3.9 injector size

[boxerhips]

Does anybody know ( in lbs)? I have a 1995 and was told it was 167cm cubed per min. Tim

[robisonservice]

If I might be so bold as to ask . . . why?

Putting in a larger injector will not increase fuel delivery to the motor, because the ECU will just cut back the on period to compensate for increased flow when on.

If you want greater fuel flow you have to get the ECU to increase the pulse width, and you can simultaneously increase pressure. A substantial increase in delivery - enough for most superchargers, for example - is within the scope of stock injectors.

[boxerhips]

I'm looking to change the 14cux to eec-iv.

[Hans]

I believe they are 22lb/hr injectors.

http://www.fiveomotorsport.com/Injector_SetsENGLAND.asp

-Hans

[boxerhips]

Will any Bosch injectors work? (fitting wise). The A9L Mustang EEC-IV uses 19lbs w/53mm mass air meter, so it should be close. I have 19lbs injectors and the meter.

[Hans]

I don't think so. As with many lucas products, they are a slightly different size. IIRC you would need to ream out the injector bungs to fit the more common sizes. Some folks on a few EFI forums have also mentioned a different spray pattern.

-Hans

[robisonservice]

If you want to use the more generic Bosch injectors you could fit a manifold and rail from a DII motor.

I've never tried to fit Mustang fuel injection to a Rover but I think you'll find injector flow rate is not going to be a big deal with the stock injectors. Reason being the injection is going to set a pulse width that achieves proper fuel mix, and the existing injectors do that job in 3.9-4.6 configurations.

[boxerhips]

Hans the link you posted has Bosch injectors in the 3.9. Will these will go right in or do you have to ream the manifold out?

[Hans]

I think they are replacements for the Lucas injectors made by bosch.

-Hans

[Antonios]

I just tested my injectors with a multimeter and got a reading of 4.8-4.9 on one side and 4.9-5.0 on the other. The EFI test pages say that at 5-6kOhms to suspect one injector. I haven't removed them to do the other tests. Are the injectors servicable or do they need to be replaced when they go bad?

[Hans]

I don't know HOW serviceable they are, but they can be cleaned, rebuild and flow balanced professionally. For a V8 it would run around $100 for the set to give a full teardown, ultrasonic cleaning and rebuilding.

Here is the general process, though it will probably vary from shop to shop.

http://www.cruzinperformance.com/injsteps.html

-Hans

[Jack_Straw]

The stock injectors run at 19lbs. The ones from Five-0 are set to run at 22, but that's with 3 bar (43.5lbs)at the top and your stock regulator will only allow 36lbs tops. You could crush it to gain a little more, or just set yourself up with an ajustable. 100 bucks to have them reconditioned isn't bad and you wont have to mess around with your regulator and feul map.

[Hans]

Greg: I'm gonna like having you around I think :-) Finally, somebody that can answer some questions that have been bugging me about some things I wanted to try. (Such as the THOR manifold on a 3.9 with a custom EFI computer)

-Hans

[Jack_Straw]

The manifold could work without too much difficulty with the Hotwire system, it's probably going to give you gains that could be achieved easier in other ways, but it would be neat and maybe one of a kind stateside.