Okay so a bunch of ya chipped in and explained how I can do the turbo setup on FI for a reasonable amount of work.

Now dont leave me hanging........................

I hear a bunch of you yammering about stage1, stage2 and yadda yadda yadda...........

What constitutes stage one or stage two?

Why is it that I can get away with an FMU and a power commander for a stage1 but not a stage2?

Is staging not just levels of boost?

If a stock pump with FMU can achieve 100 psi of pressure, and it started off with I not good enough for big boost numbers?

I could see how having too big of an injectory for supporting the higher levels would be bad off boost as it couldnt be leaned out enough but when is it that you need to have the next level in tuning equiptment.

Again thanks to everyone for being so kind and helping me out.

While this seems to be less intrusive than a carb'd application, its more complex as I can see.


the stages are more of a name than anything. that is, there is no boost level or power level associated, EXACTLY with the stages. the general rule is that stage one is what the stock motor can handle, and stage two needs new pistons, rods, and undercutting the tranny. typically stage 1 is 300 and less hp, and 2 is 350-450. stage 3 is rarer and you dont need to worry about that one for a while....

now, the reason you dont want to run a PC and FMU on stage 2 is that the injectors would have to be too large for normal running. think about it like this: you know carb motors, correct? now, imagine that you put a holley 4-barrel on a 600, like a huge hunkin holley. wouldn't run good at all until maybe 10,000rpm, correct? same goes for injectors. the larger they are, the harder they are to control at lower hp levels.

now, people have run fmu and PC on high hp bikes, but low end drivability is sacrificed. now, the stage 2 guys have it worked out pretty nicely. they retain all stock fuel setup so they can drive just like normal in low rpms, and have stable idle at like 1000rpms. then, when they rip on it, the secondary injectors kick on about 4 or 5k rpms, about when boost hits, and then the two sets of injectors (8 in all) are running. this is why they dont need a PC or FMU. they also have a regulator to adjust fuel pressure. the FMU adjusts fuel pressure, but much moreso. the FMU will add like 10psi of fuel pressure for 1psi of intake, whereas the regulator will add more like 1:1.

so the basic answer is the stage one fuel at WOT redline will be 100psi fuel pressure and 4 injectors, and the stage 2 will be like 60psi fuel pressure out of 8 inkectors. (not sure on stage two numbers, more of a guess but in the ballpark)


oh yeah, NO STOCK PUMP!!!! dont ever use this on a turbo bike. get an aftermarket. mine will be a walboro 255 inline.

stock injectors are good for 300hp, but NOT the pump. the pump may be good for....200hp?
not sure, but i wouldn't go any higher than that.


Staging is also a level of cost,
Cheapest being a FMU, pc & bigger pump.
Second a secondary manager with boost based mapping on extra injectors or bigger primary injectors.
maybe an intercooler
Third a complete standalone ecu with the lot.
each level would require appropiate engine upgrades for the hp wanted.
lots of overlap at each stage, you could do secondary injectors at 250hp if the fmu system didn't suit your needs.


stage 1 kit here. my fuel pressure is 42psi at idle and when im cruising around. when i whack it the boost goes to around 8-9psi and the fuel pressure jumps to around70-75psi

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