How much does this drop in cam help? Does it pull harder on top? I'm looking for more mid to top end power for my 400EX. I kind of want to go with a race cam, but then you have to change valve springs and get shorter valve guides. Do you have to get the hard-faced rockers too? I've got too much low-end power, so i'm not worried about losing some for more mid-top end power.

 

The 450/451 Web Cam pulls from mid to top. The hardwelded rockers would definitely match the hardened camshaft. I have the set in my EX and it's well worth it.