Just a quick question on stock injector size. The 4th gen FAQ says 93's came with 22 lb injectors, but my stock PROM says 24.1, which I assume is correct as it had never been reprogrammed when I looked at it. Granted it is a B4C, but can anyone answer this for me please?

 

I have always heard of the 93 being 24#

 

I thought GM changed from 22# to 24# in 93-94. Given the way GM likes to 'phase in' things, you may have the 24# injectors. I'd go with what the program says.

 

The phase-in thing actually makes sense, the car has a build date of sometime in May of 93, so it was one of the last 93's built. Just not something I thought of I guess.

 

I currently own a 93 and my car came with 22 lb injectors.

 

The injector constant is just a number to give the ECM a approximate idea of how large the injectors are. Nothing more.

For some reason the 93's are set to 24.1 when they supposedly have 22lb/hr injectors while the 94+ cars have their set to 24.8 w/24lb injectors.

 

As far as I am aware, the injector constant is the number used by the ECM for the fuel calculation, based on the air flow. Why would this be "an approximate idea"?

 

So if I were to change them to say 30# injectors, what number would I use in the ECM? Basically how is this number calculated?

 

'93 Camaro has #22 injectors. You do have #24 because of the police package that came with a more powerful engine.

 

Perhaps I worded that poorly. Yes, the injector constant is definately used for the fuel calculation but at the same time it does not necessarily have to match the actual size of the injector. Hence my "approximate idea".

For instance if a car is "rich" across the board (low BLM's in part throttle, rich at WOT, etc) you could either alter the values in the VE & PE tables accordingly or you could increase the injector constant slightly. Either should have the same effect (the car would lean out). Granted its probably not the "right" way to do it but its been done and the end result should be the same.

Also as you're well aware altering the fuel pressure will change how large the injector acts. Switching brands of injectors (from stock to SVO's for example) might also require a tweak of the injector constant if the two brands are rated at different pressures (which you also know).