I have just purchased a zex kit. Should i put bigger injectors in and if so how big 36or 42? Also should i buy a regulator if so which one is the best and also abotu how much pressure should i be running??

 

Need more info on your set-up. Is this a stock/bolt-on car or more? The stock injectors are supposed to be good to almost 400rwhp. A dyno and scan of the injector's duty cycle will tell you for sure. 90% or higher duty cycle will warrent bigger injectors. You probably won't need a different regulator. Most systems are set-up for stock fuel pressure. The Zex being a dry kit is set up to regulate fuel pressure anyway.

 

I had a wacko tune in mine and on the datalogger it showed 98% DC. Turned out it was waaaaay too rich and once I corrected it it dropped to the 70's - 80's.