Hi guys, I have a JDM 95 WRX with what I guess is an STi motor (has 5th injector). Now my TD05 seems to be nearing the end of its life, and there's a much respected WRX guru around here with about 10 years' experience in early rexes who has offered to put in a VF34 for me.
Now, he says that it is safe to put in the VF34 without getting a tune, and the only supporting mod I need is the 255lph Walbro fuel pump (which I installed today). What are your thoughts on this? I am inclined to believe him because of his experience but then there's this attitude in the WRX community of if you do any mods without a tune your engine will die.
Also I am not really planning to up the boost, I have a Z4 ECU running at the stock 12.78psi. I may contemplate raising it to about 15psi if safe. As I am planning to run stock boost though, my main concern is the engine leaning out early in the power band as the VF34 spools faster. Also I should note my knock sensor is pretty much redundant as we had to move it to another location as it kept picking up false knocks from general engine noise and putting the car into limp mode.
So what are your thoughts on swapping the TD05 with a VF34 and no tune on a V2 rex?