Thurs 5.12

Thurs. May 12, 2011

Jonny C's BMW E46 M3 used to have the loudest exhaust one would probably hear.  The car sounded angry and mean, and all it had was a now-discontinued RaceFlow Rear Exhaust.  It had stock headers and cats, with stock midpipes (both section 1 and 2). Even his girlfriend laughed and said, "It's ridiculous. No car needs to be that loud and obnoxious." Sorry to tell you Shay, but it's about time things got a bit LOUDER!!!

Jon purchased a set of Genuine BMW Euro Exhaust Headers from Germany. These headers have become quite popular in the world of racing, as these do not house the large catalytic convertors right up near the engine. On a stock E46 M3, there are common gains on a dyno of over 13 wheel horsepower peak and even more down lower in the rev range. And these headers can add quite a bit of decibels to your car's sound too!

The removal process was quite tricky, and took many hours to disassemble the underbody for the removal of the bulky, stock headers. All the panels and undertrays didn't take too long, but it was the removal of 18 tiny bolts that were the problem. Various DIY guides online said to remove the coolant resevoir to gain easier access to the front bolts. We didn't do that. We chose not to because we really did not want to mess with the cooling parts. So we gambled, and it took longer... But we still got it removed.

Notice the difference between the U.S. and Euro Headers.

The difference in size of the stock U.S. headers compared to the Euro ones was immense! Seeing the catalytic convertors so close up towards the engine makes one wonder really how 'efficient' and nice the S54 motor is to the environment... Anyways, the headers are out.  Since we were reusing the U.S. midpipes (both sections),  the EGT bung had to be trimmed off the U.S. header and moved downward to the U.S. midpipe, since there were no bungs in the euro headers. 

The installation process of the Euro headers was a breeze compared to taking the stock ones out.

Because the current DINAN ECU Software on the car does not support any sort of header upgrade, Jon is soon to order Turner Motorsport's Software to allow the car to fully utilize the new header upgrade. The car isn't running 100%... yet. The car sometimes stumbles under load at lower revs, but is an absolute screamer once the motor swings north of 4000 rpm. 

After the install Jon was asked if the hard work and sweat was worth it and immediately he said, "Absolutely." That's what HSM likes to hear JC.

STAY TUNED for a full video on the header upgrade!