one thing that may not be so good, with the massive ports and silvertop throttles. is the low velocity area it'l leave at the port. my understanding of the best setup is, to slowly taper the inlet runner down from the bellmouth, to the port. witch will give you hi velocity at the port/ valves, increasing cylinder fill. going too big on the throttle size shouldn't matter too much. but throttle size silghtly bigger than the ports would be best option as you can mount them close to ports to increase throttle response while keeping a good taper. going bigger would mean moving them further from ports. loose a little throttle response and driveablity (depending on throttle linkage setup) but should not effect power at all, if taper and runner lenghths are same. running something big enough for the likes of a 1g or big port 4ag ports, maybe getting a little silly tho
and yeh will suck on stock ecu as others said. tune with tps vs rpm is all good. long as you have plenty of rows in fuel map at light throttle