hi there, i'm a rio 1.3 auto user from kl. in terms of increasing rio's performance, have you thought of fixing a customised exhaust header? you see, my car has a flat spot from 2,000 to 2,300 rpm. i've consulted a few workshops around kl/shah alam, only ONE gave me an logical explanation. this guy suggested that i replace the stock header with a 'tuned' header as he is specialised in doing headers, but the problem is, he is also a businessman and any proposals that do not have the economics of scale wouldn't be of much interest. say, if you're around in kl, do let me know so that we can go consult this guy again. take care brother!