Fuel Control

[Mep_q8]

Taking a look at a friends F150 file, I finally found out how to change the fueling on these vehicles. There's alot more to play with in terms of fueling, but here's the basics.

Go to Engine - Fuel Control - OL & CL - Fuel Base (Fuel Base vs. RPM vs. TPS) It shows that the fuel is calculated in Lambda's, something which I'm very new too. Did a search on the inet and came up with this table..

Scroll down to the bottom of the page... http://www.rbracing-rsr.com/rsrgauge.htm (If someone can forward me the code that will just display the calculator in here, I'm sure we could get a sticky done)

I will be hooking my LM1 up to my friends F150 in the next couple weeks and will start to play round with these tables. I do hope this tables works as accurate as the PE AFRs in the GMs

[Russ K]

AFR=Lambda*14.7

Russ Kemp

[Mep_q8]

AFR=Lambda*14.7

Russ Kemp

Cheers Russ! For some reason i didn't think the equation was that easy

[zq8bob]

Yupyup. Take the value in the table and Multiply it by that.

Russ,
I thought I read somewhere that Ford figured Lambda at 14.64.. not sure why. Is this not the case?

[Russ K]

I don't see a Stoich AFR table on the F150. Just did a 2002 Sunfre 2.2 (Stoich was 14.6). Some Gen III V8's had Stoich @ 14.63.
Scan the vehicle to find out.

I always change the Stoich to 14.68/14.7 when this table is available.

Russ Kemp

[Justin@VMP]

Yep all in lambda, not too big of a deal though since it easily converts to A/F.

Don't rely on that table to tune fuel though.

[schaid]

AFR=Lambda*14.7

Russ Kemp

Now don't you think that depends upon the fuel being used ?

As an example:

90% Gasoline 10% Alochol is 14.1 calculated AFR; but, is still 1.0 Lambda Or
15% Gasoline 85% Alochol is 9.85 calculated AFR; but, is still 1.0 Lambda.

Also, the base fuel table in the F150s is used when in Open Loop. While in closed loop, the newer F150s will do everything they can to stay at or near 1.0 Lambda for emissions control. The SCT Tuners allow a scalar setting for AFR. The HP Tuners do not. To adjust air / fuel at WOT, use the MAF Transfer table along with the Base Fuel Table.

[Russ K]

I was referring to gasoline in post #2. The screen pic is of the stoich AFR table from a 2007 Sierra 6.0L.

I understand that the fuel base table is used in open loop (when in PE). This table is for setting the commanded Lambda (AFR) when in PE. Then the Maf Airflow vs. Voltage table is adjusted to get the actual AFR to match the commanded. Basically the same way I tune the GM's.

The fuel base cold is used to command the open loop fueling vs. ECT. GM also has a similar table. In PE, the richer of the open loop table vs. ECT or the EQ Ratio vs. Rpm is used.

Russ Kemp

[schaid]

I was referring to gasoline in post #2. The screen pic is of the stoich AFR table from a 2007 Sierra 6.0L.

I understand that the fuel base table is used in open loop (when in PE). This table is for setting the commanded Lambda (AFR) when in PE. Then the Maf Airflow vs. Voltage table is adjusted to get the actual AFR to match the commanded. Basically the same way I tune the GM's.

The fuel base cold is used to command the open loop fueling vs. ECT. GM also has a similar table. In PE, the richer of the open loop table vs. ECT or the EQ Ratio vs. Rpm is used.

Russ Kemp

Thanks for the clarification Russ. Having worked with the SCT Pro Racer software for 18 months now I look forward to working with the HP Tuner software.

I have two questions for you. Have you done anything in the F150s with the Electronic Throttle settings ? Ford's factory settings limit us to a Max Throttle angle of 83. I don't have some of the settings shown in the HPT available within the SCT Pro Racer Software; but, I have read references from a SCT Tuner to adjusting these. Also, I am unfamiliar with the acronym "PE" you have used above .

[zq8bob]

PE is Power Enrichment. Basically, your Commanded AFR at WOT.

AS for the Mac Throttle, 82 is the max on the mustangs. I don't think it's truely throttle angle per-say, so much as a throttle position.

[vtanju]

Now don't you think that depends upon the fuel being used ?

As an example:

90% Gasoline 10% Alochol is 14.1 calculated AFR; but, is still 1.0 Lambda Or
15% Gasoline 85% Alochol is 9.85 calculated AFR; but, is still 1.0 Lambda.

Also, the base fuel table in the F150s is used when in Open Loop. While in closed loop, the newer F150s will do everything they can to stay at or near 1.0 Lambda for emissions control. The SCT Tuners allow a scalar setting for AFR. The HP Tuners do not. To adjust air / fuel at WOT, use the MAF Transfer table along with the Base Fuel Table.

hi,

what is the MAF Transfer table, where is it?

thanks for your help.

volkan

[Bill@HPTuners]

hi,

what is the MAF Transfer table, where is it?

thanks for your help.

volkan

Its one of the main fueling tables in any maf enabled calibration basically tells the pcm how much air is coming into the intake at all times.

Its under Engine-Airflow-General Airflow-MAF

http://www.hptuners.com/help/vcm_edi...ow_general.htm

[vtanju]

Its one of the main fueling tables in any maf enabled calibration basically tells the pcm how much air is coming into the intake at all times.

Its under Engine-Airflow-General Airflow-MAF

http://www.hptuners.com/help/vcm_edi...ow_general.htm

thank Bill

i know that table MAF airflow vs Voltage table. am i correct? i just got confused when he said MAF Transfer table.

volkan

[Bill@HPTuners]

Maf transfer, maf table, mass air table, etc...all the same, different verbage.