I found this from an old thread about this Soarer in Japan:



Thread itself:

https://www.clublexus.com/forums/sc-...en-before.html

I don't like much on that car but that rear diffuser is excellent, and apparently NOT a photoshop. Does anyone know what that rear diffuser is from? I'm sure there are other cars with a similar curve and the same distance between exhaust holes- it would be great to install one on our cars.

 

Welp, answered my own question. It's the diffuser from the IS-F. *duh*

The 2nd-gen IS bumpers are actually of very similar dimensions to our cars, so this should work (photos are to scale at a width of 70.9" on the IS and 70.5" on the SC)



Diffusers are available for less than $100 in fact
http://www.ebay.com/itm/Fit-06-07-08-09-11-12-13-Lexus-IS250-IS350-4Dr-Mr-Style-Rear-Diffuser-Bumper-Lip-/131275982868?hash=item1e90a88814&vxp=mtr
The main challenge would be making it fit the curve of the SC. Some sort of filler material is likely necessary, and based on the curves, they would sit on the 97+ bumper much more naturally than the older one.

 

instead of filling it I would just trace it out on the car and trim the bumper to fit the diffuser. then the lines would match correctly with no filler. it actually looks like that is what they did notice a good part of the stock bumper is missing. Bring your car over I got 30 minutes and a Dremel =)
you are right it looks like you need the 97+ side rear bumper sides though to make it flow together.

 

Too bad that diffuser doesn't work.

Diffusers on production vehicles (with the exception of exotics, like Ferrari) are fake; they're aesthetic only.
For a diffuser to work, there needs to be an open space where the fences (fins) are located. This opening out the back, serves as an exhaust port for the air thats flowing beneath the vehicle; ultimately producing what's called the "Venturi Effect" ... It's a suction, increasing the flow of incoming air from the front. Therefore you can't have an OEM bumper shape; it won't work. That's really all they do these days however, is put fins on an OEM bumper, and then call it a "Diffuser". It's not a diffuser; it's an imitation only, that does absolutely nothing besides "look cool". The angle also needs to be different than what you see here; research shows that diffusers work best at 8° of angle.

Furthermore, and this isn't to burst your bubble or anything, it's just the truth ... For a diffuser to really work effectively, you need an underbody-tray, so that the airflow has a straight path beneath the vehicle.

When you increase flow in an area, you then reduce pressure in that same area; therefore the surrounding atmospheric pressure imposes upon that area, producing a suction known as: "Bernoulli's Principle". So basically an underbody-tray, along with a diffuser, works like a rear-wing (or an inverted-airfoil). It literally sucks the car downward, glueing it tighter to the ground.

These bumpers do nothing.

 

Haha i'm well aware. They just look modern, and cool.

 

They do look cool, but sc would look even better if it's done right. To be honest it the spare tire well wasn't there, it would be easier to make a great race looking cf diffuser that looks great and functions on the highway and the track.

I always thought scs look great without the rear bumper raw and secy😎

 

the RX7 FD Amemiya diffuser, which is functional, fits on the SC as well, a member has done it here
http://www.ebay.com/itm/261976771026?_trksid=p2060353.m1438.l2648&ssPageName=STRK%3AMEBIDX%3AIT

 

lol i agree, MOAR COOL PLZ!

jokes aside, this is a great idea.

ive been looking for a cool diffuser but it seems no one sells a "kit" like product for our car.

other's attempts have been A for effort/creativity but not very tasteful.
(just because its possible doesn't always mean you should do it)

 

May be something in the line of this one

 

THAT'S SICK!

$205 Shipped???

I might get this in the near future.
I've been thinking of using sheet-metal to make an under-tray.

 

i dont know if you know this but...i hope your not confused. that part is only for the little carbon fiber side pieces only for 205 shipped LOL so expensive for little pieces
(if it was the whole thing then yes this would be much deal haha)

 

oh yea i didn't realize, here's the whole thing, wrong link
http://www.ebay.com/itm/Mazda-RX7-FD3S-JDM-RE-Amemiya-Style-FRP-Rear-Diffuser-Kit-USA-CANADA-Undertray-/131501244916?hash=item1e9e15c1f4&vxp=mtr

 

found this "rear lip/diffuser" as the site states lol

http://www.jmautosports.com/duraflex...p/g-76478.aspx

this is a Rear bumper that has integrated the diffuser style look.

http://www.jmautosports.com/duraflex...r/g-76477.aspx