Shockwave179:
I’m guessing Kooks, QTP or Stainless Works?
But whatever
I would go with evosports which are like $1399…
Taken from an evosport founder himself Brad Otoupalik and (M3forum.com )
Originally Posted by MSpiredM3
I take great exception to that. Please give me your metallurgical background or engineering degree to support that.
We CHOOSE to use Mild Steel on ALL our M and AMG headers for one primary reason. LONGTERM RELIABILITY. 304 Stainless (what is used on the vast majrity of Stainless BMW headers) WILL fatigue and crack and fail given the heat that an M motor or an AMG F/I motor makes. Look at the EGT’s, do some research, you will find that Stainless is far more prone to cracking due to the lack of elasticity in the metal. If you use Stainless of sufficient grade (321 or better yet 409) it will resist the heat, and last longer, but it is just a matter of time with 304. BTW, using 321 or 409 will add at leats another 30% to the price of that Stainless header.
Mild steel has elasticity due to the carbon content and allows for some give as the heat cycles happen. This is especially important in climates with bad weather where the car will go from 8000 rpm HOT EGT’s to freezing temps when sitting overnight.
If you look at the recent history of Stainless headers on the M3 (last 4 years), you will see a significant number of issues.
Our record is pretty good. Not one failure in 4 years of making headers for the AMGs and M cars.
yeah i was reading that a lot of the time, using mild steel will actually last longer then the stainless. i found that interesting. damn salt will destroy it even easier tho.