ID1300x2 2008 GM truck

[castorjames]

what would be the correct way to scale those injectors on a completely stock 2008 GM truck.?stock returnless fuel system.

The double stoich half IFR still hits 63lb limit on the IFR at 304kpa.

only way i see is double stoich half IFR, run the injectors at 3BAR fuel pressure with return style fuel system and use 63.5lb/hr in all the cells of IFR table?
i would like to keep returnless if possible.
thanks

[07GTS]

return or returnless dosnt matter its if u reference the fuel reg to manifold press/vac or not, if u reference it to manifold 1:1 then u can flat line the IFR and also other changes to the offset tables to suit as well and u should be fine at the 304kpa base pressure

[castorjames]

return or returnless dosnt matter its if u reference the fuel reg to manifold press/vac or not, if u reference it to manifold 1:1 then u can flat line the IFR and also other changes to the offset tables to suit as well and u should be fine at the 304kpa base pressure

If i go return style and half ifr/double stoich:
At 4Bar pressure, scaled %50 it is at 74.032 lb/hr, still out of limits.
At 3Bar pressure, scaled %50 it is at 63.5 lb/hr, it should work ok with the correct offset tables etc..as you say but is there other way to keep returnless style and scaled correctly?

thank you

[07GTS]

u can keep return less but u will have to just reference the fuel reg to manifold if u have to flat line the IFR to suit scaling then the double/half scaling will work fine at the 3 bar, just remember to change all tables to suit scaling and referenced reg

[castorjames]

u can keep return less but u will have to just reference the fuel reg to manifold if u have to flat line the IFR to suit scaling then the double/half scaling will work fine at the 3 bar, just remember to change all tables to suit scaling and referenced reg

Sorry i cant get it 100%, if i woud like to keep returnless how do i hook a reference to the fuel reg?i think it does not has reg? fpcm pulses pump for desired pressure? i can command 3 BAR on Fuel Syst and it will follow correctly.

can you take a look when u get some time?
thank you

[07GTS]

ok thought u may have had aftermarket reg fitted, if u can mimic what the pressure does as if it were referenced then it should work, the slope that the IFR is on if u can make the fuel pressure increase and decrease at the same rate based on vacuum/boost then u can flat line the IFR and the actual pressure will do the delta, i havnt done anything with the fpcm so not sure on there adjustability

[castorjames]

Ok thank you and apreciate it , now i understand what you mean. i will have to go return style route then . thank you Sir

[2xLS1]

Is the vehicle ever going to see 304 kPa at the MAP sensor?

[castorjames]

Is the vehicle ever going to see 304 kPa at the MAP sensor?

Maybe will see 250-270kpa at the MAP, explain please

[2xLS1]

N/M

[castorjames]

N/M

If the 1/2 IFR hits the limit at 304 kPa in the table but is OK below that value, and the MAP pressure will never go that high then don't worry about it. 304 kPa is 29.588 lbs of boost. 270 kPa is 24.6568lbs of boost.

I understand that pressure delta = absolute rail pressure - map
So at stock absolute rail pressure (500kpa) minus idle map (40kpa) it will idle at 460kpa delta rigth?
i would need to run 300kpa absolute fuel pressure( 2 bar fuel pressure + baro) to idle at 260kpa delta and full vacuum at 300kpa delta..
that would keep me in range, is this ok or im overthinking it?

then i might play with Fuel system / Desired Fuel Pressure / Low flow,Normal flow, high flow to target higher pressure in WOT and boost conditions, maybe just go from 2 bar to 3 bar pressure,

also, is it ok to idle/part throttle at 2 bar fuel pressure?

thanks

[mbray01]

you dont have to scale 50%, if your settings dont fit, scale it to lower, go 40%, 33%, 25%, what ever needs to be done, just make sure you scale everything the same

[castorjames]

but with the double stoich method it has a limit of 32 afr and dont want to use the other method of scalig all the airflow etc if possible
really apreciate your time guys, thanks
will do some testing and update