View Poll Results: Vote on what one you are seriously interested in buying:
I am interested in the radiator ducting
17
9.39%
I am interested in the underpanel/front splitter
34
18.78%
I am interested in both
130
71.82%
Voters: 181. You may not vote on this poll
interest in custom radiator ducting and undertray/front splitter combo?
#76
Eats, Sleeps, Dreams Rotary
Join Date: May 2003
Location: MIA
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Originally Posted by damian
carbon fiber = too much $$, and the taklam was very light, did you read the previous posts on the weight?
carbon fiber skins on the nomex honeycomb would not gain major weight reduction, but gain serious cost.... also the skin would be a bit stronger....but again, in my case not enough for the big price jump
if you read my first posts my goal was a light 'exotic' material...like carbon fiber, but not nessisarily carbon fiber, ...although if i had another 1000 to spend on it I would go carbon fiber cuz its cool ;-)
carbon fiber skins on the nomex honeycomb would not gain major weight reduction, but gain serious cost.... also the skin would be a bit stronger....but again, in my case not enough for the big price jump
if you read my first posts my goal was a light 'exotic' material...like carbon fiber, but not nessisarily carbon fiber, ...although if i had another 1000 to spend on it I would go carbon fiber cuz its cool ;-)
Yes yes, I read the weight difference I thought it was between the aluminum and carbon fiber. I mixed up the parts you were making.
Ok np.
#77
i dont think is causes lift, its actually still creating downforce from smoothing out the air that gets under there and really restricting how much air can go down there... what your talking about is eliminating turbulance at the edges, that would be helpful and i may add some runners, but its not high on the list as the benefit is low vs the work in labor/materials to do it.
#78
Originally Posted by GoRacer
Is it ok for it to be flat without any defuser type waves/splits? The oem version has runners/ridges or whatever they are called. Will a flat version cause lift?
The underbody scheme is as follows:
- The front needs to be completely flat, smoothing out the air coming under the car
- Loading tunnels/runners should begin before the center of gravity (which is prob somewhere around where the seats are).
- The tunnels/runners should encompass at least 25% of the length of the car, ending in a diffuser
- The ramp of the diffuser should angled at a minimum of 17 degrees and be of sufficient length to properly evacuate the rear of the car
Of course, doing the above requires completely sealing the underbody of the car (which I'm REALLY curious if Damian would go for, cuz I sure would if he offered it!) Very few cars have such a setup, such as the Ferrari F40/50, and the Chystler ME 4-12.
The other alternative is to do what you can, within reason. That becomes a very flat front undertray extending as far back as possible, and a rear diffuser of sufficient length w/ a properly angled ramp. Allow me to illustrate...
Flat front undertray
Diffuser + ramp
A closeup of the diffuser ramp...
#80
dood, i love this post!!! it sums up all im trying to do with the undertray/splitter.
...and yes, i am looking at a set of parts that seals the entire bottom. :-) that will come later...much later.
concidering the coverage i got with my design, and that it is totally flat, and that is acts as a splitter also, i think its pretty dam good :-)
...and yes, i am looking at a set of parts that seals the entire bottom. :-) that will come later...much later.
concidering the coverage i got with my design, and that it is totally flat, and that is acts as a splitter also, i think its pretty dam good :-)
Originally Posted by FDNewbie
There definitely aren't "runners" anywhere near the front of the car. That's a very bad idea aerodynamically. What you're talking about is prob. the radiator ducting...
The underbody scheme is as follows:
- The front needs to be completely flat, smoothing out the air coming under the car
- Loading tunnels/runners should begin before the center of gravity (which is prob somewhere around where the seats are).
- The tunnels/runners should encompass at least 25% of the length of the car, ending in a diffuser
- The ramp of the diffuser should angled at a minimum of 17 degrees and be of sufficient length to properly evacuate the rear of the car
Of course, doing the above requires completely sealing the underbody of the car (which I'm REALLY curious if Damian would go for, cuz I sure would if he offered it!) Very few cars have such a setup, such as the Ferrari F40/50, and the Chystler ME 4-12.
The other alternative is to do what you can, within reason. That becomes a very flat front undertray extending as far back as possible, and a rear diffuser of sufficient length w/ a properly angled ramp. Allow me to illustrate...
Flat front undertray
Diffuser + ramp
A closeup of the diffuser ramp...
The underbody scheme is as follows:
- The front needs to be completely flat, smoothing out the air coming under the car
- Loading tunnels/runners should begin before the center of gravity (which is prob somewhere around where the seats are).
- The tunnels/runners should encompass at least 25% of the length of the car, ending in a diffuser
- The ramp of the diffuser should angled at a minimum of 17 degrees and be of sufficient length to properly evacuate the rear of the car
Of course, doing the above requires completely sealing the underbody of the car (which I'm REALLY curious if Damian would go for, cuz I sure would if he offered it!) Very few cars have such a setup, such as the Ferrari F40/50, and the Chystler ME 4-12.
The other alternative is to do what you can, within reason. That becomes a very flat front undertray extending as far back as possible, and a rear diffuser of sufficient length w/ a properly angled ramp. Allow me to illustrate...
Flat front undertray
Diffuser + ramp
A closeup of the diffuser ramp...
Last edited by damian; 10-14-04 at 02:36 PM.
#81
Originally Posted by damian
dood, i love this post!!! it sums up all im trying to do with the undertray/splitter.
...and yes, i am looking at a set of parts that seals the entire bottom. :-) that will come later...much later.
concidering the coverage i got with my design, and that it is totally flat, and that is acts as a splitter also, i think its pretty dam good :-)
...and yes, i am looking at a set of parts that seals the entire bottom. :-) that will come later...much later.
concidering the coverage i got with my design, and that it is totally flat, and that is acts as a splitter also, i think its pretty dam good :-)
Oh man Damian...if you actually do get to the point where you make the entire thing...just WOW. I say patent it, and find someone (like Chuck) who can mass produce it and offer it to the public at a large scale...while you sit back enjoying a %age of the profit and some royalties haha
Last edited by FDNewbie; 10-14-04 at 04:22 PM.
#82
I am very interested in this "project" since Corksport has not come through with a Mazdaspeed front undersweep although it's been almost a year.
How will this undertray work with a 99' OEM nose?
How will this undertray work with a 99' OEM nose?
#88
Just in time to die
iTrader: (1)
I have something very similar on my GTS, and have something for my V-mount setup on my 7 mocked up as well. The problem you may run into with V-mount setups is they all angle the radiator differently. So the ducting cant really be universal but it should work as just a undertray at least, which would get them halfway there. Looks like good work so far.
#89
here is a pic of the diffuser i just installed, you can see the undertray under there too:
here is more pics of the diffuser:
https://www.rx7club.com/showthread.p...29#post3605029
here is more pics of the diffuser:
https://www.rx7club.com/showthread.p...29#post3605029
#91
Originally Posted by Zero R
I have something very similar on my GTS, and have something for my V-mount setup on my 7 mocked up as well. The problem you may run into with V-mount setups is they all angle the radiator differently. So the ducting cant really be universal but it should work as just a undertray at least, which would get them halfway there. Looks like good work so far.
I assume the good point of this is it causes less impedence for air to flow through the radiator, since it has a clear path to exit, right? So having a completely sealed undertray will create somewhat of an impedence, right? If so,
1) I think the speeds at which you're really gonna be using both the radiator and undertray, there will be more than enough force to push air through the radiator, and
2) If you're running a vented hood (that actually works lol) I'd see it solving the impedence problem, AND being more aerodynamically stable, since this air is now exiting the top of the car. And I think some vented hoods (such as the Mazdaspeed one) can actually generate downforce in such a manner (whether directly, or indirectly by reducing lift, I'm not sure). Keep in mind, air exiting via a vented hood also helps disappate heat from the engine bay, too.
3) The way Damian is designing the undertray, it extends beyond the oil pan. I'd say that would have even greater benefits, since the air that doesn't exit the engine bay through the vented hood would have to exit further back, after it passes by the oil pan, thus hopefully disappating some of the heat generated by the hot oil...
If I'm way off, plz break it down for me.
Oh and Damian, that's a old RE diffuser, rite? I bet you get some SERIOUS downforce w/ that special center channel you got there! Seriously, what are you doing w/ a U-haul hitch on your FD? That's such a no-no...esp for a track car! You use it to haul your tires/rims w/ ya to the track?
Last edited by FDNewbie; 10-15-04 at 12:14 AM.
#93
Just in time to die
iTrader: (1)
Your not way off at all, there are a couple solutions as to where you could help direct the air, the simplest would be to direct it through the front wheel area since that is a aerodynamic mess to begin with, you are really limited with what and where you can go without really tearing apart the car and reworking everything. Which I have been contemplating lately.
#94
Originally Posted by Zero R
What made you switch to this diffuser?? just curious. I have a diffuser made into the rear bumper of the GTS and run a RE carbon on the 7. The Viper is pretty much all flat bottom at this point.
if you mean why did i choose this instead of the re pro version i also have (never installed), its because this one works better with the hitch and i like the aero shape of this one better.
#95
>>Oh and Damian, that's a old RE diffuser, rite? I bet you get some SERIOUS downforce w/ that special center channel you got there! Seriously, what are you doing w/ a U-haul hitch on your FD? That's such a no-no...esp for a track car! You use it to haul your tires/rims w/ ya to the track?
just answeed this question in my diffuser thread. go read there LOL....
just answeed this question in my diffuser thread. go read there LOL....
#96
Originally Posted by SyderJL
This project is turning out great!
Question for ya: Is the underpanel angled down or up or is it level when it is installed??
Justus
Question for ya: Is the underpanel angled down or up or is it level when it is installed??
Justus
#97
FDNewbie summed it up in a previous post, with a vented hood and my radiator ducting, the air has easy flow out of the hood to the top side of the car (thats what you want) and the undertray limits and smooths the air that gets under (more of what you want).
the biggest thing about this undertray/diffuser stuff is that you are increasing downforce without increasing drag.... vs a wing that creates downforce but also drag.
the biggest thing about this undertray/diffuser stuff is that you are increasing downforce without increasing drag.... vs a wing that creates downforce but also drag.
#98
Originally Posted by Zero R
Your not way off at all, there are a couple solutions as to where you could help direct the air, the simplest would be to direct it through the front wheel area since that is a aerodynamic mess to begin with, you are really limited with what and where you can go without really tearing apart the car and reworking everything. Which I have been contemplating lately.
"At rest, its lines are unmistakably those of a Porsche. The silhouette undoubtedly that of a 911. Once in motion, you will notice something different: a sports car whose unabashed charisma is elevated by an extra-ordinary sense of control.
How can so much power be choreographed with such precision on the open road? The answer is in the air. Rather than settling on a "hydroplane" approach that merely deflects air around the car, our engineers have spent endless hours in the wind tunnels at Weissach devising aerodynamically efficient features that actively enlist the air as an ally in reducing lift and drag while simultaneously cooling vital engine, transmission and brake components.
The leading-edge design of the 911 Turbo and 911 Turbo S begins at the front bumper, where a discreet spoiler lip reduces front-axle lift by diminishing the amount of air passing beneath the car.
Instead, the wind is swallowed by black-lined ducts feeding three radiators that boast 50 percent more surface space and a 10 percent increase in cooling capacity over the previous 911 Turbo generation. Internal spoilers are also used to enhance brake cooling before venting the air through slits that act as invisible spoilers to lower drag at the front tires.
Aerodynamic synergies continue in back, where a rear wing spoiler lessens lift and drag as it channels cool air into the engine compartment. Crescent-shaped intakes corral the wind along the sides of the car to satisfy the twin turbo-chargers' thirst, while meticulously sculpted panels work down below to keep air gliding beneath both Turbo models, creating a 'ground-effects' stream that simultaneously optimizes ventilation of the front differential and gearbox. The smooth underbody prevents lift forces from gaining a grip and helps drive the coefficient of drag value down to a low 0.31 -- while maintaining a thrill factor that races off the charts."
And from a diff site (this one has some solid #s, as to show you it would def. be worthwhile, Zero, if you're gonna see some serious speeds in the FD!):
"Porsche takes aerodynamics seriously, and when you design your cars to be stable at 180 mph or beyond, you probably have to. New front air intakes increased airflow to the radiators by 15 percent. Reshaping the front wheel arches and adding small flexible spoilers ahead of the front wheels reduced aerodynamic lift by 25 percent at the front and 40 percent at the rear. New air intake ducts enhanced front brake cooling, while a new under-floor duct enhanced transmission cooling by 20 percent. The rear spoiler deploys automatically at higher speeds, when more downforce is advised.
The 911 Turbo is distinguished from the Carrera models by three large intakes that dominate the lower front fascia and provide cooling air to the car's three radiators. The Turbo also has a wider stance, particularly at the rear, where its fenders spread 2.6 inches wider to accommodate even larger rear wheels and tires (295/30ZR18s on 18x11-inch rims). Air scoops integrated into the leading edges of the rear fenders channel cool air to the turbo intercoolers, while louvers in the sides of the rear cover let the hot air out. The engine compartment lid carries a two-piece rear wing, the upper part of which automatically rises at speeds above 75 mph and lowers at 50 mph."
I couldn't find closeup pics of this...but I remember one of the Best Motoring videos (I think) did an in-depth study of the new 911 Turbo, and went through all of this, including showing close-ups of the vents, the internal spoilers, and discussing the aerodynamics involved. Simply amazing...
Last edited by FDNewbie; 10-15-04 at 12:59 AM.