You want a good stock H.O. upgrade...
Comp Cams Magnum, part number 35-420-8, grind number 270HR. It has .533 lift, 270 duration, 215 duration as .050 lift, a 110 degree LCA and a powerband of 1800-5000. It does have a slight lope at idle, it can be used with stock torque converter if it's an automatic and stock gears. This is a recommended H.O. stock replacement cam.
About not going bigger than the E303... you have to account for duration as much as lift. This Comp cam has more lift but it has less duration and you will be fine with it. Stock 1989 pistons will accommodate this cam so no clearance problems.
Comp Cams Magnum, part number 35-420-8, grind number 270HR. It has .533 lift, 270 duration, 215 duration as .050 lift, a 110 degree LCA and a powerband of 1800-5000. It does have a slight lope at idle, it can be used with stock torque converter if it's an automatic and stock gears. This is a recommended H.O. stock replacement cam.
About not going bigger than the E303... you have to account for duration as much as lift. This Comp cam has more lift but it has less duration and you will be fine with it. Stock 1989 pistons will accommodate this cam so no clearance problems.
