Question about RC brand injectors

[FattyBoomBatty]

I bought some 1000cc injectors used and have them in my quest now, but after resetting the fuel map for them (up from 750cc) and changing them in the battery offset wizard, I have had to add a lot of fuel in the maps just to get them to work.

Is it safe to assume that because I have a base fuel pressure of about 36psi that these are not functioning correctly? Everywhere I look I see that 43 or 43.5 psi is the way things should be, should I just go ahead and set them for that so I have more headroom on the map?

The tables go up to 255 for fuel, and I'm touching 190 right now with only 10 psi of boost. so I kindof want a "shorter" table, if you will.

[Shane@DBPerformance]

Most injectors are rated at 43.5psi. You can run them at whatever base pressure you want though, it just changes their effective size. Too low of base and you will get poor atomization at idle/cruise. Too high and you overtax your fuel pump. If you were running the 750s at 36psi and then put the 1000s in at 36psi, then it is the same change as if they were both at 43psi as far as changing the fuel map. The 1000s might need different latency work, but that will mostly effect idle/part throttle and have very little effect on boosted fueling.

If you are using boost compensation in the AEM, then you should pretty much have the same fuel values at 10psi as you do at 30psi, so from 190 to 255 would be some decent headroom. You can change your Microbit/sec though to give you more headroom if you need it. Pretty much the Microbit/sec tells how much fuel injector on time that 1 raw unit in the fuel table is worth. So if you doubled the microbit/sec to make each fuel unit injector twice as much, then it would cut the values in your fuel table in half. It's not quite as easy as just changing that value, but it isn't hard to do.

[FattyBoomBatty]

Using RC's own converter, I figure they are effectively about 900cc injectors at this point, and if you used boost compensation when you tuned it last, which I assume you did since the table plateaus halfway up, then it's still turned on. So I'll just mess with it a little more, get it so it's driving better, and eventually bring it up for the special treatment. Thanks for the tip.