oldbee
Well-Known Member
Yup, but those are some of the better factory manifolds ever installed.You’ll always get a more “tinny” sound from headers. Lose heat faster when shutdown, and then difference in tubing dia. makes a difference on the street also.https://www.hemmings.com/magazine/mus/2017/07/How-Hot-The-Hemi-/3750986.html
This is the 426 Hemi I purchased from Don at RAD machine and transplanted in my 67 Coronet RT tribute convertible. You can see dyno results with factory headers vs racing headers. Not a huge difference.