Are there any known issues with the stock motor? i.e. turbo, blow off valve, injectors etc.
Also, what brand and viscosity of engine oil are you using?
Thanks Matty

Any Turbo rated oil is fine. Just be sure to regularly replace it, otherwise you have to cleanout the exhaust oil cover, to remove the scale of carbon-oil deposits, which build up and stop the turbo from turning freely.

The turbo is well under-rated (But still lots of fun for 6 months). As for the blow-off valve ..there isn't one. Use a recirculating one from another car eg. SR20DET or Lancer GSR/EVO.

Injectors max out at about 150kW, so you'll need 440cc or 550cc ones, if your turbo & internals can make the extra power. You'll need to get an aftermarket ECU, or get the original remapped to suit. The smaller the injectors, the better the idle will be. And for city cars, this is an important consideration. Stalling the engine at the traffic lights is "very uncool".

Chris

There is a whole bunch of info on the CA18DET at boostcruising.com and nissansilvia.com. They have an article on all the common problems with the CA18, and the SR20 too.

Give them a try, and let us know if all their links are dead (I haven't checked them for a while)