Alright so this is more of an advertisement than an article, but it doe s a little expounding on the basics of TCing a 2jz-ge. Anywho I'm trying to figure out whether the author is saying that you don't need to tune this kit unless you plan on installing a fuel pump and trying to make significantly more than 300 whp? Now, I've been under the impression that it is a good idea to adjust AFRs anytime you start to alter the airflow by installing CAI's/BFI mods. what-have-you.

Pertinent quote:

The base NA 2JZGE engine with just the turbo kit will run about 7-9psi of boost on the wastegate spring and make a little over 300whp without any issues on pump gas (premium unleaded)on the factory 330cc injectors you have installed. Add a Walbro fuel pump and you can make 350whp. I must stop everyone here. Good tuning requires a wide band air fuel system (we of course sell those as well), so make sure you have a tuner who is competent. If you want to make more than 350whp, then you will need to go to 440cc injectors and or adjustable fuel pressure regulator kit and of course run the Apexi NEO or GReddy eManage (listed below) to help control everything. Next step up? If you can find yourself a good set of clean and flow tested 515cc RX-7 injectors, those will be a direct replacement for your factory 330cc injectors. With the proper fuel and tuning device (eManage or similar) and 515cc injectors and our 1.3mm headgasket kit you can make 500whp on the T61 turbo set-up running some good boost on nice higher octane performance fuel!

and Link:
http://www.suprastore.com/tosutucokit1.html

 

There is at least 2 people I know with the NA-T on stock without any aftermarket tuning. But I have heard anything more than 350hp you will need some type of AF management. Over 500 hp and stand alone with be a good idea. Just form my research. But yea 300 is simple of the stock fuel pump, ECU and injectors. Don't quote on that, just from what I heard and seen.