I have a pair of Gen 4 496 600 hp. Looking to change from solid flat tappets to hyd. roller set up. I can not go by what is in it now because I don't know what is in it. Any suggestions ??

What RPM are you trying to make power at, and what type of hull is the motor, single or twin?
What compression?

Marine Kinetics should be your first phone call.

Agreed! Call Bob! He won't do you wrong!

Marine Kinetics 585-654-8583. Ask for Yoda

It's funny, I asked for 500 horsepower with my build, and he thought that was doable...it dynoed 539, through wet manifolds, NOT dyno headers.

We made just over 800 HP working with Bob on recent 572 aspirated builds. Now we are working on (2) 500 EFI's with stock intakes , the new AFR V2 heads and Bobs cams....results coming soon.

Yep! Call Marine Kinetics, He is my cam "GURU".

I echo what the other guys said. I am actually running one of Bob's cams that I bought from BBCLiberator - one of his "spares". You will find Bob to be a wealth of information and willing to spend the time on the phone with you explaining everything and making sure you have your combo right. AND HE IS NOT ANY MORE EXPENSIVE THAN THE OTHER GUY! I learned the hard way that he is the guy you should talk to first instead of screwing around.

Hey! Where is my feedback, I guess I owe you some too.

EDIT: DONE!

Did you get it together yet?