My buddy has a Stock '97 GTP and he just put an ebay $25 HAI on it and you can hear the whine much better. taadaa...
But other then that, Dan and TLSheff hit it perfect. No other words are needed. And Honestly I would not do a coolant system flush, I had a bad experience where it wasn't flushed properly and I had crud in my system afterwards that caused blockages in my radiator. If you want to do it properly, unhook your heater hoses behind your alternator, flush it with a hose. Pull your radiator out and have it ("cored" I think is the right term for it?) pretty much cleaned out like new. I had mine done for like $50 or $60 at a local radiator shop. While your radiator is out, take your thermostat housing off and lay it to the side.. Next take the hose and shove it up the lower hose and turn it on.. all the coolant and water should come out through the hole where the thermostat was. Then take the hose to the thermostat hole and do the same.. do it a couple times until you see just clean water. I'd fill with straight water, get to operating temp, pull your lower hose after cool to drain. Refill with water and repeat. after clean water comes out you should be good to put green antifreeze in.
Is this more work then it's worth, maybe.. but if you have a high mileage car, you will have gunk and crust in you cooling system that the flush will break up, but may not eliminate and it could get stuck elsewhere... That's my $.02 with the coolant swap...
