99 5.9 factory camshaft

in 249 ex269
.410 .417
41 degrees overlap

99 318 factory cam shaft

in 250 ex264
.432 .432
31 degrees overlap

Mopar magazine did a ex test on the 300 hp crate motor and it made 300 hp with 318 ex manifolds and 325 or so with TTI headers, I would think a better cam and better intake could make 25 more hp