LeadToRome

Is there any actual CFM data available for stock and any of the aftermarket exhausts? I always hear people talking about the benefits of free flow exhausts but I wonder how much more air can actually flow. Just looking at it, the stock exhaust doesn't look all that constrictive, it looks like the headers would be the biggest impediment to breathing. Of course what it looks like to me and what actually is happening are quite possibly two very different things.

Is there any actual data? CFM data under test conditions and as-installed would be very useful, I'm not sure I can justify dropping a grand or three just to make the beast sound better when stealth and actual performance are what I'm after.

rktskicar

the flow benefits of an exhaust are best seen by looking at the dyno WHP gains from the exhaust. for this car, you are not going to get much WHP benefit (5-6 WHP). Most the change with an exhaust is the sound.

Bruce

BaLLZDeePNYC

The sounds is intoxicating lol especially in tunnels. And the butt dyno makes you feel like significant gains are made due to a nice amount of increased torque depending on the exhaust you get.

Jeembo

You got your exhaust already? Gotta check it out some day.

REMUS4myAudi

LeadToRome: REMUS USA Rep' responding. We have some data on back pressure reductions from our free flow exhausts, but I will have to have REMUS Austria re-send that doc' as ours was lost in our last comp'r issue. But from what I remember, typically our back pressure reductions are in the 60% (Sports Label - quieter) all the way to 80% (U.S. Sound / Race - louder). Back pressure reductions cannot just be arbitrary; it is precisely engineered at REMUS so that the boost in power is in a useable range. Most of our systems give a boost in mid-range r.p.m., where it can be utilized the most. A few of our "U.S. Sound / Race" systems give Top End boosts, but for the most part, REMUS tries to go for mid range increases through back pressure reductions. Sound absorption back pressure is as close to a straight pipe as can be, but that slight slowing of the exhaust gases at the RS (Rear Silencer) is significant to increased power characteristics. Yes, equal length headers are a great benefit to free flow. When the power pulses come in to the merge down pipe, timed around each other, instead of on top of each other, flow is greatly enhanced. Headers w/ free flow exhaust can double power increases over just RS or FS (Front Silencer) changes or deletes.

And speaking of "stealth"... One of the true statements that REMUS lives by and has helped them become the world leader in O.E.M. and aftermarket sport exhaust is: "All the H.P., torque and efficiency benefits of engineered back pressure free flow exhaust, without all the racket."

I hope this helps.