AUDIOZ A4

Should I change the injectors? (I read a few posts about ppl using TT 225's?)

Otherwise I will use a 5bar FPR.

Any other tips?

Audi2ptzero

If your car uses 240cc or 270cc injectors stock with a 5 bar fpr, just match a set of larger injectors at the correct pressure. Most people have been going with 310cc injectors at 3 barif you have 240cc or 3.6 bar if you have 270cc injectors. There is no way to make the 225TT injectors work since they are 380cc.

Imolavirus@BuehnEngineering

you could make the TT injectors adapt with some software tweaking

A400

If you have the test flow (Inj. are usually tested and rated at 43 lbs or ~ 3bar, then you can take the flow you know (rated) and see what pressure you need to run to get the desired flow. There are limits on how much pressure can increase flow, but you can get pretty close. Also, some injectors respond better to increased flow than others from my experience. The orange 520cc injectors I run respond very well to increased pressure and actually give a better spray pattern at increased (more than 43 lbs) pressure. In general larger injectors have a hard time meeting lower output and low RPM demands and the smaller have a hard time at top. Given that most cant change the pulse width via SW changes then Inj size and pressure are the only real adj. you can make. to prevent buying a lot of injectors you should do the math to see the range of output avail by playing with the math b4 buying. This was just my experience when finding the combos for my old 5 cyl turbo.
Rod

bhvrdr

MTM uses tt225s on the B6 3bar fpr. Works great.