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FD3S: RE-Amemiya Rear "Street" Diffuser. New mold* Slightly redesigned.
Hey Guys,
Just wanted to give an update. Sometime early in the year (2017) we decided to improve fitment and create a new mold for the street diffuser, so it is less hassle for any potential customer trying to figure out the best way to install this. We added more material in common problem areas and redesigned the passenger side of the rear diffuser so it covers more area. Less chance of having gap issues with the new version.
Some people found the old version or authentic RE-Amemiya version a bit tricky to fit in a way to minimize the gaps. We simply redesigned it so there's less to figure out.
There is an old thread on the street diffuser if anyone wants to check it out:
Received my new better fitting FD rear diffuser back in March. Waited for spring weather to arrive before installing it.
Then waited for warm weather to paint it satin black. It is installed with with black zinc phosphate screws.
It looks nice except the two areas of poor fit????
i have the same RB muffler and have the same issue. emailed Ken and this is what he communicated.
"Those are the transition points which are a bit tricky. It doesn (not sure if ken meant to say does or doesn't) require some 3m double sided tape.
For the left side, you can hand sand the edge of the area of the diffuser before it transitions in. However, you have to be careful not to sand too much. I would do 1mm at a time.
For the right side, I would try one more screw directly right above the muffle where there is sort of a "bridge" on the diffuser. That part has no mounting support, so another screw there definitely helps. I would try a little bit more sanding on the transition point for the right side. Take off 1mm at a time. Once enough material is taken off, it should sit right where it needs to be."
I didn't bother with it and left as is.
Let me know if you decide to fix and how you fixed it.
im running into an issue where it seems like when the diffuser is attached to the mounting points in front of the gas tank the left side of the diffuser dont want to sit in correctly. I may just cut it off straight across where it moutns to the gas tank standoffs and get the fender sides sitting nice, then attach it via metal straps or something. if that makes sense lol. I did remove my gas tank awhile ago, maybe the straps aren't in the oem placement exactly, maybe that could be it?
To properly install the RE-Amemiya Street Diffuser, you will need to put self-tapping screws in these key areas along with 3M double-sided tape along the outer edge to get the diffuser to sit flush with the rear bumper (we didn't even use double-sided tape this demonstration). Why? Because this is an awkward transition point where the diffuser starts from inside and then goes outside. The OEM plastic piece only sits on the inside, so it does not have this issue. The street diffuser requires a bit more creativity. If you do not place screws in these areas, there is nothing holding the diffuser up at those points. The old version diffuser was installed in this manner as well. No changes to the way this is supposed to be installed. We only added more material in key areas so there is less likelihood of the diffuser looking like it is drooping down. Any locals wish to drop by for a live demonstration on our test fit car, hit us up!
Now we offer a flexible carbon version, which should help further with installation.
Last edited by shineautoproject; Sep 7, 2018 at 06:54 PM.
