best is very subjective especially when sound/looks comes into play.

I am very happy with my magnaflow catback although its more noise and looks than anything else. Another reason i like it is the fact that if i ever have a problem with it, the shop offers a 100% warranty on the exhaust system from rusting, leaking, etc. I wont have to ship it back either!

if you are going for power, a turboback will be the only answer since a catback is really a noise upgrade.

 

If i am allowed....i would like to introject some educational links for the group. It is very easy to get naturally aspirated exhaust theory mixed up with turbo exhaust theory.

Here are some simple links i found on the internet.



The Turbo Exhaust Response, Power & Reliability By MJ Ferrara

highlight: "a turbo exhaust system suffers no ill effects from going as big as possible. Bigger is better"



excerpts are from Jay Kavanaugh, a turbosystems engineer at Garret

highlights: "...the design of turbo exhaust systems runs counter to exhaust design for n/a vehicles...Downstream of the turbine (aka the turboback exhaust), you want the least backpressure possible. No ifs, ands, or buts. Stick a Hoover on the tailpipe if you can.The general rule of "larger is better" (to the point of diminishing returns) of turboback exhausts is valid."



By: Dennis Grant dg50@chrysler.com June 1997
Subject: Turbo Fundamentals.

highlight: "...Just bolt on a bigger, free flowing exhaust....in English, raise the turbo inlet pressure, lower the outlet pressure, or both, and you make more power"

The only drawback to a larger exhaust system are weight and sound. We have solved these issues with our muffler choice and by using 18awg stainless steel. So there is plenty of room in the market for systems of all shapes and sizes.



Jeff Perrin is also extremely educated on this stuff as he has to design some pretty complex exhaust systems for other vehicles. (Our Subaru STI exhaust system has a header, up-pipe, turbo inlet and exhaust housings (turbokits), front down-pipe, rear down-pipe and catback exhaust.) I will try to get him to post some good educational stuff.

 

Those are good references for turbo theory, but they don't address real-world exhaust system issues.

Here are the cons of larger diameter exhausts in practical applications:

• Routing - A larger diameter exhaust often forces additional bends, or sharper angles on bends to route to the rear of the car. Like most things on the MINI, the exhaust tunnel does not have heaps of extra room. The benefits of a larger pipe are quickly lost when it is less straight than a smaller pipe.
• Weight - Not a major consideration, but why make something weigh more than it needs to? You won't notice the extra weight on the dyno, but you will on the road.
• Sound - This has absolutely nothing to do with exhaust performance, but it's certainly a biggie for most people when it comes to selecting an exhaust. A low energy exhaust stream in a big pipe causes a muddy, droning sound. You then have to add resonators or resonance tubes to "dial out" the drone in most cases, and the resulting exhaust note is very weak and nondescript. The right sized pipe will have a crisp and clear tone that is easy to tune.

My only point of contention is that it has been claimed that anything less than 3" diameter is insufficient for the needs of a tuned R56. We found that the optimal diameter for the exhaust when factoring in the items mentioned above was 2.5" for cars making less than 300 HP. I'm sure when there are enough 300+ HP R56s out there, Way will offer a 3" version

 

You summed all that up nicely.

I have heard the same as well. When I go to a bigger turbo down the road though, 3" it is

 

LOL, me too. I'll keep the car STX legal as long as Matt wants to drive it, but at some point afterward once the aftermarket matures a bit, I'll probably try out a bigger turbo and exhaust, converting the car from stupid quick to ludicrous speed, scare myself, and take it all back off

 

Not true. You can have a great car and a bad driver and the car will have poor times and the same would apply with a poor car and top notch driver and will place with fastest times. You can have two identical tuned cars and the performance will still vary based on the driver. Does not matter how good the car is, it still depends on the driver (the human factor).

What would make the statement true is a top notch driver that can drive each car to its limit in an unbiased fashion.

 

we will never know.... the majority will never show up to find out

 

True.

 

I would agree with some of those things, but......
-Roughting. The new R56 allows for a very straight system, with very few bends. So 3" tubing fits with ZERO Issues.
to install ours, is a great benifit.
-Weight. This is important and i think adding 1.5lbs over the stock system when you install ours is exceptable. 39.2 lbs for the stock system, and our 3" system weighs 40.75lbs. This is with 2 EPA approved high flow cats, which are 49 stage legal.
-Sound. This is the most important one, which is not as much of an issue on the turbo car. The turbo "chops" up the sound waves and is quite to start with. But again, sound is all personal, if th3 2.5" systems suite one persons needs, then so be it. But we feel our 3" system is very mellow, and with virtually no one complaining of being too loud, and some actaully wanting it louder, we fee we are in a good spot.

Its seems like there are so many people stuck on Normally Aspriated engine theory. In these situations, the engine is having to pull in air, and push it out. So things like bends, size of tubing, volume of manifolds, ports, valve sizes, all come into play and greatly effect HP. But throw in a turbo, and things change.

These aren't things we are making up! 3" will make more power on a turbo car. Actually no exhaust on a turbo car will make more power!

 

That is something I would like to see, the flame would be wild, not sure the radiator and the rest of the front bar would like it though

 

+1 on this i wanted to pipe in earler but i was so drunk and i don't explain my self very well when i have been drinking. As proof i will let you install 3 in pipe on my cooper free of charge and i will take endless sound clips and dyno runs to prove all the old skool thinking wrong

 

Why is this so complicated? We have seen a before and after dyno comparison for the Alta cat-back. All we need is the equivalent data for the other exhausts. OK, I agree that results vary from car to car and depend on the environment so seeing then results for several cars would be better, but it seems pointless discussing the power of cat-backs when there are no results available. We need the test data!

 

well you're about 99% correct, but some turbo's exhaust housings actually spool up better with a bit of pipe coming off them. Porsche 993 & 996's are great for testing this as you can remove the rear bumper and run them open, with the exhaust, or with a megaphone/straight pipe

the only practical argument for smaller then 3" is personal preference for tone at the cost of some power. On the manufacturing end, it's much cheaper/easier to make a smaller diameter system...
Rmember, if you buy quality the first time, it only hurts once

If your only concern is the exhaust note & you're not looking to do any further modifications, then you really need to go to a Mini meet & listen to all the systems you're thinking about ... The videos on youtube SUCK, the audio is not consistent or even recorded w/ any similarity, plus some exhausts change tone a little after they've been 'broken in'....

I still laugh at myself for judging the Alta exhaust from the audio clips I found online, I'd even emailed them complaining they didn't have a sport version like Borla, I did a major re-evaluation after hearing the system on SimpsonGI's car & with nearly 5k on the TBE, I wouldn't go any louder. Taking it to the dyno in a couple hours

 

Here's the before (red) and after (blue) dyno for the WMW exhaust:




The day of the base run was much colder than the post-install run, but it still shows gains that were right in line with what I was expecting.

You should contact Way with any specific questions.

I'll be glad to discuss details about the system via PM with anyone who is interested, but I've grown weary of trying to correct some of the inaccuracies being posted in this thread. Like they say 'round these parts, I've got no dog in this hunt

Quite a few people got to hear and feel the power of the car via test rides at MOTD. This is definitely the best way to evaluate if an exhaust is right for you. The car will be at most of the southeast regional autocrosses, as many track days as I can possibly squeeze in, the SCCA nationals in Kansas, and the fall dragon, so please feel free to walk up and ask for a test listen or ride. It's a blacked-out PW with red viper stripes and black pin stripes, and will eventually have the personalized place SPUTNIK when the state gets around to stamping it

 

Well I had a crushing day at the dyno, back to back with a nearly identical R56 MCS, Greg/Boomer with the Militek 2.5" cat-back & myself with the Alta 3" turbo-back. Launched the exact same way with the same pre-run warm-up & everything, my Mini with the Alta TBE posted 5hp & 10ft/lbs less.
My numbers are so low I'm wondering if the '08's have some major mapping revisions, overboost eliminated, or maybe there's just a problem w/ my car
I suspect I'll be throwing on the stock exhaust next week & taking it back to the dyno &/or the dealer...

 

Hmm....maybe 2.5" FTW??

Honestly though, maybe he just has a stronger one. The R53's had huge variences when dynod. Also, it looks like your car was not in overboost at all, considering there are stock R56's putting out near 200 ft-lbs to the wheels while in overboost.

 

it's entirely possible mine isn't going into overboost, I've never been able to tell the difference between rolling into WOT & mashing the pedal WOT, I think the Alta's a very well designed & executed product and the theory is sound, but my results were really disappointing

 

Another person posted their dyno results and they had the Alta Boost Tubes, Alta Catback and Alta Intake and made just under 5HP. Burger Tuning discovered when he put a custom intake and exhaust on his test R56 he was unable to make any power gains. When he reported the rusults many people rudely disputed his testing. The guy has made some wicked 400 + HP 335i BMW's but people told him he must have been doing something wrong. Nothing against Alta but it looks like the 15 HP horsepower that the JCW stage 1 kit made was about as good as this car is going to get unless you want to deal with Check engine lights, high intake temps, and inconsistent power gains and even then you will only make 20HP max.

With that said an Alta Intake and Catback look and sound good. I ran my car at the dragstrip many times and had some inconsistency. But I was able to get 2 passes completely stock with a 2.2 60ft both times and I have a 6 speed Auto and both clean passes were between 14.8 and 14.9 at 91 and 92 MPH. When I went back to the same track (CA Speedway Dragstrip) last week with my Alta stuff it was about 5 degrees warmer and I still ran a 2.2 60ft but I only ran 14.9 best. As I suspected by my butt dyno the car sounded cooler but is not any faster.You may gain a little from 5000 to 6000 RPM's but you give it back from 2500 to 3500. I am confident as the weather gets warmer the car will be slower than stock with the intake on.

People want to believe when they spend 1000.00 dollars they will automatically get 20 HP but some of the new cars out there like the R56 is so efficient from the Factory it is difficult to make gains with just bolt ons. I new this and never expected 20 HP out of my Alta Intake and Exhaust so I am not upset but I could understand if some people were. I do think the Alta stuff improved my Peak HP about 5HP maybe a little more especially when it is cold outside.

I wish more people would run there cars stock at the track bolt on the parts and then run them again. This is a good way to test parts as long as it is the same track and nearly the same weather conditions. Nobody should argue that you can't get accurate results because the same pass cannot be replicated. We are driving slow 14 second cars and a good bracket racer could run within 1 tenth in these mini's 10 times in a row. The argument does work if you are testing a 400 HP car on a street tire.

 

Derosi has just said everything SO WELL.

I second everything you said.

 

If you get on the throttle pretty hard, say bout 90% and then floor it completely, you will feel the overboost kick in. Maybe its just me, but I can feel it everytime. When I had my K&N clamped directly to the MAF you could hear the difference as well. (In the turbo)

 

ALTA turbo back exhaust....'nuff said.

 

These kinds of posts are just silly. There's no quantifiable data in here. In light of all the actual information posted in here this kind of post just has no real value.

 

an old Ford Ranger almost smoked me recently despite my happy meal of intake and turbo back exhaust modifications. I have lots of noise but the car is a much better handler than straight line performer.

 

Jeff and I will see what we can do. Maybe on the mule at the next MINI event. But the gain will be there for sure!

 

Well good news and bad news. Good news, don't stress too much about the dyno results. Bad news, sorry the dyno results weren't more to your liking.

Couple things: The P0420 code doesn't affect performance. So leaving it in play is a-ok.

Did you "reset" the ECU prior to making the dyno runs? If so, the car/ECU takes about 10 passes to even build the boost back into the car. So you would be down on power for far more runs than were taken.

Also, the R56 is a totally different beast to dyno vs. the R53. The way you get to the power, the gear you make the run in etc. ALL play a HUGE difference in how things go.

Did you have a boost gauge installed? What were the boost levels?

What fuel choice did you have? What was the other car running?

My point is, that we can certainly discuss the how's and why, but the fact is the car would outperform a similarly equipped car without a TBE.

We welcome the opportunity to speak to you via phone on Monday.

Thanks again for choosing ALTA!

Adam