Definitively. More, from stock exhaust to double pipes there is a big
improvement, and than, from stock manifolds to WZ there is even more,
specially in high rpm range, much more than 2-3 HP. You CAN FEEL the
difference quite clearly in your back.
Matt
468ci 81 CS W/Z and 2.5" double exhaust with so-so mufflers....
I would expect to see more than a couple of ponies going from a stock to
duel exhaust. The olds design is pretty restrictive feeding the drivers
side
into the passenger side manifold, than forcing the gases to make a 270
degree change in direction.
JK
The W/Zs might give you 2-4 more HP. A good set of
headers will give you
20-40 more HP.
