Speed density or Mass air flow
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Speed density or Mass air flow ok alot of people say after 500ish horse and for boost that speed density is the best way. but we have had **** stock mass air flow uints.
has anyone tried the new Abaco style mass air flow sensor. they are digital so i figure they can pick up air better.
please give my oyu opinions. let me know what you all think. i am hoping for 1000 plus on the dyno. but like 650-850 on the street with the change of boost.
thanks
has anyone tried the new Abaco style mass air flow sensor. they are digital so i figure they can pick up air better.
please give my oyu opinions. let me know what you all think. i am hoping for 1000 plus on the dyno. but like 650-850 on the street with the change of boost.
thanks
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^^^ hard part is. that on the abaco website it says for tuning for 1000 horse. or 1300 horse. depending on the sixe you get. and it has to be good stuff right. i mean hellion does that twin turbo superchargeed kits. and uses it. so why everyone go speed density.
also how much does elevation matter? like if i get tuned at 500ft elevation. and i live at 1500ft elevation. how does that change my tune.
also how much does elevation matter? like if i get tuned at 500ft elevation. and i live at 1500ft elevation. how does that change my tune.
^^^ hard part is. that on the abaco website it says for tuning for 1000 horse. or 1300 horse. depending on the sixe you get. and it has to be good stuff right. i mean hellion does that twin turbo superchargeed kits. and uses it. so why everyone go speed density.
also how much does elevation matter? like if i get tuned at 500ft elevation. and i live at 1500ft elevation. how does that change my tune.
also how much does elevation matter? like if i get tuned at 500ft elevation. and i live at 1500ft elevation. how does that change my tune.
No personal experience with elevation changes here, so I won't comment on that.
As far as MAF vs. SD here's the basics:
The computers in these cars are hard coded to a maximum MAF airflow. Once you exceed that, the PCM can't tell what the actual airflow is. You then tweak the PE table until you get the fueling where you want it, meaning that your WOT fueling is based solely on RPM. It does not matter what MAF you put on the car your maximum measured airflow is the same (512 g/sec if I recall correctly).
With a 2 or 3 bar tune you're fueling on a calculated airflow from manifold pressure, temperature, etc... not RPM. You're only limited by the MAP sensor you are using, 2 bar or 3.
As far as MAF vs. SD here's the basics:
The computers in these cars are hard coded to a maximum MAF airflow. Once you exceed that, the PCM can't tell what the actual airflow is. You then tweak the PE table until you get the fueling where you want it, meaning that your WOT fueling is based solely on RPM. It does not matter what MAF you put on the car your maximum measured airflow is the same (512 g/sec if I recall correctly).
With a 2 or 3 bar tune you're fueling on a calculated airflow from manifold pressure, temperature, etc... not RPM. You're only limited by the MAP sensor you are using, 2 bar or 3.
Yes, the best thing about SD is you can change on the fly and it will automatically change fuel and such with the amount of boost, which really helps if you tune in july and drive in dec. because you can see a 3lb difference due to weather humidity air density etc.
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Yes, the best thing about SD is you can change on the fly and it will automatically change fuel and such with the amount of boost, which really helps if you tune in july and drive in dec. because you can see a 3lb difference due to weather humidity air density etc.
Yep so true. I dyno 760 in sanantino in Aug on 14 psi. and 813 in Ga in novmember no change in the tune no cool down. I think it was 80 degrees in sa that day and 67 degrees in GA. Speed density is godly
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+1 SD. My buddy just had anderson ford put an Abaco on his TA, i think it did pretty good he is making close to 500whp. There will be an article in the upcoming GM high performance mag. they did here at Anderson ford motorsports.
Close....sort of.....in MAF mode the PCM over 4000 rpm SOLELY uses the PE table and the MAF table....once the PCM reaches its hard limit of 512 g/sec in the MAF table of measured air, you only have the PE table left for additional fueling (read BAD). In SD mode, your pcm calculates the amount based upon the manifold air pressure and rpm and adds extra fuel with the PE table (you can also add more fuel with the BE table if you have a 2/3 bar OS from HPT, I'm sure EFILive has something similar). In these modes, your limit is only the amount of boost (either 2 or 3 bar).
No thats not the only reason, thats part of it and im sure other ppl can explain it better but if you have ever driven a force induction car you will see an actual boost difference in colder climents thus more HP, this is very true and evident during april and may when its 85 during the day and 60's at night .. you can feel a difference in the car.
I believe the cold weather (with more oxygen) actually leans it out a little equaling more power. Also i am sure the computer compensates to a point and adds more fuel so you have more fuel and air going into the motor..correct me if i am wrond on that
the computer calculates barometric pressure, so elevation changes are no big deal. Also, on 99-00 PCMs you can move timing around based on IATs, and with 01-02 OSs you can also add/subtract fuel when in PE mode with temps.
Again, that's Ford. Their systems are not VE/MAF hybrids like ours; it's their only option on the OEM hardware that I know of... AFAIK they have no underlying VE for air mass estimation, just the MAF.
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SD also gives much more control of timing in boost, with 2/3 bar EFI live COS (i'm sure HPT will have similar feature) you aren't limited to the resolution of the main spark tables and can manipulate timeing through your entire boost range.
That is true I seen 10.6 in sa and 10.8-9 in cold weather ie, GA. and more boost lol
If tuned properly, altitude will have no effect on the tune. I have personally driven from 5200 ft., where I live and tuned for SD, to 14,000+ ft. and have had no issues at all.