with the optional plastic wing from hpi as well it works really well. Although I'm talking about 23T motors.... not sure what could happen with a mod...
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Old 05-12-2006, 07:20 AM   #34
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Originally Posted by Soviet
As of now, you're crossing over into the Voodoo and snakeoil side of R/C touring, a place where people SWEAR up and down that they can "feel the difference" between a Mazda 6 and a Nemesis.
I can tell a huge difference,Not only in "feel" but lap times as well..
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Old 05-12-2006, 07:59 AM   #35
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I'd assume it COULD work quite well with a large wing! A la HPI kit..
I suppose the only downside is the high drag. It still can't compete with the lower profile racing shells. The racing shells have several key features that do improve aero performance. Small sills on the sides of the bonnet, a sharply tapered roof, a setback windscreen - again with sills.

A sharp downward sweep to the c pillar and a flat trunk for the most effective use of the rear wing.

Then again, who am i to talk. If my laps were more consistent then i'd do much better than any "Aero" shell could get me up the time charts! LoL
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Old 05-12-2006, 08:49 AM   #36
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If all goes to plan I intend to do a project on Aerodynamics for my Physics degree final.

I was originally thinking of focussing on 1:12th scale bodies (can't remember how big our wind tunnel is), but even those are amazingly complicated with effects coming from the front splittler, front arches, centre section, rear tail, diffusers etc etc. I think I may instead experiment on wings on Touring Cars.

You have to remember with Aero on our size cars that the centre of pressure is also affected - this can have more of an effect that the actual downforce of the shell.

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Old 05-12-2006, 03:07 PM   #37
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scott_g:
No, I do not currently windtunnel test Protoform bodies. The reasons are many - so I won't go into it. In 1993 NPTI Nissan Racing in Vista CA windtunnel tested some of my on-road bodies to cross reference data they had gathered for the Nissan GTP-90 racing program. (the car that Geoff Brabham was using to dominate the IMSA GTP series at that time) Ironically, I happened to be there on fall of 1993 and saw the unveiling of the all new Nissan P35 racer. Wow, did my camera and tape measure come out on a hurry. One of those rare "right place/right time" type of deals. One week later Nissan pulled the plug on the whole race program and laid off all 315 race shop employees. The "real" Nissan P35 that I drooled all over never actually raced. Only 9 months later the Protoform 1/10th Nissan P35 was used my Masami to win the IFMAR Worlds event in Germany - and in so doing put my floundering new company on the map. The Protoform 1/12th scale P35 won every imaginable event in the world as well - for many years - until ROAR legalized 1/12th scale slot car bodies.(I know I'm off topic - but I also know that there's some trivia buffs like me out there as well. sorry guys)
Anyway, I may end up with a small scale windtunnel yet. NASCAR driver Todd Bodine (currently the points leader in the CraftsmanTruck division) has built one and wants me to get involved at some level. We're both kinda stretched for time right now - but who knows.

AngryAsian:
I like your assessment in post #27 regarding wing width etc. I agree 100%

C_O_jones:
You're too funny.

Bobby J:
Very interesting findings. Very believable. I'd love to know more if at all possible. Send me a pm if you're even remotely interested. I'll make it worth your while if I can. Thanks in advance.

Dale - Protoform
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Old 05-12-2006, 03:20 PM   #38
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Quote:
Originally Posted by DaleEpp
The Protoform 1/12th scale P35 won every imaginable event in the world as well - for many years - until ROAR legalized 1/12th scale slot car bodies

So maybe us Brits weren't old men in anoraks after all and could see what would happen
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Old 05-12-2006, 03:34 PM   #39
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Anyone have any success with the Protoform Molded wings?

It would seem to me that a stiffer wing would be more stable than the thinner ones that come with the body. Not to mention its shape is more consistent.
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Old 05-12-2006, 03:39 PM   #40
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The car is 1/10th the size of a real racer, but they do around 30 - 40 mph. Now if you times that by 10 it's 400mph/ 643kph. I have yet to see a real car do that speed on a race track. I'd rather drive a car with a good rear wing than without one thats for sure. Even a 2mm change in the rear will make a huge difference at a scale speed of 640 kph.
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Old 05-12-2006, 03:53 PM   #41
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Quote:
Originally Posted by BimmerDriver
I believe aero is important in all scales. Back in my slot car days I had a 1/24 scale Cox Chaparral (circa 1967) and a Cox Ford GT-40. I switched bodies on chassis and no matter what I did, the Chaparral was never as fast... never as good handling... as the GT-40. Being a die-hard Chevy fan, this was a hard pill to swallow.
Yeah I drive one of those "bimmers" 2005 325 5 speed. not bad!!
I too had a Cox Chaparral, and got it to work with a much larger spoiler attached and extended from the original one. There used to be a large slot car track in Ladera Heights area of Los Angeles. I believe it is now a 99 Cent store, I think. '67 was a long time ago.

after I transitioned into rc we raced pan cars at the Ranch pit shop. I remember somebody offered an air foil rear wing. It had the cross section of an upside down airplane wing. I wish I had something like that now. the wing shape would give downforce without a lot of drag because you can mount it level and it would still give you down force because of the inverse lift with the air flowing faster under the wing.

What if someone release a 1/10th Chaparral body with a inverse wing mounted on it? Oh well I'm day dreaming...
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Old 05-12-2006, 04:08 PM   #42
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Quote:
Originally Posted by Bobby J
Yup , my friend built a wind tunnel last year , he had tuned to 38 miles per hour..with a scale in the tunnel every body we tested made the most down force @ 12 miles per hour..from 12 to 38 MPH all bodies made lift, the body acts like a parachute the body was pulling the car off the scale ..52ounces turned into about 30 on the wind tunnel scale..The only way a body wont make lift is to have a under tray and fill in the wheel wells....now for the offroad wing thing it is a must to have a wing in off road the car wont fly flat over big jumps and will spin out @ the end of a very fast straight..Ask Pudge if his car works with out a wing..Duh..
While I find the results interesting, I'm just not sure.
On my previous car, Mission, I had an HPI Alfa shell which handled OK until during a race when the wing fell off. All of a sudden it woudn't go around corners at all. I had to back off round the high speed sweeper, it was a bit better around the slower corners (as you would probably expect).

I simply say this, if the body isn't utterly crap to begin with (speaking aerodynamicaly), then a wing is a necessity.
Having said that I have seen the odd car have the wing come off and it didn't seem to slow the car much at all.

Strange

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Old 05-12-2006, 05:06 PM   #43
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Dale you got a PM...
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Old 05-12-2006, 05:58 PM   #44
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Quote:
Originally Posted by wcalaker
Anyone have any success with the Protoform Molded wings?

It would seem to me that a stiffer wing would be more stable than the thinner ones that come with the body. Not to mention its shape is more consistent.
Thats what I tested.
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Old 05-12-2006, 06:05 PM   #45
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I think what im going to do is, cut down the 200mm wing to roar legal specs. Then I will add lexan to the top to make almost a NASCAR style wing on top of it. Hopefuly I then can adjust downforce by bending it to different angles. Maybe I will also make a piece and angle it to push air up to the wing. This will prevent air from going between the wing and the trunk of the body.
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