Hello fellow members,
I haven't really seen any threads about how to install the Difflow diffuser onto a car with the Seibon 2002+ rear valence.
The problem with this is that it doesn't fit like the typical OEM 2002+ rear valence. For one thing, the Seibon is too stubby in the bottom part where the diffuser would have mounted, so it will not reach. The second issue is that the Seibon bottom part is too flimsy. It flexes so much, and is held by two bolts to the rest of the rear valence that I feel the diffuser would be ineffective in providing the whole car the intentioned rear downforce. I think if it was to be mounted to that bottom piece, it would continuously flop up and down as the car is driving at high speed, and eventually rip off the Seibon bottom part.
I have no issue with the Seibon being light and flimsy, as it reduces weight (more so than the OEM rear valence), and it was not designed to support the weight of anything else.
I knew I had to figure out an alternative solution to mounting it.
I came up with a bar that the Difflow would mount onto. The front part of the diffuser still mounts in the same place, but I designed a bar that would attach to the chassis so that when the diffuser was going at fast enough speeds to create downforce, it would do so straight to the chassis of the car.
I went to Lowes, and found the section where they sell various bars. I looked specifically in the aluminum section for light weight, and found a 72" L-shaped bar. Cost= under $15.
I measured it to the diffuser, and cut it to the same width of it (approximately 39") using a dremel and cutting discs.
I then looked for a place to mount it on the body of the car. Looking around the area of the exhaust, I found two bolts on the chassis that I could attach the arms. I measured it down to approximately where the diffuser would go. It was around 8". I then cut two 8" pieces of the L-shaped bar. I drilled two holes where I could thread screws with bolts to the long L-shaped bar (I think around 36" apart), as well as holes on each end of the two 8" bars.
I unthreaded the two nuts from the chassis, and attached the 8" bars vertically through each of the top holes.
Then I attached the long bar to the two short bars using bolts and nuts.
I loosened the allen screws on the Difflow for the rear mounts to the very end of the threads without letting the screws fall out. I attached the front of the diffuser to the appropriate place (according to the Difflow instructions) and attached the locking bar immediately afterwards (counter to the Difflow instructions which state to do this last). This is because my bar was still angled a bit too far forward towards the front of the car. The aluminum bars have just enough "give" that they can be bent backwards once the front part of the diffuser is attached.
I then kept the diffuser propped up with my shoes while I used a long standard screwdriver to open/lift up the rear "flaps" of the Difflow, while at the same time using my other arm to pull back the L-shaped bar so that I can slip it under the flap. Once I was able to do this, I went to the other side and did the same. I tightened up the allen screws from the middle of the car and worked myself outwards, so that the diffuser would not bow.
I am very satisfied with the install. My diffuser sits just a few millimeters below my Seibon bottom part without ever touching it. No matter how much I try to move around the Difflow, it is pretty much immoveable. I know this will be more effective than mounting it to a rear valence.
I reversed the bolts, and then cut them short.
I hope this helps others who have the Seibon rear valence, or OEM owners who don't want the Difflow to make contact with their diffusers, or those who want a much better mount to the structure of the NSX.
I haven't really seen any threads about how to install the Difflow diffuser onto a car with the Seibon 2002+ rear valence.
The problem with this is that it doesn't fit like the typical OEM 2002+ rear valence. For one thing, the Seibon is too stubby in the bottom part where the diffuser would have mounted, so it will not reach. The second issue is that the Seibon bottom part is too flimsy. It flexes so much, and is held by two bolts to the rest of the rear valence that I feel the diffuser would be ineffective in providing the whole car the intentioned rear downforce. I think if it was to be mounted to that bottom piece, it would continuously flop up and down as the car is driving at high speed, and eventually rip off the Seibon bottom part.
I have no issue with the Seibon being light and flimsy, as it reduces weight (more so than the OEM rear valence), and it was not designed to support the weight of anything else.
I knew I had to figure out an alternative solution to mounting it.
I came up with a bar that the Difflow would mount onto. The front part of the diffuser still mounts in the same place, but I designed a bar that would attach to the chassis so that when the diffuser was going at fast enough speeds to create downforce, it would do so straight to the chassis of the car.
I went to Lowes, and found the section where they sell various bars. I looked specifically in the aluminum section for light weight, and found a 72" L-shaped bar. Cost= under $15.
I measured it to the diffuser, and cut it to the same width of it (approximately 39") using a dremel and cutting discs.
I then looked for a place to mount it on the body of the car. Looking around the area of the exhaust, I found two bolts on the chassis that I could attach the arms. I measured it down to approximately where the diffuser would go. It was around 8". I then cut two 8" pieces of the L-shaped bar. I drilled two holes where I could thread screws with bolts to the long L-shaped bar (I think around 36" apart), as well as holes on each end of the two 8" bars.
I unthreaded the two nuts from the chassis, and attached the 8" bars vertically through each of the top holes.
Then I attached the long bar to the two short bars using bolts and nuts.
I loosened the allen screws on the Difflow for the rear mounts to the very end of the threads without letting the screws fall out. I attached the front of the diffuser to the appropriate place (according to the Difflow instructions) and attached the locking bar immediately afterwards (counter to the Difflow instructions which state to do this last). This is because my bar was still angled a bit too far forward towards the front of the car. The aluminum bars have just enough "give" that they can be bent backwards once the front part of the diffuser is attached.
I then kept the diffuser propped up with my shoes while I used a long standard screwdriver to open/lift up the rear "flaps" of the Difflow, while at the same time using my other arm to pull back the L-shaped bar so that I can slip it under the flap. Once I was able to do this, I went to the other side and did the same. I tightened up the allen screws from the middle of the car and worked myself outwards, so that the diffuser would not bow.
I am very satisfied with the install. My diffuser sits just a few millimeters below my Seibon bottom part without ever touching it. No matter how much I try to move around the Difflow, it is pretty much immoveable. I know this will be more effective than mounting it to a rear valence.
I reversed the bolts, and then cut them short.
I hope this helps others who have the Seibon rear valence, or OEM owners who don't want the Difflow to make contact with their diffusers, or those who want a much better mount to the structure of the NSX.
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