I've always heard that extrude honing exhaust manifolds was just an expensive way to get 5 to 8 hp.
If you think about it, its not bad at all.. lets say you gain 20-25 hp with headers.. but if you have to run manifolds and you get 8-10 hp of of the extruded ones thats a good percentage of a what the header did... but yes its a bit pricey but that stuff takes time to do
