Hmmm, mine hits just under 4000rpm at 80ish in 5th anyway. Could be that the swirl control valve is 'shut' and knackering things a bit with the vortex in the chambers, though it drives fine and fuel economy is about right.
Only weird noise I get is a whistling at 80+ into strong winds, more often with passengers. Suspect it's an air-flow issue (cold-air feed acting like a whistle or something in the blower channels) rather than a mechanical one, sounds like it's coming from somewhere in front-left quarter of the car but still can't work out where and it's a pretty constant pitch and volume not related to acceleration.
Drive it gently? Is that an option?
With mine it's foot-to-the-floor-or-your-going-backwards.
I'm not desperate to get a new car, if I could just squeeze an extra 10-20HP out of this one I'd be content as otherwise I like it fine.
It may not look that good come tomorrow, though, as I've gone mad with a touch-up kit and my track-record as a car painter is on a par with Hitler's track-record as an equal-opportunities employer.