Difference between downpipes?

[M4FOREVER]

Another question which one gives more power? Down Pipe or charge Pipe?

[Modified_f80]

Originally Posted by M4FOREVER

New to the tuning world. Would a downpipe alone make a difference in performance. F80 zcp.

You will need a tune with that downpipe to gain full benefits.

So to answer to your question, yes it will make a difference but you will want to get tune for it.
There was a post somewhere here where they installed the downpipe without the tune and saw performance gains.

You will get a check engine light due to the downpipe.

[tom @ eas]

Originally Posted by M4FOREVER

Another question which one gives more power? Down Pipe or charge Pipe?

No gains to be had from charge pipes, just stronger than the plastic counterparts while running increased boost.

[TurboSid]

ER is the best.

Also I have ER for sale

[Tiago@VRSF]

We have a few thousand satisfied customers with our S55 downpipes. The last thing you'd want to do is gamble on a no name brand and get stuck with a $2-400 labor charge to have to re-install your OEM downpipes

[DanMpower]

So for I've run Active Autowerke downpipes and am currently using Akrapovic downpipes.

I chose these two because of the flex joints they incorporate, didn't want to add any extra stress on my turbos/manifolds, etc. Surprisingly there is actually a sound difference between the two, I was expecting downpipes to all sound the same but this is definitely not the case.

The AA downpipes were definitely raspier for most of the powerband, the Akra downpipes still have rasp but a lot less pronounced and only at higher RPMs, they also sound deeper. I'm thinking maybe because of the heatshield the Akras come with that helps with the rasp and tone.

Fitment with the AA was excellent but the Akrapovic is perfection, it could easily pass as an OEM piece. I actually enjoyed installing the Akras since everything just slid into place and lined up with amazing precision.

If you guys can swing the extra $$$, definitely go with Akrapovic, I'm extremely pleased with the power/sound/fitment/quality.

[Tiago@VRSF]

The flex section vs no flex section has been beat to death. There are thousands of downpipes without the expansion bellows as they're properly referred to as and it's been proven that they offer absolutely zero benefit over downpipes without them.

[RevNev]

Originally Posted by Tiago@VRSF

The flex section vs no flex section has been beat to death. There are thousands of downpipes without the expansion bellows as they're properly referred to as and it's been proven that they offer absolutely zero benefit over downpipes without them.

Did BMW fit the "expansion bellows" that Akrapovic adopted to unnecessarily increase production costs?

[blockdoc]

Originally Posted by RevNev

Did BMW fit the "expansion bellows" that Akrapovic adopted to unnecessarily increase production costs?

Tiago is right. There have been multiple threads about this. The short answer is....ask Akra. Who knows?

[SflBimmer8484]

We continue use the flex to combat vibrations, reduce stress / fatigue and it helps a lot with installation of aftermarket exhaust systems since it can adjust to any angle. We have installed every brand of downpipe at this point and none go on easier and sit as flush as the pipes with a good flex.