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sinr98
May 16th, 2010, 12:46 PM
Hi guys. I put some injectors in my 04 Silverado SS with the 6.0L from a 04 Sierra 8.1L. I copied and pasted all the injector info from the stock 04 Sierra tune into my tune. I heard they flow at 29.9 lb/hr. So I was going to check my values with RedHardSupra's excel worksheet and with my fuel rail pressure at 58 lbs, and my injector rated fuel pressure at 43.5 lbs. I put in 30 for my injector rated flow rate and for the new information from his calculations.
Should I put these values in B4001 Injector Flow Rate?
My old values ranged from a 29.3903 lb/hr @ 0.0psi to 32.3665 lb/hr @ 11.6psi.
I have not reflashed my pcm to the RHS values yet.
Thanks for all the help.

5.7ute
May 16th, 2010, 02:36 PM
IMHO I would just use the factory values from the engine you got the injectors from. (as long as that engine still uses 58psi fuel pressure)
GM has spent a lot of time & money to get these values correct so you would be better off keeping them.

jfpilla
May 16th, 2010, 02:42 PM
Use the attached for future calculations. Yours has some errors.

joecar
May 16th, 2010, 07:00 PM
I looked up 2004 Silverado 6.0L in the Service Manual and it says that it has a manifold-referenced FPR... is this what you have...?

This means you use the spreadsheet to compute the IFR at MANVAC=0 (i.e. the first cell), and then use this value in all cells (i.e. flat horizontal static)...

see the first cell in the spreadsheet attached by Joe(jfpilla).

joecar
May 16th, 2010, 07:06 PM
Note: if you do measure your rail pressure, and you have the manifold referenced FPR, you have to disconnect the reference hose from the FPR during the measurement.

sinr98
May 21st, 2010, 04:59 AM
Sorry I haven't got to this reply sooner. I am not sure what or how my fuel rail pressure is measured. I know it is a returnless system though. I don't have the tools to measure my FRP so I will have to find someone who has the info or tools that I can use.

I talked to Jesse @ Wait 4 Me Performance and asked him about using the spread sheet to calculate my IFR and he told me that I should stick with the stock GM values, and it don't matter that I put in the tables. As he said I can put 1.0 in the IFR and the PCM automatically compesates the IFR. I have no idea on this one.

jfpilla, I had the wrong values in the HP Tuners spreadsheet for sure. I noticed I was in the wrong sheet in the middle of the process. As for wrong info in the EFI Live spreadsheet IDK.

Thanks again for all the help and info guys