Creative Idea's using Sheet metal..

[SlickE34]

I have a E34, 525i. I have been trying to brain storm idea's of what i could build for my car using sheet metal? I have full access for a Mechanical sheet metal shop, hand Tools, spot welder, cutting tables and AutoCad software Etc..

The only idea's i can think of is Air box's or some type of "Ram-Air" setup.

Feel free to share your creative idea's with me. Maybe i can start building something in the near future. :buttrock

[bmwwheelman]

I need a heat shield for my headers, lol, too bad you're so far away!

[AquilaBMW]

How extensive is the work you can do? I am in SFO

[BoldUlysses]

Some ideas:

- Engine splash pan / undertray
- Manifold flanges (for sale to aftermarket fabricators)
- Heat shields
- Big JDM triple-decker spoiler TYTE YO. :D

Do you have access to tubing and/or a mandrel bender? If so, the sky's the limit with exhaust and intake piping.

-Matt

[Russellc]

Some ideas:

- Engine splash pan / undertray
- Manifold flanges (for sale to aftermarket fabricators)
- Heat shields
- Big JDM triple-decker spoiler TYTE YO. :D

Do you have access to tubing and/or a mandrel bender? If so, the sky's the limit with exhaust and intake piping.

-Matt

There is a plastic splash pan available. I have one on my 95 525i. Sure helps keep water off belts.

[moroza]

Sunroof delete kit.
Flat underbody.
Diffusers/venturi tunnels/other aerodynamic pieces.

[5mall5nail5]

Coming soon to Pottsvegas, PA:

http://voytilla.com/gallery/albums/userpics/10003/normal_photo%2836%29.JPG

CNC plasma table. My friend is building it, he's almost done. I want to make an undertray for my car first :)

[SlickE34]

Some ideas:

- Engine splash pan / undertray
- Manifold flanges (for sale to aftermarket fabricators)
- Heat shields
- Big JDM triple-decker spoiler TYTE YO. :D

Do you have access to tubing and/or a mandrel bender? If so, the sky's the limit with exhaust and intake piping.

-Matt

I have thought about arrow dynamic pieces and Heat shields, I am going to "try" to design something and fabricate it. We have a couple bender's, Nothing great though, (1) Manual and (1) free standing up to 1". Our shop is most a full Mechanical Heating & Air conditioning/Sheet metal works. I am a Project Manager, I work in the Office, Just now putting 2 and 2 together LOL.

[bfp9]

Coming soon to Pottsvegas, PA:

http://voytilla.com/gallery/albums/userpics/10003/normal_photo%2836%29.JPG

CNC plasma table. My friend is building it, he's almost done. I want to make an undertray for my car first :)

excuse my ignorance, but what exactly can you make with this table? More specifically, what can you do with it that is beneficial for your car?

[SlickE34]

I did not post that picture, The other guy posted that, Going onto another topic. That picture has nothing to do with this thread, Other than the fact his buddy built that machine.

Cool looking machine though

[bfp9]

I did not post that picture, The other guy posted that, Going onto another topic. That picture has nothing to do with this thread, Other than the fact his buddy built that machine.

Cool looking machine though

hahaha i don't think he meant any harm. I wasn't calling you out on it either, i was asking Jon the question. Noffin to be worried bout!

[nismoracer65789]

fan shroud?

[Sam Son]

sunroof delete panel! Ill take one

[E34nication]

excuse my ignorance, but what exactly can you make with this table? More specifically, what can you do with it that is beneficial for your car?

That would be sweet... Old mechanic just got done building a full under tray for a customer's 993 race car... Aside from helping the overall aerodynamics of the car for cornering it also helped him gain 4-5mph on the straights... Think his lap times went down a second or two overall on searing (2:2x a lap track)

Edit: meant to quote 5mall and was referencing his underbody train.


sunroof delete panel! Ill take one

Home depot sells sheet metal in almost the perfect size... I think we cut off an inch or so from the back.

[Touhou]

1/4" thick skid plate
Considering our oil pans are $250 or so, it would be a good investment if you have a lowered e34.

[Sam Son]

Home depot sells sheet metal in almost the perfect size... I think we cut off an inch or so from the back.
Im trying to figure out what would be the best way of going about it...having the stock panel welded in place? or going to sheet metal I wanna ditch the sunroof because I never use it and I want to get ride of all that weight up top but I dont wanna lose any chassis ridgitiy...the stock panel might be stronger than sheet metal

1/4" thick skid plate
Considering our oil pans are $250 or so, it would be a good investment if you have a lowered e34.
Ive been longing for a skid plate for sometime...my oil pan is looking more and more like the lips on my style 5s

[E34nication]

Stock panel welded in for sure. If I can't sell my car and I end up having the fenders cut and widened I'm planning to have them do that at the same time.

[Russellc]

Sorry about this. I keep thinking 1950s buick front bumpers and 1959 caddy tail fins and fender skirts. :)

[sfgearhead]

Fender skirts! A set of curb feelers, ooo, smokin.

Shark fin?

No offense OP but you're going about this backwards. Your a solution looking for a problem. You need to find a problem, and then design a solution. Like a skid plate.

[Binjammin]

I did not post that picture, The other guy posted that, Going onto another topic. That picture has nothing to do with this thread, Other than the fact his buddy built that machine.

Cool looking machine though

You started a thread about what to do with sheet metal and creative ideas. That's a CNC plasma cutting table, for cutting parts out of sheet metal. It's only relevant if you take into account that it has everything to do with what you're talking about.

If I had access to a sheet metal shop? The hell with my cars, I'd make quick money building hvac and restaurant equipment. Until you have an english wheel or some other way of making compound curves, your sheet metal brake is only going to make sharp angles, like you said: good for boxes. Not something that's completely cheap from china all over ebay or anything.

Think bigger than cars, you'll make more money.

[5mall5nail5]

Guys the CNC plasma table will precision cut up to 1/2" of steel, maybe 5/8". Its cool - we are already trying to come up with ideas for what to make. Skid plate/front engine/subframe shroud would be hot. Fan shrouds are cake. Can actually cut custom stainless or aluminum washer tank bottle replacements that are all one piece that just need to be "folded" (braked) and welded. All kinds of cool stuff. He's hoping to cut his first piece this weekend I believe. I really want to make a skid plate and perhaps an under tray for the middle of the car though my exhaust is low. When I remove the rear fuel tank on the car I will have to make something to block off that space so as not to create a giant parachute out of my rear bumper. Not trying to derail, just excited to see sheet metal ideas and the coincidence that my friend is almost done his table.

[BoldUlysses]

Diffusers/venturi tunnels/other aerodynamic pieces.

I wonder how effective these would be without wind tunnel time? It's a neat idea but I'd always wonder whether I was doing more harm than good, aerodynamically. I'm just always suspicious of the real-world effectiveness of aero mods without hard numbers (even lower lap times or some such thing).

-Matt

[E34nication]

Guys the CNC plasma table will precision cut up to 1/2" of steel, maybe 5/8". Its cool - we are already trying to come up with ideas for what to make. Skid plate/front engine/subframe shroud would be hot. Fan shrouds are cake. Can actually cut custom stainless or aluminum washer tank bottle replacements that are all one piece that just need to be "folded" (braked) and welded. All kinds of cool stuff. He's hoping to cut his first piece this weekend I believe. I really want to make a skid plate and perhaps an under tray for the middle of the car though my exhaust is low. When I remove the rear fuel tank on the car I will have to make something to block off that space so as not to create a giant parachute out of my rear bumper. Not trying to derail, just excited to see sheet metal ideas and the coincidence that my friend is almost done his table.

Could always vent the rear bumper.

[5mall5nail5]

But then I'd need to get a honda badge ;)

Nah, i will do everything I can to not have to do that.

[BoldUlysses]

Where's the fuel tank going to go? Fuel cell in the trunk?

-Matt

[E34nication]

But then I'd need to get a honda badge ;)

Nah, i will do everything I can to not have to do that.

Same guy that did the underbody tray for the 993 race car did some work venting the rear bumper of a 986 race car... He cut out the license plate area, meshed it and ran the exhaust out if it... Getting rid of that parachute took the car from 125mph to 129mph on the back stretch of sebring...

[5mall5nail5]

Where's the fuel tank going to go? Fuel cell in the trunk?

-Matt

Yeah, cell in the trunk

[TGreene]

Interested in the skid plate and undercarriage covers/aerdynamic stuff, maybe an extra MPG?

[AquilaBMW]

I wonder how effective these would be without wind tunnel time? It's a neat idea but I'd always wonder whether I was doing more harm than good, aerodynamically. I'm just always suspicious of the real-world effectiveness of aero mods without hard numbers (even lower lap times or some such thing).

-Matt

If you are talking about the same kind of technology that was used in F1, then I wonder how practical it would be on primarily road cars.

The F1's cars back then not only had flat underbellys, but also had aerodynamics built into the bellys to generate additional down force. Basically, a wing surface of sorts was created underneath the car, using the same principles of "Lift" in planes, but in reverse. The designs created low pressure air "under" the car so it created negative lift or downforce.

The cars were insanely fast though - with speeds in excess of 150+ MPH to generate the needed airflow. Are we ever going to hit those speeds to warrant such aerodynamics? Kinda like a Honda Civic with a Full on Race Rear Spoiler perched high and yet is a DD running the city streets.

Am I off base here? :dunno

[BoldUlysses]

If you are talking about the same kind of technology that was used in F1, then I wonder how practical it would be on primarily road cars.

The F1's cars back then not only had flat underbellys, but also had aerodynamics built into the bellys to generate additional down force. Basically, a wing surface of sorts was created underneath the car, using the same principles of "Lift" in planes, but in reverse. The designs created low pressure air "under" the car so it created negative lift or downforce.

The cars were insanely fast though - with speeds in excess of 150+ MPH to generate the needed airflow. Are we ever going to hit those speeds to warrant such aerodynamics? Kinda like a Honda Civic with a Full on Race Rear Spoiler perched high and yet is a DD running the city streets.

Am I off base here? :dunno

Yeah, that's the technology in essence. The sidepods of early ground-effect F1 cars actually had airfoil cross-sections (evident if you removed the flat side panels), but after these were banned they fell back on totally flat underbodies, very low ride heights and side skirts to keep the low-pressure area trapped underneath the car.

Our cars obviously don't have sidepods that could be made into airfoils, so we're left with what we can do with the underbody and adding a front splitter and rear diffuser, in addition to whatever aero aids we could put up top (wings and the like).

My hesitation simply derives from our ignorance of the actual airflow patterns around our cars. For example, just because you cut a big hole in the front bumper doesn't necessarily mean more airflow to the radiator—it could be located in a big low-pressure area and give you no benefit at all. Same thing with extra aero—without a knowledge of how air flows around the car (i.e. wind tunnel time), it's all just groping in the dark, or trial and error (track time).

-Matt

[Binjammin]

If you are talking about the same kind of technology that was used in F1, then I wonder how practical it would be on primarily road cars.

The F1's cars back then not only had flat underbellys, but also had aerodynamics built into the bellys to generate additional down force. Basically, a wing surface of sorts was created underneath the car, using the same principles of "Lift" in planes, but in reverse. The designs created low pressure air "under" the car so it created negative lift or downforce.

The cars were insanely fast though - with speeds in excess of 150+ MPH to generate the needed airflow. Are we ever going to hit those speeds to warrant such aerodynamics? Kinda like a Honda Civic with a Full on Race Rear Spoiler perched high and yet is a DD running the city streets.

Am I off base here? :dunno


Read up on F1 "Fan cars"

[AquilaBMW]

Yeah, that's the technology in essence. The sidepods of early ground-effect F1 cars actually had airfoil cross-sections (evident if you removed the flat side panels), but after these were banned they fell back on totally flat underbodies, very low ride heights and side skirts to keep the low-pressure area trapped underneath the car.

Our cars obviously don't have sidepods that could be made into airfoils, so we're left with what we can do with the underbody and adding a front splitter and rear diffuser, in addition to whatever aero aids we could put up top (wings and the like).

My hesitation simply derives from our ignorance of the actual airflow patterns around our cars. For example, just because you cut a big hole in the front bumper doesn't necessarily mean more airflow to the radiator—it could be located in a big low-pressure area and give you no benefit at all. Same thing with extra aero—without a knowledge of how air flows around the car (i.e. wind tunnel time), it's all just groping in the dark, or trial and error (track time).

-Matt

All valid points. With the F1 cars, what would essentially happen is the low pressure area under the cars acted like suction and would literally pull the car down and give it insane amounts of grip and the like. Interestingly enough, if that ever failed or the cars caught any air, the flat underbelly would act like air foils and literally send the cars airborne.

My thing is that this technology is all good and well and it is great to know about and have. But unless you are running in the performance envelope that would make this of benefit - it just becomes aesthetics that can actually impair performance. A foil at speed can act as an aerodynamic aid. Otherwise, it can actually just act as dynamic drag on the car.

Going back to the "Wing" thing. A huge wing on your rear end does not generate enough down force at under 100 MPH to make it worth the trouble... but it sure generates additional dynamic drag as it is another piece of structure sticking out into the airflow. And you rightfully point out, we don't have specs on the airflow on these cars, though I think we should be able to find the Cd value of these cars.

Here is an interesting excerpt on Auto Aerodynamics:

Manufacturers design most cars for looks, with aerodynamics as an afterthought. As such, much can be gained by tweaking the aerodynamics of these vehicles. The unit of measurement for aerodynamics is called the "coefficient of drag" or Cd. The Cd value tells us how efficiently the vehicle slips through the wind.



Another common measurement multiplies the Cd times the total frontal area of the vehicle. This is called CdA. Lower Cd means better Mileage!

Here are things that can be done to improve your vehicle's aerodynamics:



Lower the car - Lowering the car reduces the effective frontal area, increasing efficiency. Note that this only works up to a certain point. There will be an ideal ride height for each car. According to this article (http://www.wisil.recumbents.com/wisil/demma/aero_review.htm), 2.7" ground clearance is a good minimum height to shoot for. According to Mercedes, "Lowering the ride height at speed results in a 3-percent improvement in drag."
Remove that wing - Many "sports" cars have a non-functional wing on the back. Removing it will improve the fuel economy. The exceptions are the small rear fairings that are designed to detach the airflow from a rounded trunk.
Clean up the underside of the car. - Installation of a "body pan", while a labor intensive operation, will provide a significant improvement in mileage. More.. (http://www.recumbents.com/car_aerodynamics/#Body%20pan%20notes:).
If a body pan is not practical, an air dam will redirect air that would normally pile up under the car causing drag. Not as good as a body pan, but better than nothing. Should be combined with side fairings.
Fair the wheel wells. - Yeah, this looks funny, but completely covering the rear wheel well will help improve efficiency. While the front wheel can not easily be completely faired due to clearances needed for turning, a partial fairing can be made. In addition, fairings can be added in front and behind the tires to help transition the air around these large appendages.
Clean up the front of the car. Basically the smoother the better. If the car has a large air intake under the bumper, it may not need that opening above the bumper (they are often just styling cues). An aerodynamic plastic, composite, or foam and duct tape panel can be built to cover the opening.
Remove the side view mirrors and instead use a remote camera system.
Replace large whip antennas with smaller powered antennas.
Vehicles with steep windshields can benefit from a hood fairing to help smooth the transition of air between the hood and windshield.
A small "tail cone" can be affixed the the rear bumper to help transition the air from under the car.
Side fairings can be used to clean up the lower half of the body between the tires.



Read up on F1 "Fan cars"

Huh? :dunno

[BoldUlysses]

A foil at speed can act as an aerodynamic aid. Otherwise, it can actually just act as dynamic drag on the car.

Actually, an airfoil naturally creates drag (read up on induced drag (http://en.wikipedia.org/wiki/Induced_drag)), hence the reason why you don't see any downforce-generating wings on high-speed record attempt cars (think Bonneville Salt Flats racers). So it's all a tradeoff. Is the downforce worth the extra drag?


Manufacturers design most cars for looks, with aerodynamics as an afterthought. As such, much can be gained by tweaking the aerodynamics of these vehicles. The unit of measurement for aerodynamics is called the "coefficient of drag" or Cd. The Cd value tells us how efficiently the vehicle slips through the wind.



Another common measurement multiplies the Cd times the total frontal area of the vehicle. This is called CdA. Lower Cd means better Mileage!

Here are things that can be done to improve your vehicle's aerodynamics:



Lower the car - Lowering the car reduces the effective frontal area, increasing efficiency. Note that this only works up to a certain point. There will be an ideal ride height for each car. According to this article (http://www.wisil.recumbents.com/wisil/demma/aero_review.htm), 2.7" ground clearance is a good minimum height to shoot for. According to Mercedes, "Lowering the ride height at speed results in a 3-percent improvement in drag."
Remove that wing - Many "sports" cars have a non-functional wing on the back. Removing it will improve the fuel economy. The exceptions are the small rear fairings that are designed to detach the airflow from a rounded trunk.
Clean up the underside of the car. - Installation of a "body pan", while a labor intensive operation, will provide a significant improvement in mileage. More.. (http://www.recumbents.com/car_aerodynamics/#Body%20pan%20notes:).
If a body pan is not practical, an air dam will redirect air that would normally pile up under the car causing drag. Not as good as a body pan, but better than nothing. Should be combined with side fairings.
Fair the wheel wells. - Yeah, this looks funny, but completely covering the rear wheel well will help improve efficiency. While the front wheel can not easily be completely faired due to clearances needed for turning, a partial fairing can be made. In addition, fairings can be added in front and behind the tires to help transition the air around these large appendages.
Clean up the front of the car. Basically the smoother the better. If the car has a large air intake under the bumper, it may not need that opening above the bumper (they are often just styling cues). An aerodynamic plastic, composite, or foam and duct tape panel can be built to cover the opening.
Remove the side view mirrors and instead use a remote camera system.
Replace large whip antennas with smaller powered antennas.
Vehicles with steep windshields can benefit from a hood fairing to help smooth the transition of air between the hood and windshield.
A small "tail cone" can be affixed the the rear bumper to help transition the air from under the car.
Side fairings can be used to clean up the lower half of the body between the tires.


Interesting list. I agree with all the suggestions except possibly fairing the rear wheels without some kind of scoop or NACA intake to direct air to the rear brakes.

F1 fan car (http://en.wikipedia.org/wiki/Brabham_BT46#Brabham_BT46B_.E2.80.93_the_.22Fan_ca r.22) (Chaparral (http://en.wikipedia.org/wiki/Chaparral_2J#2J) did it first).

-Matt

[Binjammin]

Huh? :dunno

http://************/25dqnba

The fan cars were claimed that if you could build a tunnel like a corkscrew, so you could drive on the ceiling, that they would generate enough downforce to hold you there.

[AquilaBMW]

Actually, an airfoil naturally creates drag (read up on induced drag (http://en.wikipedia.org/wiki/Induced_drag)), hence the reason why you don't see any downforce-generating wings on high-speed record attempt cars (think Bonneville Salt Flats racers). So it's all a tradeoff. Is the downforce worth the extra drag?

Interesting list. I agree with all the suggestions except possibly fairing the rear wheels without some kind of scoop or NACA intake to direct air to the rear brakes.

F1 fan car (http://en.wikipedia.org/wiki/Brabham_BT46#Brabham_BT46B_.E2.80.93_the_.22Fan_ca r.22) (Chaparral (http://en.wikipedia.org/wiki/Chaparral_2J#2J) did it first).

-Matt

All very interesting stuff. Yep... know about induced drag, and all that fancy Bernoulli's principle mumbo jumbo... LOL! :D


http://************/25dqnba

The fan cars were claimed that if you could build a tunnel like a corkscrew, so you could drive on the ceiling, that they would generate enough downforce to hold you there.

Thanks... and sorry Binj. I misunderstood you. Thought you meant "Fans" as in spectators, etc. :rolleyes My bad.

Interesting thought there of the cars being able to drive on the ceiling. It would tremendous aerodynamic force to keep it up there, you would need to be able to generate enough down force to keep the car and all it's weight up there. You would also have to contend with gravity won't you?

[Binjammin]

Interesting thought there of the cars being able to drive on the ceiling. It would tremendous aerodynamic force to keep it up there, you would need to be able to generate enough down force to keep the car and all it's weight up there. You would also have to contend with gravity won't you?

Well that's sort of the point. These cars weighed what, 1500lbs or whatever, and were generating more than that in aerodynamic force, coupled with the fans sucking them to the ground.

[AquilaBMW]

Well that's sort of the point. These cars weighed what, 1500lbs or whatever, and were generating more than that in aerodynamic force, coupled with the fans sucking them to the ground.

Hmmm..... here is a wild experiment idea. If you could find a wind tunnel with a fan that could generate enough force or wind velocity to simulate the car traveling at speed, you could actually have the car "static" and turn it over when the wind speed is achieved and see if it sticks... :D

[BoldUlysses]

Hmmm..... here is a wild experiment idea. If you could find a wind tunnel with a fan that could generate enough force or wind velocity to simulate the car traveling at speed, you could actually have the car "static" and turn it over when the wind speed is achieved and see if it sticks... :D

...or weigh the car, put load sensors in the floor of a wind tunnel and see if the car creates more downforce than it weighs.

Wouldn't look as cool, though.

-Matt

[samteezy]

Hmmm..... here is a wild experiment idea. If you could find a wind tunnel with a fan that could generate enough force or wind velocity to simulate the car traveling at speed, you could actually have the car "static" and turn it over when the wind speed is achieved and see if it sticks... :D

Not with the fan cars, at least - you'd have to have the car actually running at that speed, as the fan is mechanically driven, for the obscene amount of down(up?)force needed. So the car would have to be on a dyno, or at least running in neutral

(Assuming I'm understanding this correctly)

[AquilaBMW]

...or weigh the car, put load sensors in the floor of a wind tunnel and see if the car creates more downforce than it weighs.

Wouldn't look as cool, though.

-Matt

Exactamundo!

[moroza]

Aero bits for downforce? Yeah, probably useless for 99.5% of us, 98% of the time, and proper development would require windtunnel time and preferably someone who knows what they're doing; we don't want to be building CLK GTR's, after all. But plates under the trans and rear subframe (the least smooth areas under the car) would likely reduce the drag without sacrificing downforce (I really doubt these parts are creating downforce). This kind of tradeoff is pretty much an uncompromising improvement - more speed, economy, same handling, less wind noise. There's negligibly more weight and a bit more complexity, but no moving parts and it's not a mission-critical component anyway.

[attack eagle]

current F1 cars could drive on the ceiling at 60 mph. :) underbody aero is NOT part of the past.

[SlickE34]

You started a thread about what to do with sheet metal and creative ideas. That's a CNC plasma cutting table, for cutting parts out of sheet metal. It's only relevant if you take into account that it has everything to do with what you're talking about.

If I had access to a sheet metal shop? The hell with my cars, I'd make quick money building hvac and restaurant equipment. Until you have an english wheel or some other way of making compound curves, your sheet metal brake is only going to make sharp angles, like you said: good for boxes. Not something that's completely cheap from china all over ebay or anything.

Think bigger than cars, you'll make more money.


Our shop is most a full Mechanical Heating & Air conditioning/Sheet metal works. I am a Project Manager, I work in the Office, Just now putting 2 and 2 together LOL.

Making something for my car would be a after work kinda thing.

[Redfive]

Jon - Put me down for one of your underbody trays. I've been wanting to build one for years and if I'm doing the One Lap next year, every little bit of handling helps. A rear diffuser too if you can. Combine that with the huge front splitter, big rear wing, and dive planes, I'll give those big tires and stiff suspension a real workout.

The whole idea is that you're creating an upside down wing. You want the air to rush under the car faster than it rushes over it to create a low pressure zone and that pulls the car to the ground. (instead of what happens on a plane)
Most supercars have flat bottoms. That's why most of them lost the big wings after the mid 90s (Enzo, Murcielago, McLaren F1, etc) Makes a huge difference in handling at all speeds. Kris is right, on track cars it shaves seconds off laps better than more power.

Fan cars didn't use a flat bottom, but rather a flexible skirt that went around the entire perimeter of the chassis. Allowed for incredible cornering gs at all speeds, unlike wings which only work at high speeds. They were banned because if that skirt was compromised, the seal was broken and the cars would literally fly off the track.

[AquilaBMW]

Not with the fan cars, at least - you'd have to have the car actually running at that speed, as the fan is mechanically driven, for the obscene amount of down(up?)force needed. So the car would have to be on a dyno, or at least running in neutral

(Assuming I'm understanding this correctly)

Good point sir!


Aero bits for downforce? Yeah, probably useless for 99.5% of us, 98% of the time, and proper development would require windtunnel time and preferably someone who knows what they're doing; we don't want to be building CLK GTR's, after all. But plates under the trans and rear subframe (the least smooth areas under the car) would likely reduce the drag without sacrificing downforce (I really doubt these parts are creating downforce). This kind of tradeoff is pretty much an uncompromising improvement - more speed, economy, same handling, less wind noise. There's negligibly more weight and a bit more complexity, but no moving parts and it's not a mission-critical component anyway.

Very well put. I did read up again on the undertray thing, and this could actually be a rather cost effective upgrade for cars. It would improve airflow under the car - improving things like gas mileage... not matter how marginal it might be. Also, it is a form of protection for the under bits of the car. I would even suggest a rear undertray that ran from about the axles to a smidgen before the rear bumper cover there by covering the area under the rear mufflers, etc. It will clean up the air flow there.


current F1 cars could drive on the ceiling at 60 mph. :) underbody aero is NOT part of the past.

I am nominating you as the test driver :)


Jon - Put me down for one of your underbody trays. I've been wanting to build one for years and if I'm doing the One Lap next year, every little bit of handling helps. A rear diffuser too if you can. Combine that with the huge front splitter, big rear wing, and dive planes, I'll give those big tires and stiff suspension a real workout.

The whole idea is that you're creating an upside down wing. You want the air to rush under the car faster than it rushes over it to create a low pressure zone and that pulls the car to the ground. (instead of what happens on a plane)
Most supercars have flat bottoms. That's why most of them lost the big wings after the mid 90s (Enzo, Murcielago, McLaren F1, etc) Makes a huge difference in handling at all speeds. Kris is right, on track cars it shaves seconds off laps better than more power.

Fan cars didn't use a flat bottom, but rather a flexible skirt that went around the entire perimeter of the chassis. Allowed for incredible cornering gs at all speeds, unlike wings which only work at high speeds. They were banned because if that skirt was compromised, the seal was broken and the cars would literally fly off the track.

You speak like a pilot there sir... :) In actuality, you are still flying... just in a negative G environment. A plane can achieve the same thing by going inverted. Most day to day planes cannot do this though due to gravity feed fuel pumps.


To the OP and Jon, I am all for it if you guys can come up with under belly pans for the cars. I would also be curious about aerodynamic side skirts that helped feed air to the rear brakes / under belly area and inducted air from the front. I have often thought about a slight flare to the front of a side skirt - right behind the front wheel which would imitate the air intake of say an F-4 Phanthom. It would induct air by sheer slipstream and this can be chanelled under the car to feed anywhere you choose.

[BoldUlysses]

I would also be curious about aerodynamic side skirts that helped feed air to the rear brakes / under belly area and inducted air from the front.

The whole point of low ride height and side skirts is to keep air out from under the car, and to control what air is there inevitably. Much better to just "seal off" the sides and deal with what comes under the car from the front.

As far as rear brake cooling, BMW's got you covered: M-system I wheel covers! :thumbup: :D


I have often thought about a slight flare to the front of a side skirt - right behind the front wheel which would imitate the air intake of say an F-4 Phanthom. It would induct air by sheer slipstream and this can be chanelled under the car to feed anywhere you choose.

Wouldn't the airflow in that location change depending on the front wheel angle, though?

Ah, armchair engineering... :D

-Matt

[AquilaBMW]

The whole point of low ride height and side skirts is to keep air out from under the car, and to control what air is there inevitably. Much better to just "seal off" the sides and deal with what comes under the car from the front.

As far as rear brake cooling, BMW's got you covered: M-system I wheel covers! :thumbup: :D



We'll I don't gat me no M-System wheels... :(. True point about the skirts and ride height and all that. However, if you could "control" the air that went under the car - actually direct, I think it could be interesting. So... imagine this (In my best Jeremy Clarkson voice), you have a side skirt with an air duct opening that channels air into an underbelly of the car. You then have a rear diffuser at the end of that under tray that acts like an inverted wing. Down force achieved! Rear spoiler eliminated! Also... with air flow cleaned up "around" the car, it might create less turbulence at the back of the car... (this one is up for major debate... :D)



Wouldn't the airflow in that location change depending on the front wheel angle, though?

Ah, armchair engineering... :D

-Matt

Yep... of course it would. However, you plan for the configuration the car will be in most of the time and that is with wheels pointing forward.

Gotta love us armchair engineers... :D

[BoldUlysses]

So... imagine this (In my best James May voice)...

Fixed. Monsieur Clarkson would become nauseated by such tech-speak. POWER!!!

:D

-Matt

[AquilaBMW]

The whole point of low ride height and side skirts is to keep air out from under the car, and to control what air is there inevitably. Much better to just "seal off" the sides and deal with what comes under the car from the front.

As far as rear brake cooling, BMW's got you covered: M-system I wheel covers! :thumbup: :D



Wouldn't the airflow in that location change depending on the front wheel angle, though?

Ah, armchair engineering... :D

-Matt


Fixed. Monsieur Clarkson would become nauseated by such tech-speak. POWER!!!

:D

-Matt

HE HE HE.... You do make a very valid point there. :D