I have a standard 16V producing an exactly standard 139 bhp. There is a local company with a good reputation that charges around 4-5 hundred for a head port/polish/gas flow thing. I was wondering typically what power advantage I could expect for the cash? Cheers.
(OK, not totally standard - it has a stainless exhaust and k&N filter. I'd expect 142-145 right now but the cam chain is a little stretched and needs replacing - this would be done too).