One of my injectors has been leaking for a while causing flooding a temporary fix with a kill switch has mitigated the problem but i'm looking for a cheap upgrade. Has anybody swapped Rx8 injectors into a naturally aspirated FC? Based on little info from the Miata forums I gather they like them over the needle based injectors for their atomization and smoother idling. I also like the idea of being able to use a newer Mazda Rx8 part over reusing 25 year old injectors.

 

get yours cleaned/tested

 

Well wouldn't the cc have to be close to stock for them work without a problem?

 

+1

 

RX8 fuel injectors are designed to operate and flow 450cc at 42.5 PSI vs 38 on the RX7's stock fuel system. While they'll fit the stock fuel rails and could be controlled by the ECU, I don't think they'll flow their max cc at the system's stock fuel pressure.

 

Thanks for the info, will 4.5psi make that much of a difference? Is there a flow chart for the amount of CC per PSI for the Rx8 injectors?
Are the stock FC NA injectors 460cc at 38psi?
How critical is the NA with fuel delivery? In my mind since it's an NA running a bit lean will be better for the overall MPG. Or i got this completely wrong and I'll blow an apex seal on a hot day.

 

The pressure difference could be significant enough to result in a lean condition, and running lean means blowing your apex seals. Now, you could replace the stock FPR with an adjustable one, but if you're planning to keep the stock ECU and fuel system, it's best to simply get the istock injectors cleaned and balanced. Even if you corrected for it, it may not make much of an MPG or performance difference.

The only reason I get RX8 injectors for my NA as primaries (and Bosch EV14s 650cc as secondaries) was because not only did I get an uprated fuel pump and adjustable FPR, but also went to a standalone EFI system. I only went that route out of preference and not necessity.

If you're staying stock and want things as the factory intended, clean and balance the fuel injectors and do a full tune-up.

 

measure their dimensions.

 

You will have a lean condition on a cold day, not hot BTW

 

May not be, I'm spit balling here but a 25 year old computer system may already be running too rich as is. And aging sensors may be contributing even more. I have a wideband sensor but would need to weld a bung in either the collector or on to each individual runner of my RB header just to see how each rotor is behaving. Just what I taught, this is already turning into a xmass project.