i have greddy ebc. i tuned my boost in 4th gear which will hold 18 psi perfectly. but it only hits 15-16 psi in 1st and a little bit higher in 2nd gear. i only race in autox and use 1st and 2nd gear mostly. so what gear i should be in while tuning my boost? and what's the safe boost i should set for? i have tbe, bov,ebc, safc2 and fuel pump on the way.

 

with the greddy you have 2 boosts you can use. Set it to one boost (low) for when you're autocrossing that equates to your desired boost in 1st and 2nd gear, then use the other (hi) setting for normal daily highway-type driving. I "tune" it 4th because that's where it should read the highest (i rarely boost in 5th gear)... in other words you know that anything below that is "safer". You can tune it very safely to 20psi without any fear of problems unless you're running too lean from the SAFC...