Aus_speed: this is a tough one, since your idea of "performance" may be different to mine. But I'll try.
Let's start with the engine. The Mazda3 has more capacity, so with the same mods it should be capable of producing more power. It all depends on how far you are willing to go... bolt on a turbo, an intercepter chip, intercooler and exhaust and suddenly you have a 2.3L turbo capable of 200kW (250HP). Personally I'm not a fan of high powered front wheel drive vehicles, so it wouldn't seem right to me. And those mods would cost you FAR more than a few years of insurance on a 200sx!
However, I think the Mazda3 is a superbly balanced little car, much easier to drive around town, with better grip than the Nissan. Remember, they use the 200sx for drifting, b/c its so easy to slide the rear end. Trust me, the Nissan feels like its on ice sometimes, saved only by the tricky hellical differential which does a nice job of catching (accidental) tailslides.
Back to the Mazda3. The build quality is WAY above the Nissan, which in terms of power increases means that it should handle the extra horsepower/torque without developing squeaks and rattles as my Nissan did. Hop in a 2-3 yo 200sx and hit a few bumps with the windows down and you'll see what I mean. The driveline is bulletproof but the body is so-so. The Mazda feels like a bank vault in comparison. I've been in a modified 210kW Nissan S15 and the body made a lot of noise.
I'll get to the point. If you really really want to buy a Mazda3 and make the power that of a 200sx, I think it's possible but be prepared to spend some cash. Without a turbo you simply won't make the same torque - unless you're prepared to build a $10,000 normally aspirated engine (or transplant something out of a Honda). Torque is what gets a car going at the traffic lights, which is important on the street! Btw I prefer the 6 speed manual in the Nissan, it allows you to make better use of the engine's power at all speeds. I've had the Nissan up to 225km/h and sixth gear was still pulling hard up to 200. Lovely gearbox.
As for handling, I think the Mazda3 SP23 (with it's bigger brakes and sports suspension) is superb. The brakes are about 95% as good as the Nissan, with incredible feel and the added benefit of Electronic Brakeforce Distribution. It's more advanced than the Nissan and the cars weigh roughly the same, so I'd say they're about equal. The Nissan's suspension is more direct and communicates better to the driver, but as with any car the Mazda could be modified to drive just the same. The only limitation is the front wheel drive setup, which equates to a different driving style if you want to get technical about things. The mazda's spring/damper combination is awesome, the car feels like a big european sedan over speed humps but without the body roll. Perhaps the low profile tyres are a bit noisy on rough bitumen but you can't have everything! I prefer a little noise for the sake of performance. One thing I loved about the nissan was the driving position - you feel like you're in a go-cart, whereas the Mazda is a bit high.
So unless you plan to race the Mazda3 on the track, I think for 30 grand there's a whole lot of potential. If you insure with Just Cars they allow any mods so long as you tell them, and your premium shouldn't go up (at least mine didn't). So pocket the 10k difference on the Nissan and once you're out of the warranty period get a turbo kit. You should be able to blow away those Astra turbo SRi hairdresser cars no worries!
For those who don't know, the Mazda3 was engineered by the same team that developed the RX8. It's not surprising the 3 looks and handles the way it does - call me biassed but for 30 grand I reckon it's a work of art. Say no more!
:twisted:
