map recommendations?

[garyk1970]

i cannot get the ifr calcultors to work,......i guess i dont know how to operate excell?

can someone calculater my IFR?

80 lb surefire injectors
68 psi vac line off at idle

200o silverado vac referenced fpr, with oem reture....
walbro 450 intank pump with 8 ga hot wire kit...

tia

anyone? ive got 12.59 g/s??

[garyk1970]

my tune so far...
2000 silverado rcsb

2010 4.8 (15k mile) with linerfelter 58x module
ls9 cam and headgaskets
ls7 valve springs
top rings gaped @ .0028
ported heads
vvt and dod delete
trick performance stg3 turbo kit w/ front mount ic and precision 74/75 turbo
80 lb surefire injectors
4l60e auto

(4l80e trans and posi diff ready to install)

[joecar]

i cannot get the ifr calcultors to work,......i guess i dont know how to operate excell?

can someone calculater my IFR?

80 lb surefire injectors
68 psi vac line off at idle

200o silverado vac referenced fpr, with oem reture....
walbro 450 intank pump with 8 ga hot wire kit...

tia

I'll show you how...

first, some questions:
- is your FPR manifold referenced...?
If NO, then measure rail pressure directly.
If YES, then remove the reference hose from the FPR and now measure rail pressure (remember to reconnect referenece hose).
- what is measured rail pressure...?

also:
Your injectors are rated to flow 80 lb/hr at 3-bar (43.5 psi), is this correct...?

[joecar]

With that MAP sensor, you have to edit the MAP scaler/offset such that at KOEO the SAE.MAP pid shows the correct barometric pressure.

Also, using a pressure gauge and air compressor you can pressurize the MAP and verify that the SAE.MAP pid shows the same pressure (edit the MAP scaler/offset so that it does).

Or search the MAP part number and see the MAP scaler/offset values commonly used with this MAP.

[garyk1970]

Sorry for the lack of info....

Yes fpr is vaccumn referenced
Line off idle was 68 ....not a typo ( walbro 450 with hot wire kit)
Yes, injectors rated at 43

[joecar]

With that MAP sensor, you have to edit the MAP scaler/offset such that at KOEO the SAE.MAP pid shows the correct barometric pressure.

Also, using a pressure gauge and air compressor you can pressurize the MAP and verify that the SAE.MAP pid shows the same pressure (edit the MAP scaler/offset so that it does).

Or search the MAP part number and see the MAP scaler/offset values commonly used with this MAP.

EDIT: Oh, I saw this on the webpage you linked above for that MAP sensor:

Product Features

• Genuine GM Part
• 3-Bar Sensor reads up to 44 psi
• Tuning Data - Linear: 312.50 and Off-Set: -11.25

but you should still apply vacuum and/or pressure and verify that pid matches gauge.

[garyk1970]

I'll double check my fuel pressure tomorrow.....that does seem high

[johnv]

Why so high on the fuel pressure ?
Run it at 4 bar (58 psi) with vac line off.
It will still end up 78psi @ 20 lbs boost with the vac/boost reference hose reconnected.

68 psi is gonna be working the fuel pump pretty hard even just cruising around.

[garyk1970]

I'm not sure why....I haven't made any adjustments.... I don't have a adjustable fpr....I'm going to double check tomorrow.
The truck was running barely when I first checked it.


I hope you don't mind, I used your tune you posted on another thread, it helped a lot.

[garyk1970]

Maybe the OEM return line can't handle the flow of my pump?