I'm a newbie here but got a few questions.

My story: The original 5.9 motor in my truck dropped a valve in the block so I bought a used one and did the swap in my garage but it doesn't seem to have the same power that the old one did, but it runs ok.

My questions: I live in Northern California so I have to deal with smog, but I want to re-build the engine that dropped the valve with as much horse power and torque as possible while still being able to pass smog.

I am will to replace anything and everythingfrom the oil pan up but just need help and info on heads and anything that I can put on and still be smog legal.

Thank you for any help.