TheRealMRDyno
10+ Year Contributor
- 46
- 5
- Aug 19, 2009
-
Akron,
Ohio
Hi,
All over the web are values for 140/150 CFM / 100 HP, or 10 lbs/min / 100 HP, etc.
However, I can not quite tell if that is engine dyno HP, or chassis dyno HP, or "factory claimed" HP, or what.
So, does anyone know exactly what these numbers refer to? I am guessing chassis dyno HP, but my experience on correctly-calibrated chassis dynos makes me think these numbers are a little fudge-y. To put down 320 HP with a 2.0L engine takes quite a bit of boost and/or RPM, more than most people with 320 HP chassis dyno sheets claim to be running.
In fact, for "factory claimed" HP values, I get close to 140 CFM / 100 HP, guessing at VE values, whereas I get more like 180 CFM / 100 HP using actual chassis dyno values.
And, does anyone have logged data showing mass air flow during a dyno run, so we can take a look at this? Ideally, I would also like to know the fuel used, and injector size, fuel pressure, and logged IDC values, to get an idea of the BSFC on the 4G63T. Any additional data would be useful, too.
I can Excel-massage any data you may have in text/csv/excel/dsmlink formats, and I will post any meaningful results I can get out of it.
This is maybe engineer-boy over-thinking things, but I really like to know what I am doing before I do it.
Thanks,
Joe
Uh,
Thinking about this some more, 140/180 => 0.77, which is very close to the ~75% of factory claimed HP we measure on chassis dynos.
If the dyno values used to get the 140 CFM/100 HP value are from a Dynojet, which includes a fudge-factor to get the dyno values to match factory-claimed HP values (see press release from original owner who sold the company, after non-disclosure period ran out I think), I guess that would explain it. (I always run on Mustang dyno's with fresh and correct calibrations, since I work there.)
Joe
All over the web are values for 140/150 CFM / 100 HP, or 10 lbs/min / 100 HP, etc.
However, I can not quite tell if that is engine dyno HP, or chassis dyno HP, or "factory claimed" HP, or what.
So, does anyone know exactly what these numbers refer to? I am guessing chassis dyno HP, but my experience on correctly-calibrated chassis dynos makes me think these numbers are a little fudge-y. To put down 320 HP with a 2.0L engine takes quite a bit of boost and/or RPM, more than most people with 320 HP chassis dyno sheets claim to be running.
In fact, for "factory claimed" HP values, I get close to 140 CFM / 100 HP, guessing at VE values, whereas I get more like 180 CFM / 100 HP using actual chassis dyno values.
And, does anyone have logged data showing mass air flow during a dyno run, so we can take a look at this? Ideally, I would also like to know the fuel used, and injector size, fuel pressure, and logged IDC values, to get an idea of the BSFC on the 4G63T. Any additional data would be useful, too.
I can Excel-massage any data you may have in text/csv/excel/dsmlink formats, and I will post any meaningful results I can get out of it.
This is maybe engineer-boy over-thinking things, but I really like to know what I am doing before I do it.
Thanks,
Joe
Uh,
Thinking about this some more, 140/180 => 0.77, which is very close to the ~75% of factory claimed HP we measure on chassis dynos.
If the dyno values used to get the 140 CFM/100 HP value are from a Dynojet, which includes a fudge-factor to get the dyno values to match factory-claimed HP values (see press release from original owner who sold the company, after non-disclosure period ran out I think), I guess that would explain it. (I always run on Mustang dyno's with fresh and correct calibrations, since I work there.)
Joe
