RotorMotor

iTrader: (5)

well, rear downforce is easy... just buy a big *** ricer wing and you can have all the downforce you want in the back. add to that a diffuser under the gastank (some say its worth it some say not) to smooth out flow under the rear of the car and thats about all you can do... short of engineering some sort of venturie tunnels to SUCK the car down.

anyway, downforce in the back is easier to obtain... but the problem is when you add a huge stupid ricer wing to the back, you make the front end lighter, making the situation up front even worse than with no spoiler at all. so considering we can easily add basically however much D.F. to the rear.... how can we plant the front better at high speeds?

ill throw out 2 things to start:
1) smoothing out flow under the front of the car (which damian has been exploring recently with some coustom underbody pannels)
2) the addition of the '99 front lip (or equivalant sort of splitter)... it does have a good pitch to it, but im not sure how much downforce it actually generates... i believe the main benefit of the lip is to evacuate some air to the sides of the car where the little "side flares" are.

basically the purpose of this thread is to talk about and explore new/old methods for generating downforce in the front of the car(with an emphasis on minimized additional resistance, although that IS one of the big tradeoffs to downforce).... so... lets talk. -heath

akiratdk

Lowering the car will help from negative pressure building up under the car.... we can imagine the car being like an airplane wing... Downforce for the front end... I guess building a wider body will help dramatically.... more surface area...more pressure builds on top of the car. my 2 cents.

KaiFD3S

iTrader: (37)

That's why they make those front diffusers, the one's that attach to the sides of the front bumper, I'm not sure what they are called but you see them a lot on cars with body kits

jimlab

One word: cannards.

spekdah

go to an F1 tech site ( should be sumthing) you may as well learn and understand from the best, maybe after that you can apply it to FD's

KaiFD3S

iTrader: (37)

Thank you Jim, I knew I could count on you....

RotorMotor

iTrader: (5)

unfortunatly i believe no company produces cannards for the FD....

KaiFD3S

iTrader: (37)

there's a lot of universal one's that will fit....

RX7Wishing

^ yup

RotorMotor

iTrader: (5)

i know... but its kind of a shot in the dark without propper testing. im not opposed, BUT (especially when it comes to stability at insanely high speeds) im a bit worried to add un-tested stuff that could upset the front and possibly lead to a high speed disaster. not saying that i wouldnt try out things, just that id like a way to measure WHAT effect its having on the car before i take it even faster. i have an old beat up bumper assembaly that i wouldnt mind swapping onto my running FD if i could have a way to measure effects of different alterations to it... well i guess there is always seat of the pants measuring as well.

another question: as far as air vents such as on the elise, gt-40, and various other cars... are they just used for cooling, or does the internal angle of the outlet add any downforce??

RotorMotor

iTrader: (5)

know any links? know anyone that has used these before on an FD?

Mahjik

iTrader: (1)

I was waiting for "V8".

jsplit

Just search google and you'll find some universal ones.

( http://shop.store.yahoo.com/sgpracin.../caficaun.html )

I might just be tempted to try and fab some on my own, I need a new project anyway.

lopedl

iTrader: (1)

I would think ducted hoods (like the scoot hood) and also, channeled mirrors like ones on re-amemiya vehicles would also contribute to downforce. Since the air that flows through the ducts would help stabalize the vehicle.

USCmatt

http://rxecret7.com/cwesbumcar.html
http://rxecret7.com/frbuca1.html
http://rxecret7.com/panspgt20frb.html
http://www.jt-imports.com/FEED_FD_Parts_List.htm

DamonB

The closet aerodynamicists around here should stay in the closet.

ROTORhead93

I saw this on JT imports.

FEED Original bumper fin set



so for those of you with the 99 spec front end, you can get cannards to aid in front end downforce.

Now if only someone fabricated some for the 93-95 front end. Any takers? Damian?

DamonB

Yes to both. The air that enters the inlet is ducted through the cooler(s) and when sent down a properly designed exit duct can be used to generate downforce on the front as well. This is at the expense of sending heated air over the car which tends to effect things in the rear. This is why nearly every clean sheet of paper racecar uses hip radiators and carefully controls where the warmed air is routed.

Ride height in and of itself doesn't contribute downforce. Rake contributes downforce.

mad_7tist

but nothing beats some high speed dynamic testing. remember the benz race cars flying off the track? you would think those guys would have a handle on things but **** happens

R. Gambino

Take a look at the Nov. issue of Racecar Engineering (it's a Brittish mag.). There is an article on just this subject (front end downforce). Oct issue delt with air dams, this one is on splitters.

Falcoms

That is by far one of the best magazines I have ever read. Problem is, price reflects this fact IMO.

Why not go world of outlaw's style and put one of those tuner wings in the front of the car to?

teamstealth

What about the ducts on the front of the Porsche GT2 bumper? Those would be pretty easy to replicate with a duct coming off the back of a FMIC/SMIC and just pull the duct upwards. Might have to duct it into a vented hood like the KS or MazdaSpeed....just a thought

http://hk.geocities.com/forte_lsm/im...orsche/GT2.jpg

3PointApex

How does the Mazdaspeed GT-C front bumper measure up for downforce? I know it's good for increased airflow into the engine bay, but is the (rather aggressive) lip on the bottom effective?

RotorMotor

iTrader: (5)

can you explain a bit about the effects of the heated air over the top of the car? basically there are a few things preventing this sort of design on the FD... (well first off there are not enough owners to make this practical)... but besides that you would have to move the radiator and the intercooler to make room for that type of air channel in the front. a radiator could sit at the top of the channel, however that may impede some airflow and reduce downforce (but it seems you would get WAY more than currently exists).... second would be to deal with the placement of the intercooler. it would be very interesting to relocate the intercooler UNDER the car (with a scoop on the botton of the car to pick up cool air and direct it towards a coustom intercooler.... a brick type (deep, and wide... but not tall) would work well under the car.... the scoop which could extend slightly below the underbelly cover would also create downforce which would be a plus. add to that a very simple flow path from the turbos (under the car, right bend to IC, and back to the top on the drivers side to the throttle body) ... would also increase turbo efficiancy. so added benifits of said modifications (if it could be pulled off) would be -> downforce generated from sealed outlet channels from bumper through hood, better cooling for radiatior (not impeded by IC, and not blowing hot air back into engine compartment), downforce generated from air scoop under car to feed couston intercooler setup, colder intercooler via dedicated IC scoop, simplified turbo piping w/ less bends and less length = more efficiant turbos and better turbo response. soooo... combine all that with a nice smooth under belly pannel like damon's, add a splitter, and some cannards on the sides.... and you will have a really great track/street car which will STICK to the road the faster you go. then balance that with a RICER wing on the back (but hopefully something more tasteful), cause you will actually need it to counter the extra downforce in the front. it would be fun.... someone get to work

teamstealth

^ a little less complicated version of that idea

What about the people that have a V mount setup....They could take damian's new underbelly tray, cut a duct in on the bottom with a very small lip to catch air from underneath the car, and force it upwards through the radiator. Then build a short splitter from the bumper inlet to seal off the top of the radiator and the bottom of the IC, then build a duct from the top of the IC up through the vented hood. That way you'll have two sealed, ducted inlets (bottom of car through the rad/ic, and one from the front going over the face of the rad and up through the ic)