Just talked to my exhaust guy. I'm looking to get a custom exhaust because I don't feel like paying nearly 500 for Magnaflow's. He said he would add slightly larger piping and a new muffler. He said I would gain about 5% more power and a little low end noise. The parts + labor for 125. What do you guys think? The money is right but is 5% more power worth the trouble? What are you all's experience with custom exhausts?

Thanks.

 

I don't think you will get 5% HP increase. There just is not enough restriction to get that much benefit. If you want a better sound $125 is not bad if you know what you are getting.
I did the 'one ball' for about $50 and am very happy with the change and cost.

 

The one ball would be awesome but I have a non-s. :(

 

You're not likely to get 5% doing that. Hp and tq performance are not easy to improve on the Cooper. In fact, some will say that with wider pipes you're more likely to lose tq than gain hp. Not all, but some. If you noodle your way through all the theories this actually makes sense, but only as a generalization. A well-designed exhaust can improve hp and/or tq to some degree though, and if you and/or your tech understand the MINI engine/exhaust system well, you can net gains via exhaust work alone, but you normally only find claims anywhere near 5% in the fantasy world of the product press release.

To realistically get as far as 5% and beyond you almost have to start with head work and make sure your manifold and exhaust work well with the head.

I'm not suggesting it's all or nothing though. The primary benefit of doing just the exhaust on a Cooper is improving the sensory experience. Yep, that's just a fancy way of saying making it sound better (or, more importantly, to your liking), but driving the MINI is fun because of the overall sensory experience anyway and I like to think of choosing the right exhaust note as just a part of that whole.

If you're obsessive about these things (like me) you can go way too far trying to make it sound "just right." I've spent too much time and money trying to get exactly what I want. In fact, I'm on my 5th post-stock exhaust. I was in love with the latest -- perfect (for me) sound quality and quantity -- and then I did the manifold..... Now it still sounds fantastic but it's louder than I wanted it to be. Ah, unexpected consequences, but then that's half the fun for some of us.....make a change, see what happens, move on.

If you decide to go ahead with the custom exhaust, here is something to consider. One positive aspect of the stock sytem is there's no in-cabin resonance boom. Some people call this drone, but I think those people haven't really felt the pressure on your skull you get from a sympathetic cabin resonance. Seems like most aftermarket replacements cause some level of highway drone and it's up to the individual to decide whether it's bothersome or even noticeable. I've had this problem a few times with systems that came with only a rear muffler and managed to improve each (to differing degrees) by adding another cylindrical muffler or resonator in the space just aft of the cat flange.

fwiw

 

5% NO
Maybe Better Sound

 

To be honest, I'm not too concerned with the tone right now. The factory tone is fine with me. I am more concerned about power. So a custom exhaust is not the way to go? Would that magnaflow be worth the price then?

Thanks for the replies!

 

That 5% is hard to get. You can get a Megan Racing for $380. But don't count on getting big power from the exhaust. We found more gains with the intake and tune.

 

I got a Magnaflow for my Cooper off of http://www.performancepeddler.com/
It kind of looks like a fly by night kind of website, but I called 'em up and talked to a guy who was really helpful. I ended up paying $350 ish for mine during a XMAS sale, but they will still beat any other place for Magnaflow prices.

For me the sound is amazing. I love it.
The HP boost is barely noticeable.

 

5% is a lot of power... your talking about 10 to 15 HP with 5%. Your not likely to get those kinds of gains with just an exhaust. If your looking for power gains, it's better to get headers instead. Exhaust is mostly for sound...

 

5% on a Cooper is about 6 hp.

 

I installed a Megan Racing exhaust this spring. The main reason I did was because the OEM, with about 103,000 miles on it at the time, was rusted out, and had been trussed up with mechanics wire.

Reasons I went with the Megan was mostly price, and my buddy Way sells them. I don't think there was any real gain in HP, but I sure do love the sound of it, and it seems to be a perfect match with the Way/DDM intake. There is some cabin drone, which I don't mind, plus the iPod gets rid of it if I want

OEM




Megan


Mark

 

That is the EXACT scenario we went through about a month ago with my girlfriend's MINI. on the fit, finish and sound of the Megan setup!

 

Thanks a lot for the pics lotsie. I think I'll save my money for a Megan and some headers. I'll just run a stock exhaust for now. Thanks again.

 

I have the magnaflow too and love it, they are cheaper on ebay but I wanted a warranty(salt in winter kills an exhaust) so I got it here. magnaflow 16662, or you can try one of the vendors