Carbon rear diffuser
 

Hi. Does anyone have any links to places that sell the carbon fibre rear diffuser kits for the rx8.
Thanks

Nope. Custom is the only option. Well for a real functioning diffuser anyway.

Agreed on what/how much performance you want out of this diffuser.

@9k, there are some Japanese products that are carbon fiber rear diffusers.

Only by name, none of them are actually functional.

The only one that has been proven to be effective is the Mazdaspeed version

Well he never asked for functional improvements of any sort, just if there were any CF diffusers out there.

Well if it does not diffuse then it technically not a diffuser.

In that case it's just a reverse rice bowl.
No diffuser will do much unless you cut the rear bumper, seal the whole rear etc.

here you go.

i made brackets to fit one like this to fit nukes car.. fit was good on that one..

link

beers :beer:

I have one like that...a MS rear that was custom carbon covered....sitting in my attic

Suppose I should sell it..or put it on the car ;)

yep,

or take the carbon off and sell it as a real MS part. seems that is where the money is now.. :)

beer :beer:

Nice piece too bad its expensive for a replica part that probably dosent fit

Leg Sports makes one too. As to whether or not it is functional- doubt it. I'm personally going with an RE Amemiya FD diffuser for mine, but that's going to require some creativity lol.

@rods that thing is nice as helll lol

Pretty much for anything that just tacks onto the OE bodywork, so just cut the rear bumper out as below and then custom CF an enclosure ...


https://cimg9.ibsrv.net/gimg/www.rx8...4d23ef5688.jpg


JIC RX8

Re-amemiya diffuser; If diffuser are not functional, why do companies make them? All aero kits from reputable rotary shop make their kits for circuit use, battling down-force at speeds excessive of 200km/hr. Selling parts is secondary to their business.

My 2 cents.


https://cimg5.ibsrv.net/gimg/www.rx8...fd2323e12c.jpg

Exactly what I plan on doing with mine. Also planning on having a friend fabricate a complete flat underbody.

Most of the crap that is made is because of the gullible people willing to buy it or they just don't understand aero any more than yourself. As long as you have an OE size muffler in that position and bring your diffuser in underneath it then it's basically BS. Even in the pic I posted that big canister us an issue even if it had a proper diffuser plate positioned up close to the bodywork.

Instead of placing your faith in F&F mindset engineering try researching and educating yourself on diffuser theory and whst it actually requires to be truly functional. I don't mean any of this as harshly as it probably comes across. Just because something is popular or common doesn't mean squat. Just like all the people on here that have a misguided fantasy that a header with long tubes on a Renesis has to be end all of power perfection.

Can you see the differences here? The low positioning, low angle, enclosure, length or projection out the back, etc. is important. In the pic you posted the open cavities ahead of and above the muffler just relegate it to an expensive air brake scoop ...


https://cimg2.ibsrv.net/gimg/www.rx8...e5f92f9cd9.jpg


https://cimg3.ibsrv.net/gimg/www.rx8...e000d4afc9.jpg



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https://cimg5.ibsrv.net/gimg/www.rx8...036e9d8068.jpg

about 9-10 degree is the maximum tilt you want from a diffuser to create any downforce, otherwise it'll just create vortex/drag which is what all our bumpers are doing. You also need a full underbody covered to actually utilize a diffuser. I bought sheets of alumalite couple years ago to make one, but it's complete PIA! You also need some roller/glass work to make it somewhat stock, not like a tacked on cardboard by a 7yo.

^^^ The smoothed chassis bit is the absolute truth. Even if you have a working diffuser, it will still catch a decent percentage of the air under the car and cause some drag, effectively neutralizing its own effectiveness.

Also for any real effectiveness, the car needs to be extremely low. I can't remember where I read it, tho I know if was written by an experienced aerodynamics tech, the best height is 1 inch from the ground and you dramatically lose effectiveness the further away you get. Hence why you see every Super GT and most time attack racers practically laying on the ground.

I am not expert, but I have done quite a bit of "read-search" about areo...
Check out this Link . Its a good read and simplistic... but may give you a clearer understanding of how much work it its to make an effective aero under belly. oh and you may want to start from beginning of Thread i linked...

https://cimg7.ibsrv.net/gimg/www.rx8...2d64bacd26.jpg