hey guys, i have swapped in 12613412 50lb injectors from glenns automotive performance (return system with factory truck intake). Could someone double check my tune and see if the changes i have made are correct. Thank you
hey guys, i have swapped in 12613412 50lb injectors from glenns automotive performance (return system with factory truck intake). Could someone double check my tune and see if the changes i have made are correct. Thank you
What is your base fuel pressure (engine running, vacuum reference hose removed)?
unsure, i havent started the engine after rebuild yet. I had researched and found some data for a return style setup and was just wanting some reassurance.Originally Posted by blindsquirrel
Well the injector flow rate depends on the fuel pressure, so can't tell you if the file is correct or not until we know what pressure they are going to run at.
58psi is normal correct? i may be misunderstanding you
Is it a fixed (stock) or adjustable (aftermarket) regulator?
The injector data in the file is correct (or, close enough, I get different numbers doing the conversion by hand but whatever) if the base rail pressure with the vacuum disconnected is 58 PSI. Whether that is the correct data to use or not depends on the fuel pressure it will see in real life actual use. If it's 43 PSI base, then the numbers need to be taken from a different pressure delta column in the Gen4 source file.
If base pressure is 43 PSI, then IFR is 43.3lb and the Offset vs Volts vs VAC table needs to be taken from the Gen4's Offset vs Press vs IGNV 300 kPa Delta column.
50 PSI base = 46.8lb = 344 Kpa Delta column
55 PSI base = 49.0lb = 380 kPa Delta column
58 PSI base = 50.4lb = 400 kPa Delta column
62 PSI base = 52.1lb = 428 kPa Delta column
it is stock regulator on factory rail
And, what's the real actual pressure as measured with a gauge? Until you get it to the point you can check that, you can't know for sure if the injector data is correct.
Ok, I'll report back after I get that. Thank you
with the key on i have 55psi and it slowly leaks down. That normal? After cranking, it idles around 60 psi. At the rail
sorry to keep replying, just trying to get you guys good info. To answer you OG question, with vacuum hose removed the engine runs at 64psi.
Flow Rate vs KPA
52.8902745872908
Offset vs Volts vs VAC
5.99679560540169
5.99679560540169
5.82894636453803
5.64583810177768
4.60822461280232
3.55535210193027
2.96025024795911
2.36514839398795
2.10574502174411
1.86160067139696
1.66323338673991
1.46486610208286
1.34279392690929
1.22072175173571
1.12916762035554
1.03761348897536
0.961318379491875
0.885023270008393
0.80872816052491
0.747692072938125
0.701915007248035
0.656137941557946
0.610360875867857
0.579842832074464
0.549324788281071
0.503547722590982
0.488288700694286
0.457770656900893
Is this a big pump with a stock dinky non-adjustable regulator?
64psi seems suspiciously high, I'd want to check that it isn't high because the fuel pump is overpowering the return orifice in the regulator (or some other restriction in the return path, would give the same effect). If this is why pressure is high, as the fuel demand from the engine increases that artificially high 64psi will fall off to the true regulated pressure, whatever that would be.
Its a quantum 255 pump, in stock obs sending unit, -6 lines to factory return rail
255lph is very nearly three times the volume of the stock pump, and the return orifice in the regulator is only 0.073". 100% of the pump's volume has to be able to flow through that tiny hole in order for the pressure to be regulated by the spring, and not by backpressure that can't get back to the tank.
Would it be wise to change the data you posted above and run it the way it is? Or should I downgrade pump size, to keep my lines the way they are? Or switch to a different style regulator and keep my pump setup?
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