Call ST Motorsports in California 1-909-388-2536. They built my motor but I dont have the break down in front of me. I did all forged internals. Manley H beam rods,JE pistons,Cobra crank. They can give you a price. Head work is overrated on these motors $3000.00 and not a huge gain.
You will not need to bore and stroke the engine to get the 550hp, but as long as it's apart, it's a good time to get it done if you want to. I would suggest going with the whole forged rotating assembly. The stock heads are capable of making 550hp, but if money is no issue, then have then CNC machined as well. Livernois motorsports does excellent work with the 4.6. They can be reached at 313-561-5500 or at New - Livernois Motorsports - Home