Data files for my 1993 roadmaster 5.7 tpi

[Jim_Rockford]

Just wondering how things look on these files. I have installed a vortec fp and shaved the ridges on the tbi , rebuilt the TBI and shimmed the regulator spring, wondering if it is too much fuel .
this file is from a cold start and long drive to work. I was having problems with the coolant temp reading low , not sure if its the actual reading or Im reading it with the wrong .bin sorry for the title it should be tbi not tpi

[dave w]

I couldn't tell what 1993 TBI .adx file was used ($OD, $E6, $31, $OE, or ???) to record the data log.

The overall BLM average was 124 (slightly rich). Ideally the BLM average will be 128, the closer to 128 the better. I only saw 531 lines of data in the .csv. I like to see about 20 minutes of data to get a good idea of what is going on.

dave w

[lionelhutz]

What have you got exactly?

I thought the 93 Roadmaster was a LT1 or L99 (4.3L V8 similar to the LT1) with a 16159278 computer????

[Jim_Rockford]

What have you got exactly?

I thought the 93 Roadmaster was a LT1 or L99 (4.3L V8 similar to the LT1) with a 16159278 computer????

No 93 was the last of the tbi 180 hp engines, 94 they went to LT1 and L99 4.3 V8 on the caprice only the data log file was A129-LO3-LO5-LB4-1991-1993-9600.ADX

[Jim_Rockford]

Longer run, this was almost my entire drive to work mostly interstate.

[Fast355]

I couldn't tell what 1993 TBI .adx file was used ($OD, $E6, $31, $OE, or ???) to record the data log.

The overall BLM average was 124 (slightly rich). Ideally the BLM average will be 128, the closer to 128 the better. I only saw 531 lines of data in the .csv. I like to see about 20 minutes of data to get a good idea of what is going on.

dave w

From 12+ years of TBI tuning experience, I tend to stay slightly richer than 128 BLM. I stay in the 122-126 range. Would rather let the ECM pull a little fuel than add it. If the BLM is greater than 128 the ECM uses the last value before it enters Power Enrichment and multiplies the fuel value by that percentage. So if it is running 134 BLM at light throttle, when you stand on it the ECM will add 7% fuel across the board. If you are targeting 12.6:1 air/fuel ratio and VE/Fueling is accurate at WOT you will suddenly see the WOT afr in the 11.7 range. If you stay a little on the rich side the engine will respond more smoothly and generally run better all around.

[Jim_Rockford]

I found a different .Bin file to use and this one has more info and I figured out what the deal withthe temp readings being so far off, its *C not *F lol the new file has both.

[dave w]

With Closed Loop = "Set" (Colum AS) the OVERALL BLM average (Colum M) = 114. The Excel formula I used to determine Overall Average =AVERAGE(M314:M1139)

Maybe Fast355 will agree with me? An overall Closed Loop BLM average of 114 is rich.

dave w

[Jim_Rockford]

thats funny cause Im running 5-6 gallons of E85 in addition to 87 e10 in a 22 gallon tank at fill ups. think that is causing the O2 to think its lean and trying to fatten it up?
On that note , I used some in my 92 Camaro B4C from time to time and this is what the intake valves looked like when I pulled the engine yesterday
https://i.imgur.com/ggiDumw.jpg
Not bad for 199k

[dave w]

Adding ethanol to gasoline effects the way an engine needs to be tuned: http://blog.innovatemotorsports.com/lambda-vs.-afr-whats-the-difference

dave w

[lionelhutz]

thats funny cause Im running 5-6 gallons of E85 in addition to 87 e10 in a 22 gallon tank at fill ups. think that is causing the O2 to think its lean and trying to fatten it up?

A narrowband O2 reads rich or lean from stoichiometric no matter the fuel. Adding extra ethanol into the fuel when using a gasoline tune should cause the BLM values to go above 128 since the engine would require more fuel to remain at stoichiometric. Same driving condition = same air but the same air requires more ethanol fuel mass then straight gasoline fuel mass.

[Jim_Rockford]

A narrowband O2 reads rich or lean from stoichiometric no matter the fuel. Adding extra ethanol into the fuel when using a gasoline tune should cause the BLM values to go above 128 since the engine would require more fuel to remain at stoichiometric. Same driving condition = same air but the same air requires more ethanol fuel mass then straight gasoline fuel mass.

So yes it should fool the O2 sensor into thinking its lean and tells the ECM it needs to add fuel hence the Rich condition.

[dave w]

Possibly the attached "How Narrow Band O2 (NBO2) Sensor Input Controls Fuel Delivery" document will be helpful?

dave w

[lionelhutz]

So yes it should fool the O2 sensor into thinking its lean and tells the ECM it needs to add fuel hence the Rich condition.

Yes, the ECM adds fuel, but the O2 sensors aren't fooled by the different fuel. They are giving the proper stoichiometric feedback as always.