Fuel Injector Size Selection

[50FoxBodyGT]

I have a 89 5.0 with GT40 heads, x-cam, and 19# injectors. How big an injector can I go while still being advantageous. Is there any other tuning or programming needed if I upgrade?

 

[jrichker]

The 19 Lb injectors are good to 300 flywheel HP. Larger injectors will require a calibrated MAF to match the sensors.

 

[50FoxBodyGT]

So, do you think my setup would benefit from upgrading to 24# injectors? How much hp would you estimate from 65mm throttle body, gt40 heads, and x-cam? I just bought the car and am in process of installing the heads. Maybe I should put some bigger injectors in while I'm at it? Hate to throw away the 19# injectors there now, they're brand new.

 

[SMOKEDYA]

I wouldnt throw them away or change them, keep'em in. You wont be at 300 with that combo. peace





john

 

[DRock9]

What happens if you are over 300HP and you still have the stock 19's? Will it damage the engine?

 

[jrichker]

What happens if you are over 300HP and you still have the stock 19's? Will it damage the engine?

You will run lean at WOT and fail to develop max power. Damage may or may not occur. It depends on if the engine starts to detonate from the lean mixture.