I am completely confused as to what to go by. ECM 7730 Mask Code $88-1227727v3

People say 100kpa is at wide open throttle "WOT", now with that being said i am using a vacuum/boost gauge. It idles around 44-55kpa with that being said obviously WOT = 0 on the gauge which to mean means 0kpa not 100kpa. If the gauge is what is confusing me then please let me know because otherwise i have been turning the car backwards.

Ill post a few pictures of what i have as far as VE and Spark-Advance, the spark advance i did modify RPM 400-800 nice and flat across and didnt touch after 70kpa which gave me a very nice smooth idle.

I'm using bosch injectors 0-280-155-700, which i called bosch-motorsports on and they are not 19-lbs/hr as everyone has said they where they are actually 20.46-lbs/hr @43.5psi. I did the math correct for my current fuel rail psi with no vacuum at 47psi 21.26-lbs/hr.

Also how and where do i enter my BPC, at first i was confusing my BPWs with BPC.

With the current tune that i have posted below which is pretty much stock on the TIMING table if you stab the gas it will hesitate for about 1-2sec and throw you into the seat all the way to 5500rpm, when you shift gears it will hesitate slightly again but not even a full second the continue pulling.

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Last edited by Armored91Camaro; 08-07-2015 at 02:33 PM.

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08-07-2015, 07:30 PM

Six_Shooter

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Re: WOT Talk

Boost gauges are generally in in/Hg (inches on mercury) and PSI. So completely different units than the formulas and what is displayed by the ECM on the ALDL data.

0 PSIG (also 0 in/Hg), is equal to 100 Kpa, which is also known as "one atmosphere". To get even more confusing, one atmosphere is actually equal to about 14.7 PSIA the A is for absolute. This is why when I'm discussion pressures as dislayed on gauges I will say PSIG, the G standing for "gauge", which is referenced to a base pressure of one atmosphere, or 14.7 PSIA. It can get rather confusing getting in depth.

Basically just keep in mind that 100 kPa = 0 PSIG and 0 in/Hg. Lower numbers in KPa are equal to units in in/Hg, on your gauge and number in kPa that are larger than 100 kPa are equal to PSIG numbers on your boost gauge.

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08-08-2015, 08:06 AM

RBob

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Re: WOT Talk

In most of the tables & individual parameters, the KPa is manifold pressure. Do a key-on, engine-off, and observe the MAP value. If at sea level it will be about 104 KPa, which is also barometric pressure.

If in Denver the pressure will be about 84 KPa.

Note that MAP is Manifold Absolute Pressure. The barometric pressure is saved by the ECM and updated when above a certain throttle position and below a certain RPM. This is referred to as pseudo barometric read.

Some parameters along with a table or two is in KPa of vacuum. One table is particular is the "Coolant Compensation SA table." Although there is a flag to use either MAP or Vacuum, GM sets it to use vacuum.

> Also how and where do i enter my BPC

Code:

; --------------------------------------
;
; Injector Constant vs. EGR airflow
;
; BPC
; 
; --------------------------------------
;-----------------------------
;	;	BPC	; airflow
;-----------------------------
L8754	FCB	182	;   0

Note that the airflow is the EGR flow rate. The zero airflow row is used when the EGR is off.

RBob.