The TF240 heads are good for 600 hp out of the box but everything else needs to be properly matched. Your compression ratio will most likely go up so you need to figure it out before you order parts. Are you willing to run race gas? You might need it with the TF heads. Are you running open headers? Figure out what your target trap speed is and work backwards to figure out the trap RPM and then see where that puts you for the camshaft.
Me thinks you need to be in the 675 hp range. Andy - you don't think the TF270 would be a better choice?
I'm hoping to go low 10's in my 3800 - 3900 lb GTX (if I ever get it done). It made 713 hp 707 torque with TF 270 heads. Street/strip car.
