5.0 Liter TBI injector differences

I had 4.3l (43#) injectors in my project engine, and it was hitting 100% duty cycle on the injectors so I decided to go up to ones from a 5.0 liter engine.

I ended up ordering ones from 82/83 Camaro. I put them in tonight and am having trouble with getting the engine to run right. I adjusted the BPC and the VE tables, but its turning out to be a lot harder to dial in than I expected.

I just came across the fact that the 5.0 liter engine in the late 80's and early 90's trucks has a different part number for the injectors from the 82/83 Camaro.

Does anyone know what the flow rate of these Camaro injectors is? I thought they were around 55#, but perhaps I was wrong.
What other difference may there be in the injectors between the Camaro and the trucks?

Thanks.

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Originally Posted by edfiero1

I had 4.3l (43#) injectors in my project engine, and it was hitting 100% duty cycle on the injectors so I decided to go up to ones from a 5.0 liter engine.

I ended up ordering ones from 82/83 Camaro. I put them in tonight and am having trouble with getting the engine to run right. I adjusted the BPC and the VE tables, but its turning out to be a lot harder to dial in than I expected.

I just came across the fact that the 5.0 liter engine in the late 80's and early 90's trucks has a different part number for the injectors from the Camaro.

Does anyone know what the flow rate of these Camaro injectors is? I thought they were around 55#, but perhaps I was wrong.
What other difference may there be in the injectors between the Camaro and the trucks?

Thanks.

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If it was a crossfire engine, two seperate one barrel TBI units the fuel pressure for the front and rear unit are different as are the injector flow rates.

I bought the injectors as rebuilt. There was no mention of them being location specific. What was the flow rate of either of the crossfire injectors?

Bump for Monday. No 305 Crossfire guru's out there???

The regulator for CFI is in one throttle body and the other has an accumulator instead of a regulator. The front and rear injectors flow different amounts. The difference is not huge but to simplify tuning I would start with a matched pair. Unfortunately I've never seen the flow rates and I also have never opened a calibration from an original CFI ecm. I know that a 305 truck calibration installed on a 306 ci Crossfire equipped engine needed changes to the injector constant to run properly, and the changes implied that the CFI injector flow was lower.

You might be better off going with the later car or truck TBI injectors. There's plenty of data for them out there. Otherwise, just throw in the ones you have and start tuning, the flow rate shouldn't be too far off from the later injectors, but you may want to assume slightly lower.