2002 mustang gt maf scaling, cannot enter value over 64lb/hr????

[BOAT8KR]

CUSTOMER CAR: 2002 mustang gt
-AUTO
-Tuning with: MPVI2

Vortech v1 S-trim
? 3.125 blower pulley
? MAF: pmas hpx-s
1) Blow through
? 75mm throttle body
? 75mm plenum
? Stock intake
? Stock cams
? Lightly ported heads


So I have an issue with the AIRFLOW VS VOLTAGE table on the VCM EDITOR. It will not let me enter in a value over 64lb/hr. What are you guys doing to get around this?
any help would be appreciated. I will upload the tune file I am using, but PLEASE guys, this is not a complete or done tune file. So keep the bashing to a minimum.

**UPDATE**
I have decided I need to cut the displacement by 50% and adjust all affected tables accordingly to bypass this 64lb/hr stock ecu limit. Before I dive head first, does anyone know what tables I will need to adjust after cutting displacement by 50%?


Thanks guys!!

[Tancho67]

What they have done is divide the airflow transfer function; the injector low, high slope, breakpoint; engine displacement; and possibly manifold volume in half. The maf airflow fits in the table now, but the relationships between the values they changed are still the same. Their is another way to handle this also - see decipha's website.

[decipha]

http://efidynotuning.com/fuel.htm#scaling

You probably have to scale for the injectors too. I always recommend setting the injector high slope to 30.00 lbs/hr or (30/3600 == 0.0083333333333333 lbs/sec ) and scaling your tune based on your actual injector high slope / that value (30 lbs/hr). That way you know you'll never run in to a clip limit since the 64lb maf limit is just above the 30 lb/hr injector clip limit thus for any injectors you run (as a result) your injectors will go static (pegged out of injector flow) before you hit the airmass clip.

30 gives you the maximum resolution regardless of your injector size and allows the deltap multiplier to not clip.

When doing so you want to be sure to set the IDLMAF - minimum idle airmass clip (or the MINAM - minimum airmass clip in older ecu's) to 0 to prevent excessive fueling at low airmass flows due to the low airmass flow calculated.

[BOAT8KR]

http://efidynotuning.com/fuel.htm#scaling

You probably have to scale for the injectors too. I always recommend setting the injector high slope to 30.00 lbs/hr or (30/3600 == 0.0083333333333333 lbs/sec ) and scaling your tune based on your actual injector high slope / that value (30 lbs/hr). That way you know you'll never run in to a clip limit since the 64lb maf limit is just above the 30 lb/hr injector clip limit thus for any injectors you run (as a result) your injectors will go static (pegged out of injector flow) before you hit the airmass clip.

30 gives you the maximum resolution regardless of your injector size and allows the deltap multiplier to not clip.

When doing so you want to be sure to set the IDLMAF - minimum idle airmass clip (or the MINAM - minimum airmass clip in older ecu's) to 0 to prevent excessive fueling at low airmass flows due to the low airmass flow calculated.

awesome, thank you. that makes sense. I will give that a shot.

On the IDLMAF, these are all the Idle/airflow settings I have, screen shot attached. just want to make sure I see that idlmaf or MINAM you are talking about. I did notice some Cylair settings, do you guys mess with those as well? maf airlow screen shot for forum.pngscreen shot of idlemaf for forum.png

[BOAT8KR]

http://efidynotuning.com/fuel.htm#scaling

You probably have to scale for the injectors too. I always recommend setting the injector high slope to 30.00 lbs/hr or (30/3600 == 0.0083333333333333 lbs/sec ) and scaling your tune based on your actual injector high slope / that value (30 lbs/hr). That way you know you'll never run in to a clip limit since the 64lb maf limit is just above the 30 lb/hr injector clip limit thus for any injectors you run (as a result) your injectors will go static (pegged out of injector flow) before you hit the airmass clip.

30 gives you the maximum resolution regardless of your injector size and allows the deltap multiplier to not clip.

When doing so you want to be sure to set the IDLMAF - minimum idle airmass clip (or the MINAM - minimum airmass clip in older ecu's) to 0 to prevent excessive fueling at low airmass flows due to the low airmass flow calculated.

is the "FLOW RATE LOW: 0.006599903 lb/sec" is that what you are referring to? and scaling my "FLOW RATE HIGH" to 30% of what it should be, since I am scaling it 30% to clear the maf clip point?

[BOAT8KR]

I have already used the PMAS HPX scaling tool to get my maf table scaled

[decipha]

read the fuel write up a few times and it will make sense

You will need to get a ticket in to get the IDLMAF scalar added to your strategy. Without it you cannot properly tune your ecu.

[inferno1278]

Were you able to get it figured out? I'm in the same pickle now.

[Eric@HPTuners]

http://efidynotuning.com/fuel.htm#scaling

You probably have to scale for the injectors too. I always recommend setting the injector high slope to 30.00 lbs/hr or (30/3600 == 0.0083333333333333 lbs/sec ) and scaling your tune based on your actual injector high slope / that value (30 lbs/hr). That way you know you'll never run in to a clip limit since the 64lb maf limit is just above the 30 lb/hr injector clip limit thus for any injectors you run (as a result) your injectors will go static (pegged out of injector flow) before you hit the airmass clip.

30 gives you the maximum resolution regardless of your injector size and allows the deltap multiplier to not clip.

When doing so you want to be sure to set the IDLMAF - minimum idle airmass clip (or the MINAM - minimum airmass clip in older ecu's) to 0 to prevent excessive fueling at low airmass flows due to the low airmass flow calculated.

IDLMAF is the maximum airmass at idle, not the minimum. I've never had a need to change this in 20 years of tuning these cars...

The only place this is used is in the throttle position FMEM logic. It not a clip for fueling at all.

[lxlaw]

IDLMAF is the maximum airmass at idle, not the minimum. I've never had a need to change this in 20 years of tuning these cars...

I agree?. Never heard of this nor changed it? tons of scaled mustangs running great. Just multiply by .5 and keep it simple. the injector low, high slope, breakpoint; engine displacement; and manifold volume. You can adjust manifold volume for tip in tuning.