Concerning my Sport wagon 455 trans plant. I am at the cross-roads weather to run headers or Manifolds that have been cleaned up? Here is what the motor is going to be. 10.5 - 10.75 to 1, 118 or comparable cam. Balanced of course with ported stage 1 iron heads. At this stage would headers be worth it? I would like to run manifolds to retain a stock apperance. Who can be recommended to work over the manifolds? I am shooting for the wagon to turn in the mid to high 12's with a 3:42 gear. Does this sound possible with this combo? Any recomendations on a Converter? I have nixed the manual conversion idea and will be sticking with a turbo 400.
this link might be a little slow loading, but it's a good one. http://www.gesslerheadporting.com/members/gesslerheadporting/ghp.nsf/sub-menu/Services03
On a combination like yours, headers will improve 1/4 mile performance by 3 tenths and 3 MPH, over 100% stock cast iron exhaust manifolds. Ported manifolds are good for about a tenth and 1 MPH over stock. 12's should not be too hard to get with decent ported heads and still retain the stock image.
