[AudiM3]

I agree with Obioban. I just had my SS stepped headers installed a couple of weeks ago. It was way easier to put the SS headers on then taking the OEM's off. And as far as fitment goes its EXACTLY like stock. I used OEM gaskets, OEM bolts, and OEM nuts. And there was no fuss trying to align the holes.

[ravfox]

I can confirm the opinion of those saying the fitment on the SS v2 stepped is superb, and that they are easier to get on than stock is to get off. The Euros simply cannot be any better than the SS. Incidentally, I have essentially the same exhaust system - SS V2, Custom Perf. sect 1 with 200 cell cats and stock Sect 2 and muffler. Sounds nice, lower timbre, but thankfully no louder than stock, driveability noticeably improved. The evovleR tune is the cherry on top. I am very satisfied and will likely do the identical mod to another car.

[Dan Rodriguez]

I don't know which are better...I would guess the SS performance-wise. But I have to point out that just because something goes on easier than it comes off does not mean it fits better. My ///M3AN ONE headers went on easier than the stock ones came off. But that was due primarily to the cats getting in the way on the stock headers and the raised lips around the 18 nuts that secure the headers to the engine. But I would never argue that the ///M3AN ONE headers fit better than the OEM ones.

[Obioban]

A note on the power difference:
The stock euro car is rated at 343bhp, the US cars are rated at 333hp. Of that, 4 of the horsepower are due to the different horsepower rating systems (bhp vs hp-- apparently european horses are weaker than american horses), which means the euro headers, per BMW, are worth 6 crank horsepower.

Most people who go with SS headers gain about 20whp, which equates to about 25 crank horse power.

Food for thought.

[SupersprintNA]

Originally Posted by Obioban

A note on the power difference:
The stock euro car is rated at 343bhp, the US cars are rated at 333hp. Of that, 4 of the horsepower are due to the different horsepower rating systems (bhp vs hp-- apparently european horses are weaker than american horses), which means the euro headers, per BMW, are worth 6 crank horsepower.

Most people who go with SS headers gain about 20whp, which equates to about 25 crank horse power.

Food for thought.

Couldn't have said it better myself. Thanks Ian.


Seems like this debate comes every so often. Each time I find myself wondering the same string of logic based questions:

Where (and why) are all these used Euro headers coming from?

What are the Euro guys installing to replace their OE headers?

Would they buy a header that only performs "the same" as what they already have?

Would you?



The bottom line is this, and Ian already said it. The Euro guys pull their headers off for the same reason we do, to get better performance. What do they install?


Supersprint.

[OldFanatic]

thank you for your post, since you are here and no body else but Supersprint should have a better dyno graph of their own product. Will you please post or link us to it.

[flipm3]

Here are all the dyno graphs from Supersprint's Website. Keep in mind, it looks like they use the extremely accurate MAHA Dyno.

Link: http://www.supersprint.com/en/prod-p..._lhd__rhd.aspx


European E46 M3 with stock Euro Headers, SS cats, XPipe, and Race Muffler
341.4hp at 7050RPM


European E46 M3 with SS Stepped Headers, SPipe with cats, XPipe, and Race Muffler
352.7hp at 7945RPM

So you can see that the only differentiating factor are the upgrade to the SS Stepped Headers. Notice that there is a gain of 11whp at max power.

[flipm3]

Here's a good dyno showing an all else stock Euro M3 compared to a M3 with SS Stepped Headers, SPipe with cats, XPipe, and Race Muffler.

[bimmerfan08]

Originally Posted by Obioban

A note on the power difference:
The stock euro car is rated at 343bhp, the US cars are rated at 333hp. Of that, 4 of the horsepower are due to the different horsepower rating systems (bhp vs hp-- apparently european horses are weaker than american horses), which means the euro headers, per BMW, are worth 6 crank horsepower.

Most people who go with SS headers gain about 20whp, which equates to about 25 crank horse power.

Food for thought.

Euro M3s also have cats in section 1 so are you comparing SS headers without cats to the stock setup on European Ms of headers and cats? Food for thought...but I do believe after reading through so many threads that SS headers are the best out there. However if youre just throwing on SS headers with no cats then yes I can see an increase of 20whp easily.

[SupersprintNA]

Originally Posted by bimmerfan08

Euro M3s also have cats in section 1 so are you comparing SS headers without cats to the stock setup on European Ms of headers and cats? Food for thought...but I do believe after reading through so many threads that SS headers are the best out there. However if youre just throwing on SS headers with no cats then yes I can see an increase of 20whp easily.

If you look through the dynos Flip posted you'll notice all of the dyno runs done by Supersprint Italy were always WITH our metallic race cats in section I.

I need to dig around some for them but I've seen many a dyno where running our cars without cats (with a catless header of course) nets little to no actual performance gain over a car running catless headers and cats in section I.

I currently have the V2 Stepped headers on my own M3. I've run both the Supersprint straight pipe section I (022 787 512) and a catted section I. My totally uncalculated and unofficial butt-dyno felt no difference between the two options after roughly 300 miles. However, the smell and the rasp were both pretty significant while running catless.