Originally Posted by Weedwaka
This is interesting. Did they mention what kind of loss would be experienced running the 6.1 header on a 2005 - 2008 5.7 due to the port shape ?
Did the 09 - 10 5.7's get the SRT heads, or just the same port shape ?
You dont get a loss with the bigger primaries, but it does move the max torque up 500 rpm higher than stock. So depends which way you look at it. There will be less torque at the old maximum level, but gain more at a higher level. Hope that makes some sense.