Hello all,
I was reading that the stock exhaust has a variable flow rate. At low speeds/rpms the flow rate if 130 liters/minute. At about 4,000 rpm the exhaust pressure builds up enough so that an exhaust valve opens up allowing 150 liters/minute of flow.

I thought this was a very well designed feature by Acura!

So my question goes out to all the other Horsepower Motorheads (like myself) on this forum who own an RL (a luxury touring car) who secretly want to turn it into more of a Sport Luxury Touring car:

What is the advantage of adding an aftermarket exhaust compared to the high flow rate of the stock exhaust?
What is the flow rate of the 5-Zigen exhaust (which seems to be the most popular one)?
Do any of the aftermarket exhausts have pressure sensitive exhaust valve openings? Mugen? Tanabe? Fujitsubo?
And 1 other practical question, could you describe any exhaust drone noticeable with your aftermarket exhaust.

Thanks all in advance.
Peace.

 

There have been 2 dynos with the AEM CAI and the 5Zigen exhaust that yielded about 13 hp (https://acurazine.com/forums/2g-rl-2005-2012-76/m-003-my-rl-dynoed-part-2-post-mod-results-videos-pix-499256/). I think that has more to do with the exhaust than the intake, but we won't know for sure until more people dyno before and after.

I would imagine the aftermarket exhausts always use a higher flow rate to increase performance, but I don't know enough about exhausts to confirm this.

The Fujitsubo setup is actually quieter than stock, 2 dB according to rip-you-off-Touge.

 

Does anyone know was the db for 5zigen exhaust vs stock one. I can't recall and 5zigen site has been updated without that information.

 

Hello,
I'd like to hear back from all the owners that have put in aftermarket exhausts.
Sometimes with exhausts it sounds just right, sporty, not too loud, and most inportantly no exhaust drone.
But other times it sounds sporty, but there's the Very Annoying exhaust drone at certain rpm ranges.
The thing that I like about the stock exhaust is the pressure sensitive exhaust valve which is closed at low rpms and subsequently No exhaust drone!
I'm interested in an aftermarket, but the Fear of Annoying Drone is preventing me from this mod.

 

Most of the exhausts out there for this car dont touch the exhaust valve you speak of as they are not full exhausts.