Can i run larger injectors on my oem ecu?
i have a 86 gxl, need to get my injectors rebuilt, was thinking of using the t2 550cc injectors instead, unless i have to tune it afterward.
Any insight would help my ventures emensly.

 

You don't need larger injectors on a stock N/A, even more, you do not need larger injectors on an stock N/A with a stock ECU.

But to answer your question, yes you can run and swap in whatever injectors your heart feels like (assuming same impedance) with the stock ECU. Will it run better, no, but it will run (assuming we are talking T2 stock injectors).

 

I don't fully agree.

The ecu knows that you got the stock injectors. Because it knows that, it knows how much it needs to inject.

If you get larger injectors, then the ecu still thinks you got the stock injectors. So because the new injectors are larger and the duty cycle has been unchanged, it will inject more then needed. It will run rich, maby to rich.

So if u run larger injectors, you need to change some things in the ecu's program to let it run ok.

 

Larger injectors require that you purchase an aftermarket fuel computer or modified stock computer in order for the engine to run correctly. The stock 1980s vintage computer in your car can't be tuned like most of the 1996-later computers.

There is no point in using larger fuel injectors unless you add a turbo or bridge port your engine. If you simply want to tune the car better, then take it to a professinal tuner who will add some type of fuel computer and TAKE AWAY fuel from some areas to make it run better.

In general, to maximize the efficiency of the fuel spray you want to use the SMALLEST fuel injectors available that will still supply adequate fuel to your engine. There are some exceptions to this, but it does apply to the stock Denso fuel injectors.

If you are looking to spend money while your fuel system is opened up, then I recommend buying a new pulsation damper, replacing the fuel filter if needed, and inspecting your fuel lines and vacuum lines to see if they should be replaced. The fuel lines will tend to show many small cracks around the curved portions, and you can see this easier if you bend the line to make the bend radius smaller. Make sure you use EFI rated hose for replacement, and yes, it is expensive for a stupid piece of rubber.