On a related topic, the exhaust manifold is pretty tight on the HC and I was thinking of installing a kooks long tube headder, has anyone measured the difference in Torque/HP after changing out the exhaust mainfold?
Below is from a test they ran on a 6.0 "BluePrint" small block with some upgrades.
"It’s pretty much a given that the long-tube headers will net the highest peak-power rating, but the purpose of this test is to find out just how much of a difference there is between the different style headers.
Below you’ll see just how much power the engine made with each setup:
- Log-style, cast-iron manifolds : 474.2 hp @ 5,700 rpm / 453.2 lb-ft of torque @ 5,400 rpm
- Mid-length headers : 488.2 hp @ 5,700 rpm / 464.3 lb-ft of torque @ 5,400 rpm
- Long-tube headers : 494.5 hp @ 5,700 rpm / 474.3 lb-ft of torque @ 5,400 rpm"
gmauthority.co , Cast-Iron Manifolds Vs Long Tube Headers | GM Authority
It would make sense if your changing out the exhaust then go ahead and tackle the manifold at the same time, if you plan on doing that also.
If anyone is looking at cutting weight, what does a carbon fiber exhaust save over Stock OEM? My buddy is trying to figure out just how light he could possibly get his Challenger so I'm coming up with "creative" ideas.