Another alternative...
WHAT GEAR ARE YOU RUNNING IN THE DIFFERENTIAL?? WHAT TRANS?? If your car is running around with 3.08 gears behind a C it will always feel like a slug because Clevelands like to rev, and it would also explain why the plugs are not self-cleaning. Bang for the buck, a gear change will give you the most seat of the pants change. Also, tire choice affects feel as well...a tall tire raises final gear ratio. For example, if you have 4.11 gears with a 225/60/15 tire and change to a 275/60/15, the net result would feel like you are running 3.73's on the old tires! If you post some drivetrain info I can explain further...if you dont know what gear is in the car, tell me what you are turning (rpm) at 60 and what tire you have (size). Also, what kind of trans (4 or 5 speed?). If you do this I think you can liven up your car considerably for very little $, and still have a driver! All the horsepower and torque in the world is useless unless you set the chassis up to use it!
