F1 BT45 B Fan Car to Pro-Touring adaptation...Lol?

[Chadman27]

Ok, so entertain this idea for a sec...

I was going through some Youtube videos of F1 advancements throughout the decades and I learned about the BT45 B Fan Car that was quickly banned by the FIA after one race. See videos here:

https://www.youtube.com/watch?v=ScBCoOv50dA

https://www.youtube.com/watch?v=acq8BvIhUTg

So... could this novelty be adapted to a dedicated autocross or 1Lap car? Now before you shoot this down totally, I think there are some physics obviously at play which would make this NOT work for "our" application, but I digress...

(a) Would an "Old School" muscle car even be low enough for any sort of vacuum to be effectively generated...

(b) This would instantly "ban" you from any regulated class in SCCA, NASA, etc, etc... but... for bragging rights of an FTD... could be plausible? Would Optima Ultimate Street Car rules allow this (who is gonna slam a car and suck it to the ground?!?! :rotfl:)

(c) The only logical position for a fan in a factory passenger car would be the trunk and ducted to the rear passenger seats (deleted obviously), so I am guessing it would be near impossible to mechanically be driven off a crank pulley, and would require an electric fan. Could sufficient power and fan RPM be generated off an electric source (car battery... something else?) to even get you this power demand? Even if the fan power draw demand could be met, how long would it last... enough for a 1 lap or autocross run?... maybe.

Anyways, I just thought it was very entertaining seeing this, and it sparked my mind of the possibilities. Any effectively adapted system is way beyond my patience and budget, but I figured you guys are the best on the web so punch holes in this idea and or construct some plausible solution. I will never be able to do it... but, if anything else lets have some fun and have some discussion, so please go!

[Chadman27]

Incorrect title, make that BT46 B, not 45.

[Chadman27]

BTW, I hear Dyson and Oreck makes some pretty good vacuums... I wonder if my mom would mind riding trunk, I mean it would be just like the living room carpet right?:pat:

[TheJDMan]

It would be an interesting design excersize.

[vette427-sbc]

Ok, so entertain this idea for a sec...

I was going through some Youtube videos of F1 advancements throughout the decades and I learned about the BT45 B Fan Car that was quickly banned by the FIA after one race. See videos here:

https://www.youtube.com/watch?v=ScBCoOv50dA

https://www.youtube.com/watch?v=acq8BvIhUTg

So... could this novelty be adapted to a dedicated autocross or 1Lap car? Now before you shoot this down totally, I think there are some physics obviously at play which would make this NOT work for "our" application, but I digress...

(a) Would an "Old School" muscle car even be low enough for any sort of vacuum to be effectively generated...

(b) This would instantly "ban" you from any regulated class in SCCA, NASA, etc, etc... but... for bragging rights of an FTD... could be plausible? Would Optima Ultimate Street Car rules allow this (who is gonna slam a car and suck it to the ground?!?! :rotfl:)

(c) The only logical position for a fan in a factory passenger car would be the trunk and ducted to the rear passenger seats (deleted obviously), so I am guessing it would be near impossible to mechanically be driven off a crank pulley, and would require an electric fan. Could sufficient power and fan RPM be generated off an electric source (car battery... something else?) to even get you this power demand? Even if the fan power draw demand could be met, how long would it last... enough for a 1 lap or autocross run?... maybe.

Anyways, I just thought it was very entertaining seeing this, and it sparked my mind of the possibilities. Any effectively adapted system is way beyond my patience and budget, but I figured you guys are the best on the web so punch holes in this idea and or construct some plausible solution. I will never be able to do it... but, if anything else lets have some fun and have some discussion, so please go!


Dont forget about the Chaparral 2J!

and to answer some of your questions:
A) Sure you can lower a car as much as you want. Getting ground effects that seal it off may be difficult if you still need it to look good (although, function is form, right?)

B) read about how the BT46 B got away with using the fan in accordance to the rules... Im going to assume movable aero is not legal for most classes

C) It could be run off of the driveshaft, or like the chaparral with a separate engine (or two!)

Im a huge fan of the "out of the box" race car designs from past race cars... especially the CAN-AM series stuff

[Cobra 498]

A friend and I started developing a system using two high efficiency fans directly driven by two vertical shaft rotary mower engines. The plan was to mount them in side pods just big enough to
clear the blade arc and seal the whole periphery of the car with conveyer belt cut to the correct length to seal to the road but maintain a seal as the car moved through suspension travel.
The fans we used were based on a truck design and were 5 bladed and moved lots of air. The total area under the car is quite large so that if you can pull only a small amount of vacuum you get lots of down force with no wing drag. We built a test rig using plywood which collapsed the first time it was tried from the vacuum it created, it would also pick up trash, rocks ETC and throw them up in the air making it a safety hazard. The other problem that we thought about was if there was a blade failure bystanders or the driver could conceivably be injured or killed. We gave up at that point but it certainly is feasible. I think some guys tried it with a formula SAE car or something like that in autox and SCCA immediately banned the use of sucker fans. Jim Hall used a snowmobile engine on the Chaparral. The good thing is that you have down force even at very low speeds as opposed to wings. I may be remembering this wrong but I think Hall was the first guy under a minute with that car on the old Laguna Seca race course.

[Tom Welch]

I think it would be an excellent development exercise, just as the use of a gyroscope to keep a car level through hard corners would be.

[HellPhish89]

I think it would be an excellent development exercise, just as the use of a gyroscope to keep a car level through hard corners would be.

would be simpler to adapt a self leveling suspension system to do that ;)


in any case.. there are a few ways to do it but remember that the Chaparral was the first. the f1 version was short lived because it was a rotary blade on the back of the car connected directly to the drivetrain.

the hardest part is figuring out your airflow requirements. i personally think you could adapt the compressible mass flow equation to do it in conjunction with your standard downforce calculations.

otherwise.. its just engineering.. figure out the simplest and most robust way to get air out from under the car. find some high flow fans that can be run off 12v and go from there.

[Cobra 498]

would be simpler to adapt a self leveling suspension system to do that ;)


in any case.. there are a few ways to do it but remember that the Chaparral was the first. the f1 version was short lived because it was a rotary blade on the back of the car connected directly to the drivetrain.

the hardest part is figuring out your airflow requirements. i personally think you could adapt the compressible mass flow equation to do it in conjunction with your standard downforce calculations.

otherwise.. its just engineering.. figure out the simplest and most robust way to get air out from under the car. find some high flow fans that can be run off 12v and go from there.

You would need on the order of 625 amps @ 12volts to move a significant amount of air from under the car, you could always put a Honda generator in the back seat :)

[Chadman27]

Sounds pretty cool!

Maybe if there is enough interest we can get an aftermarket company like DSE or Ridetech to develop a "bolt on" kit :hammer:

[j-c-c]

See pic #51, although its almost tongue and cheek, it can't hurt to lower under chassis aero under almost any circumstance.
http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=7972701&page=0&fpart=1&vc=1

[snopro]

Im actually putting the rad in the back of my truck and going to duct the air from underneath and hope the fans pull enough to cool it and maybe help with downforce even a little? but this is getting two birds stoned at once by moving more weight to the rear. its worth a shot I guess lol

[HellPhish89]

Im actually putting the rad in the back of my truck and going to duct the air from underneath and hope the fans pull enough to cool it and maybe help with downforce even a little? but this is getting two birds stoned at once by moving more weight to the rear. its worth a shot I guess lol

you would get more doing something more liike this:
http://www.speedhunters.com/2012/06/for-my-ally-is-the-force/

[Buryingthesun]

you would get more doing something more liike this:
http://www.speedhunters.com/2012/06/for-my-ally-is-the-force/

Cool car idea. . . Guys a ***** for having s-bends in his down tubes and then bolting the cage together on a car with so much engineering