First things I installed were a boost gauge and A/F gauge. I was hitting fuel cut in stock form. 7.5 for s4, 8.6 for s5.

A/F gauge is VERY important. You will be able to see your mixture change as you mod. You will be able to "see" when you need injectors and a fuelpump. I have even been able to see the difference in brands of gas. 92 octane from one place in not the same as 92 octane from another place. I run alot leaner on AM PM 92 octane than on Texaco or Chevron 92 octane.

I also have a coolant temp gauge and oil pressure gauge. Installed, just not hooked up yet.

YOU MUST KNOW, your boost and A/F ratio. Without that info your car is a timebomb.

 

how can u tell if your wastgate is ported with out taking it off and looking and can u post any good links to anyone that ported it . thanks alot i here its good to port it . i dont get any boost spike i have a 2.5 dp,mp and the tid mod and i see 6psi in everygear no matter how hard i beat on it and 7psi in 3rd . stock fuel system .

 

and im running really really rich .

 

from my experience there isn't an accurate a/f gauge out there. egt might be more useful. i know that in flying you tune the mixture out using egt...

also, im curious why people are saying that an FCD would be harmful to a car. maybe if you were encountering boost creep without proper fuel mods, but then again im sure hitting fuel cut isn't exactly good on the rotors anyway.