[RICK LAKE]

Mohuska Mike Who's ECU are you using? What is the Max rpm you are pushing? 60 psi is too much pressure for a system at idle unless you are running turbos or blowers. 60 pound injectors are even high rating for a 522 motor. I run a 452 and then a 482 motor with 50 pound injectors. Idle fuel pressure with a vacuum controlled regulator for fuel is 42 psi at idle and 54 psi at WOT with 3-4 psi of vacuum. My duty cycle which is the amount of time the injector is no at 6,000 rpms is 64%. Max any injector should be on is 80-85%. You can go higher but this puts a harder use of the injector drivers in the ECU. Cooling of the ECU is important to a long life of the ECU.
Mike The issues at idle at to a degree normal unless you have a IAC motor and block to control the idle. Have you talked to Al T. about gett an IAC block for your motor. IMO again IMO TWM's are for making more torque and HP over a set of webers or olbergs if the ECU is setup and tuned to the max, This means matching parts to the system. The biggest problem I have found is that most motors are running the WRONG CAMSHAFTS. A carb camshaft doesn't work as good on a TWM, Weber, or OLBERG setup. LSA is too narrow for this setup. A 112 LSA has too much time for reversion in the intake and carb bodies. 114 -116 LSA is alot better. This is about the same numbers as blower or turbo camshaft numbers. The high the vacuum the better these throttle body and carbs work.
Mike, I am building a 498 motor with a 58mm TWM setup. I have talked to Al about running a IAC block on the motor. A custom camshaft is going into my motor. It's going to be a dual profile camshaft with a wide LSA.
Send me a P-M if you want to talk more on this. Rick L.