SR3 GDU Ratios

[derekfromnz]

Hi Guys, I've got a race meet at Manfield NZ in November and it's my first time there with my 1500 RS, the other guys who normally run there in their 1300 SR3s run a 3.409 GDU ratio - since I have a bit more power I'm thinking I should run a 3.235...(currently running standard gearing)so do you guys with 1500s normally run the next taller ratio against 1300s?.... also does anybody have a good used spare set of one of those ratios that they could sell me?
Cheers Derek