thanks guys.. I deftly will go to 60lb even larger injectors. Yes.I should change all the valve springs, stronger pistons and so on..that is very expensive to buy them in NZ, because most of parts need to import from OZ... Does you guys know anyone can supply all of those engine parts for me with better price? Yes.. most of people say the F6 suspsion spring is very good, dont need to change them... because My F6 is BA model, so it is not comes with new BREMBO brake system. change to BREMBO brake or AP Racing brake is very dear in NZ... for 6spot at the front, 4 spot for rear, will need more than 7K AUD. For Plenum, Process West or Plazmaman, which one is better? After I done my engine job, changed Plenum, I am planning in put a bigger turbo in, which one you guys think is good? My final target is around 1000HP on RW. Many thanks to you guys again.. looking forward more advs from you guys. cheers