Calculating Injector Flow rate

[joecar]

Im confused...

Ok, there you have it:
a. injectors rated at 30 lb/hr @ 43.5 psi;
b. rail pressure 58 psi;
c. non-referenced regulator;

You enter the values shown in a. and b. into the spreadsheet,
and it computes the IFR vs MANVAC table in lb/hr and/or g/s;
you then copy/paste this into B4001 IFR table.

[WiseGuyZ06]

Ok, there you have it:
a. injectors rated at 30 lb/hr @ 43.5 psi;
b. rail pressure 58 psi;
c. non-referenced regulator;

You enter the values shown in a. and b. into the spreadsheet,
and it computes the IFR vs MANVAC table in lb/hr and/or g/s;
you then copy/paste this into B4001 IFR table.

Thanks joe joe.....u da man....

[99ss]

My racetronix measures 62+ at the rail. 99 Camaro SS

[joecar]

My racetronix measures 62+ at the rail. 99 Camaro SS

Camaro has an unreferenced regulator;

You measured 62 psi at the rail (how much did it vary...? +/-1 is ok);
SVO 30 injectors are rated for 30 lb/hr @ 43.5 psi (is 30 lb/hr correct...?);

Enter those 3 values into the spreadsheet,
and it computes the IFR vs MANVAC table in lb/hr and/or g/s;
you then copy/paste this into B4001 IFR table;

the IFR table should slope upward to the right as MANVAC increases (remember, MANVAC = BARO - MAP).

If your rail pressure varies more that +/-1 or +/-2, then you have to hook up a pressure sensor and log a map of rail pressure vs MANVAC which you then use to compute your IFR table.

[powertrippin]

BTW FWIW,

I am 95% sure the SVO's are rated @ 40psi not 43
HTH
Ed

[JezzaB]

BTW FWIW,

I am 95% sure the SVO's are rated @ 40psi not 43
HTH
Ed

Most injectors have their lb/h rating at 43.5psi as an industry standard, why are these different?
Jez

[pkincy]

the more correct statement is that most GM and aftermarket injectors are rated at 3 bar.

Ford very very seldom rates their injectors at 3 bar. Most are in the 33-39 psi range as a rating.

The prevailing thinking on OBD2 LSX boards is that they are rated at 3 bar.

The OBD1 community has known since the early 90's when they were introduced that they are rated at less. I believe 39 or 39.5 psi although it easily could be 40 psi (except I don't know of Ford ever using 40 psi as a flow rating pressure.)

All my LT1s have the SVO 30s entered at 32 lbs/hr in the injector constant. (OBD1 only has a single constant not a table)

So add 7-10% to the 30 lb/hr and you are good to go.

Perry

[Goldfinger911]

The mystery continues... Read the foot note here:
http://www.fordracingparts.com/parts...tKeyField=5772

"NOTE: These injectors are flowed at 40-psi differential pressure..."

BTW FWIW,

I am 95% sure the SVO's are rated @ 40psi not 43
HTH
Ed

[pkincy]

Finally an answer.

Thank you.

This has been a controversy on OBD2 boards for some time. As this is a Ford site, we can likely count on it.

Perry

[redhardsupra]

eh, who cares what they're rated at, get it flowtested, that will tell you the real story. not all injectors are created equal