I am considering changing out my injectors... I've got two that are not working properly and I want a performance mod.

How do I find out what the fuel delivery rating is of the stock injectors?

I have read (on a performance/mpg website) that 41# is the optimum for a '96 big block application, but I have a '93 5.0 Speed Density EFI, EEC-IV, E40D electronic overdrive.

Anyone have any suggestions on my best options... obviously, I will be chipping it to get the correct computer response, but what about the fuel pump? Can I tweak it a little to adjust the fuel flow? If so, How?

I will also be installing a twin 61mm Throttle body and a 1" fuel plenum/intake spacer to even out air flow mixture and provide more low-end torque. Later, gt40P heads, but that's a completely different nightmare.

Anyone?

 

You might want to take this question over to the performance engine forum on this site. You'll get more people seeing it there.

With a speed density EFI system I think you can pretty well froget about a larger throttle body or larger injectors.... Smarter people than me will likely tell you that as well.....

Later,

 

Larger throttle body is do-able, but stick with stock injectors unless you want to get a computer chip. The stock injectors are 19lb/hr (orange tops), which supports around 300 horsepower. The fuel pump doesn't flow very much, but should be good for as much as the 19lb injectors are good for (horsepower wise).

 

Okay, thanks guys, but just for the sake of argument, if I decided to put say... 24# injectors in, what color are they and how would I go about tweaking the fuel pump?

My longer term plans include a cylinder rebore with a stroker re-build and cam bump-up.

I definitely will be adding a chip.

 

24lb/hr injectors are blue tops. I'd say that instead of tweaking the fuel pump, get a new one with a higher flow rating, say around 155 lph or so. You'd need one for each tank if you have dual tanks. With a stroker, larger injectors would probably be a good idea, and since you plan on getting a chip, make sure the chip maker knows that you have bigger injectors so they can program the chip to use the injectors correctly.

 

Thanks... nice to have all the pieces of the puzzle before I try puttin' it together, ya know?