[carbuff]

Low,

Thank you for chiming in! Always good to have someone 'in-the-know' to offer help and information on these forums!

Originally Posted by LowFlyin'

From 30psi up to 100psi, it was using 10.6-15.2 amps @ 13.5 volts. If I'm reading your first sentence right, you are over extending the Holley EFI relay.

That seems to be the consensus. It is interesting to me that it will hold the 58PSI consistently though until I actually open the throttle and the RPM start to rise though. You can see that on the left and right of the picture below (the pink line).

From the looks of it, the pumps is actually quite good. My numbers are showing for 675hp at the crank you'll need around 195LPH of fuel from the pump. At 60psi, the LS3 pump was putting out 220LPH by our testing equipment.

That's obviously more PSI than I was seeing, but my measurements were after the injectors, so I don't know if we are actually comparing apples to apples...

As Carl pointed out, you'll need around at least 45# injectors to keep the IDC's in the 80's with 675hp...and also a 44# injector at 58 psi will yield ~52#.

If your current injectors are essentially going static, I could see that being a source of your fuel pressure drop, as well.

This touches on a subject that I need some education on, so anyone who can help, I would appreciate it!

My car currently has 39# injectors. As best I can tell, that rating is at 3 BAR, or 43.5PSI. I'm running my system at 58PSI (at least when it keeps up), so using the formula which I've found online, that converts to about 45# equivalent.

So your statement above, that I need 45# injectors, does that mean that I have them? Or are you saying that I need 45# injectors, rated at 3 BAR?

I attempted some math to determine if I am going static or not. What I came up with is this. At 6500 RPM, each revolution takes about 9.2 mS, and 2 revolutions takes 18.4 mS. I'll paste another screenshot from the Holley Datalogger below. It's telling me that the Injector Pulse width is running consistently in the range of 16.0 - 16.3mS. If that, and the above 18.4mS at 6500RPM is correct, that would be about 87% duty cycle at 6500rpm.

Also note in the new picture below that my actual AFR is hanging at almost exactly what my Target AFR is (after recovering from Acceleration Enrichment, caused by the rate-of-change in my TPS and MAP), which was set to 12.5:1 for this run. This is also the run which shows the rail fuel pressure dropped to 44PSI.

I find several things about this interesting. First, the Injector Pulse width stays almost constant throughout the RPM range. Maybe that makes sense if I'm requesting the same AFR at all times (which I believe I am, and the Target AFR line appears to show).

So... Do I need to increase my injector size? Based on AFR, they seem to be keeping up. And do I need to keep worrying about this, if my AFR is keeping on target?

I have decided to install one of Carl's Vaporworx PWM controllers, if for no other reason than to get a clean voltage to the pump that isn't limited by my ECU. I'll be curious to see what differences that makes on my readings!

Thanx!