Seriously though, a 4-cylinder engine just isn't going to sound like a deep-toned, throaty V-8. Some people try this and they end up with that wasps nest, farting camel, rice boy sound. Also, the police can hear a car like that coming and alert them to watch the radar gun very closely. There's a lot to be said for stealth.
Lastly, a loud exhaust reduces back pressure, which is why it's loud. However reducing exhaust back pressure also reduces low RPM torque and that's what is needed to get a car moving and up to speed, as well as accelerate quickly. Reducing torque requires the driver to push deeper into the throttle, consuming more gas, which reduces fuel economy of course and increases that huge sucking sound coming from your wallet every time you have to fill up. With torque being reduced, this also makes for slower acceleration. So there's the big picture. Remember, the Toyota Corolla is an economy car and not a high performance car in any way. I hope this helps.