Are they both really useful? I heard they are actually rear diffusers?? Are they?? Any one have pics of the bottom of the bumper???? Thanks!

 

The Acura A-Spec bumper is just cosmetic. The "diffuser" is simply an area which has been plainted flat black. It serves no functional purpose and won't reduce wind drag anymore then a regular bumper. Can't speak about the Mugen bumper. Maybe someone else can jump in.

 

The A-Spec package overall was made to reduce the Cd in the RL, and initially Acura marketed it that way. Now they don't market it at all. Whether the typical driver of the RL (e.g. not us enthusiasts) notices any difference in daily driving with or without the kit is another story altogether.

There's a built-in rear air diffuser under the car. If you look under the center of the bumper, you'll see it.

 

I learned something today. Didn't know it had an air diffuser under the chassis. Thanks Bob

Is that on all RL's or just those fitted with the A-Spec package? The A-Spec bumper doesn't play any functional role in collecting or channeling air. I know that much because I have it on my RL. However, I didn't get the full A-Spec kit including suspension and wheel parts.

By the way, how's the weather up there today? Heard it's nasty for the primary voting. Do your duty and get out and vote with your SHAWD RL

 

I am sure you have probably seen this video, but it gives some interesting views of the underside of the RL and the various aero devices under the chassis.
http://www.vtec.net/articles/view-ar...icle_id=452729

 

Yes I did see that once long ago. I just watched it again. The OP should watch it. Probably answers most of his questions

 

Yup, I voted first thing this AM. I vote in even the most mundane municipal election. After all, freedom isn't free, it comes with responsibility! /soapbox Not to mention, I enjoy possibly having a role in our country's history.

The rear diffuser is present in all RLs. I learned about it from that TOV video, in fact. Our car is so wonderfully engineered, even underneath. It even has little wings by the wheels.

 

Yes and it kill me that no one knows and thinks it is an Accord. Of course, just show someone the flush windows, and immediately, they know this car is something different.

 

I knew about the diffuser, didn't know about the wheels thing...

 

any one with a mugen one????

 

So everyone that saw the video, it said if you get an after market header it will add hp. How come know one makes one for our cars??

 

There's not a large enough market for headers, for starters.