Starts but won't stay running.

What kind of exhaust it may not be enough back pressure on system causing this.

From our description it really sounds like not enough back pressure or not running rich enough. Are those the injectors that are recommended for that type of setup as we don't run into this type of stuff very often. And is a 3" exhaust recommended for that type of setup as well. That seems like an awful large exhaust system for 3.0 L engine. I'd think 2 and half or three quarter would work out as well. You might try contacting Nistune support as I think you can download the way your car is reacting and they can tell or make adjustments for you I think. To me you have thrown a lot all at once at this car and you are either suffering from not enough back pressure or leaning out on th e injector side and support can give you an idea to richen it up enough to take that problem away

The try some different injectors you really need someone who can hook this up to a computer and watch what is happening on a dyno. That will be the only way to straighten it out.

I don't have a lot of experience with this that you are doing, however I do know that when you start adding boost you need to normally replace injectors with ones that are more compatible with the boost you are using as it throws more air so you need more fuel to it. ARe the injectors stock, if they are you need to add ones that have more poundage like instead of 30# go to 34# etc. If you are running a lot of boost like 8 lbs cut it down do 5 if you can. Yes it may be a tad slower but if you drive this on the street who the hell cares. You won't have the stumble. I'd also wait until nistune gets ahold of you until they may figure something out. Also is the cam what is recommended or is it the biggest one you cold stuff in it? All these factors have something to do with the way an engine runs. I kind of think you aren't really knowledgeable about this and have stuffed a bunch of money into something like a lot of people do. I don't know cause I don't know your abilities car wise. All I can tell you is good luck. One other thing if the car runs ok now then don't start screwing with the wiring cause that is where problems start wait til you hear from Nistune, you can still drive it.

From my impression of your question and replies is that I am thinking it's running lean when you have your foot into it and not normal driving. If it does it under normal driving then no but if it only does it with your foot in it then don't drive with your foot in it. And yes I saw where you added injectors but they may not be big enough for your application. Like I said wait until Nistune gets back with you on this. I have no further comments other than good luck

You must first check to see if you have spark at the plugs, injection pulse and fuel pressure, a scan if you can do that as well to check for any unresolved fault codes will be a big help in the diagnosis, start here and report back your findings.