[Ezrollerr]

I have purchased AR design downpipes for my 335xi.
I also have JB4 and dual cones.

I am wondering if purchasing a BMW genuine performance exhaust will make a difference other than sound or extra few horses for the money that I might dish out?

Thanks

[BEAR-AvHistory]

You already have the key exhaust component with the DP's. BMW exhaust is a very poor buy for a performance increase.

[E90Company]

No it won't add any performance at all, and your car will sound like crap with the PE and DP's.

[supahdave]

Sound is subjective. I had ar dps and pe on my car and it sounded better than any hks, vanguard etc i heard in my opinion.

[Ezrollerr]

Thanks folks.. I guess what I am trying to justify is that is 800 bones going to add any more value in terms of performance or not?

It seems that not much ..

[Eric335]

With catless DPs it will be rather raspy....

[Javier]

No you will not see a performance gain from the PE, since it still retains the secondary catalytic converters. (unless you cut those out)

Also, general consensus on this forum is that the PE doesn't sound very good with Cat-less downpipes.

[e92oholic]

Originally Posted by Javier

No you will not see a performance gain from the PE, since it still retains the secondary catalytic converters. (unless you cut those out)

Also, general consensus on this forum is that the PE doesn't sound very good with Cat-less downpipes.

I've heard it with catless dp's and it sounds awesome.

[E90Company]

Originally Posted by e60oholic

I've heard it with catless dp's and it sounds awesome.

If you like rasp it sounds good

[BEAR-AvHistory]

Originally Posted by e60oholic

I've heard it with catless dp's and it sounds awesome.

Sounds like a wannaB fart can.

[e92oholic]

Originally Posted by BEAR-AvHistory

Sounds like a wannaB fart can.

Um not at all.

[parky1215]

Bmw pe will sound like cheap honda tin can sound exhaust with catless dp when rpm goes over 5k.

[PR3CI5N]

People can say it doesn't add any power but it does from 5500k to red line. The car feels like it can breathe better. Obviously the PE doesn't add 20-30 whp but the power difference is noticeable. I didn't buy my PE for the performance though, I bought it for the sound. I bought my DP's for performance. I bought my PE used for $800 off a member on here so as long as you find a good deal I think the PE is well worth it.

[idrift4wd]

Originally Posted by PR3CI5N

People can say it doesn't add any power but it does from 5500k to red line. The car feels like it can breathe better. Obviously the PE doesn't add 20-30 whp but the power difference is noticeable. I didn't buy my PE for the performance though, I bought it for the sound. I bought my DP's for performance. I bought my PE used for $800 off a member on here so as long as you find a good deal I think the PE is well worth it.

Just think about it this way. PE are just mufflers. all the way at the end of the exhaust. Its very hard to see how the engine itself can make more power with a different muffler. Axle-back exhaust tend to just change the note of the engine and allows for slightly better exhaust flow, but its to a small point where the engine itself cant see the benefits of it. all cars technically dont need back pressure. Only reason they are there is to make sure your car abides by the law. Your car can sound really good, but make the same amount of hp. On a good day, you'll see 1-2 HP to the wheels. so maybe 3-4hp to the crank.

But its a great exhaust, the exhaust note is great but dont expect much HP.

[jetbill]

What might one expect if they had stock downpipes with secondaries deleted and the PE?

I've been tempting to just try it and worse case put some resonator inplace.

[Fully_Bolted]

Originally Posted by jetbill

What might one expect if they had stock downpipes with secondaries deleted and the PE?

I've been tempting to just try it and worse case put some resonator inplace.

It will sound great as long as you have catted downpipes.

[BEAR-AvHistory]

Originally Posted by PR3CI5N

People can say it doesn't add any power but it does from 5500k to red line. The car feels like it can breathe better. Obviously the PE doesn't add 20-30 whp but the power difference is noticeable. I didn't buy my PE for the performance though, I bought it for the sound. I bought my DP's for performance. I bought my PE used for $800 off a member on here so as long as you find a good deal I think the PE is well worth it.

Its not just people who say that its what BMW says, they list max gain of 8 crank horsepower at top end. $100 for 6.8 wheel horsepower for a few hundred RPM is not a very good deal. With a normal system they can make a nice sound but they are of no real value in generating any usable power.

Also the 335 is pretty much all done in by 6300rpm based on any twin turbo dyno runs I have done or seen. In fact the default JB4 shift light setting is at 6K & is what the development cars are shifted at.

[PR3CI5N]

Actually my BMW PE replaces the midpipes which contains resonators so its a little more than just a "muffler" system. Guarantee with my mods my exhaust added 10+hp

Originally Posted by idrift4wd

Just think about it this way. PE are just mufflers. all the way at the end of the exhaust. Its very hard to see how the engine itself can make more power with a different muffler. Axle-back exhaust tend to just change the note of the engine and allows for slightly better exhaust flow, but its to a small point where the engine itself cant see the benefits of it. all cars technically dont need back pressure. Only reason they are there is to make sure your car abides by the law. Your car can sound really good, but make the same amount of hp. On a good day, you'll see 1-2 HP to the wheels. so maybe 3-4hp to the crank.

But its a great exhaust, the exhaust note is great but dont expect much HP.

[Fully_Bolted]

Originally Posted by PR3CI5N

Actually my BMW PE replaces the midpipes which contains resonators so its a little more than just a "muffler" system. Guarantee with my mods my exhaust added 10+hp

Thats a good point. BMW PE for the sedan is downpipe back i believe. For the Coupe its axle back.

For my E92, I have catless downpipes, stock midpipes with cats deleted and replaced with resonators. I think it sounds "OK" in terms of raspiness, but it sounds mean as F*CK when WOT. Just got my mini USB to 3.5mm adapter for the Go Pro, so i can run an external mic. If anyone is interested in hearing what this combo sounds like i can take some vids, or if you want to see the flames it shoots when I NLS from 4th-5th

[BEAR-AvHistory]

Here is what BMW says:

"The BMW Performance exhaust system invigorates engine output by allowing engine by-products to exit the vehicle more efficiently. RPM performance is heightened and engine performance is increased by up to 5hp and 3 ft-lbs"

Key words are UP TO which suggests best case. Since BMW posts all it power numbers at the crank not the wheel the exhaust does not do squat for performance but it does sound good.

Anyone who believes BMW is in error with their numbers should post before & after dyno runs.

[ken1137]

Hp gain with any exhaust is negligible. You already have DPs & JB4 and sound is very subjective as most have posted. I have AR catted DPs with the BMW 335is exhaust...I like the sound. The best sound IMO is Berk (axle & mid) with ARs, but they dont make an exhaust for the 335. GL

[Fully_Bolted]

Originally Posted by BEAR-AvHistory

Here is what BMW says:

"The BMW Performance exhaust system invigorates engine output by allowing engine by-products to exit the vehicle more efficiently. RPM performance is heightened and engine performance is increased by up to 5hp and 3 ft-lbs"

Key words are UP TO which suggests best case. Since BMW posts all it power numbers at the crank not the wheel the exhaust does not do squat for performance but it does sound good.

Anyone who believes BMW is in error with their numbers should post before & after dyno runs.

I wont say that the PE will give you a big jump in power, but its also important to note that BMW's specs are given for a stock vehicle. If you factor in the removal of the factory cats in the DP's, along with a tune that runs much higher boost (larger volume of exhaust), you can see that anything that will create less backpressure is going to improve power. Given that the PE is basically straight through, i wouldnt be suprised to see a gain of atleast 5 whp on a FBO car. Paired with a midpipe cat delete, maybe 10-15whp. Just speculation though, i have no dyno comparison.