You will need larger injectors.
Reason: Under boost the injectors see boost pressure, so if you have stock 18 lb/hr injectors @ 43.5 psi, and you boost 6 psi, you have 16.7 lb/hr flow under boost. So you need to do a boost a pump deal or put in fatter injectors. But you will need to get 80 psi on the injectors to overcome the boost referenced reduction in fuel flow. 80. That is like 6 bar! Going up 1 bar is ok, but 3 bar? That is too much for stock parts and FPR.
So you WILL need fat injectors, at LEAST LT1 injectors to handle it. BUT you enter in new problems, you can't adjust the fuel injector constant on the 4.5L/4.9L PEFI ECM's (maybe Ed Wright has hacked it, or call Lyndon Wester). I haven't had time to mess with hacking it as I don't have a 4.9L car anymore (I do take donations!), so I can't hack away at it.
There is a lot of issues. Fuel is a dangerous one. Adding a MSII might end up being the best. My idea of a single extra injector in the airflow. Like add a injector TBI unit to the intake in place of the stock TB, and trigger it only in boosted conditions. You can add as much fuel as you could ever need. I personally would inject E85 in, but that is me...
Going boosted takes some serious thought. ANY amount of boost is a big boon to power. Even 2 psi is significant. Think of it this way, at BEST you can suck 1 BAR air into the engine, honestly a zillion factors here. But at even 2 psi boost, you are 1.1-1.2 bar, and at a lower rpm. So you are seeing your 300 cubic inches fully utilized at a much lower rpm (you don't see all inches used at anything less than WOT, if throttled, you are at less than fully used displacement...)
Can you turbo stock injectors? Yes, but I wouldn't without additional fuel delivery.
Quote:
Originally Posted by Ghost C  You're overcomplicating things yourself, seeing as how the stock injectors will support 300whp with a turbo. This has been proven by the guys with turbo 4.9's running 300whp with stock injectors.
Illumina doesn't come around here much anymore but the turbo Seville project is still being worked on as far as I know. |