now, here my experience with 3k engine...
well it a stock engine, at first time i got it i use to driven to it limit and reach 180km/h on highway.....the sound of it engine sure like hell......rpm?? don't know, because didnt install it yet that time.....now i have install rpm meter and what the!!!! i was going at 7000rpm and it reach 17+km/h damn!.....that only from a 3k, a 1166cc engine.....can't wait to transplant to 4k, 5k....