I'm beginning to think that the deka 60lb. injectors flow a lot more than their rating at 43.5lbs fuel pressure that they list. Has anyone else used them and run into this?

 

They seem to work as advertised.

From the math, (8) 60 lb/hr injectors at 60% DC and 0.5 BSFC should support 576 hp.

In this example a 6 ms ipw resulted in 478 rwhp (dynojet, manual trans in 4th gear), so maybe 550 crank hp. Actual AFR and BSFC are unknown, but should be in the ballpark. NB O2 looks to be pretty rich (~950 mv), but certainly not drowning in fuel at this ipw/power level.

Supporting log:

https://datazap.me/u/tequilaboy/dyno...8-492&mark=436

 

Sorry I didn't clarify what I'm seeing. With VE tables decent shape, (in closed loop) set the injector constant at 60lb and wideband shows 1.5 or more richer than commanded AFR.(changed to open loop or before goes closed loop) If set the inj constant at 66lb then they pretty closely match.

 

Maybe the "VE tables decent shape" were set using injectors that didn't flow what they were rated at.

Excessive injector offset values will increase the injector flow.

Even the accuracy of he fuel pressure gauge comes into play.

No, I have not found that the Deka 60#/hr injectors flow a ton more then advertised.

RBob.

 

Thank you for the reply. I copied in offset data carefully-but I will double check it along with the fuel pressure.

 

Just curious. How are you compensating for manifold air temperature? This could be another source of error. The factory style MAT (coolant temp sensor) is way too slow to respond to rapid charge air temperature changes in boosted applications. The open cage style (IAT sensor) may be a bit better in this regard, but I haven't ever tested one.

 

I am running the "birdcage" style in the plenum (superram intake). It does respomd to changing air intake, but not all that fast-due to heatsoak? I'm not sure. I made progress when I looked at my IAT/CTS blend filter. (EBL P4). It was heavily biased to IAT-I changed it to heavily biased to CTS from tables that Rbob had posted. Sometimes I find myself just stumped-then get a breakthru from help on here.