Joined
·
12,885 Posts
FMIC temp range is consistantly 15f variation vs 50f variation for the honda intercooler.
FMIC volumetric efficiency (%) is a measure of the volume airflow through the engine vs the expected airflow if the engine filled the cylinders.
VE is way down on the Honda item as is the resulting volume airflow (note the mass airflow is also much less though so is expected to some degree).
RAW power favours the Honda intercooler but when DIN corrected, the power/airflow favours the FMIC.
Question.
How can the FMIC be capable of higher DIN corrected power when it seems to be down everywhere else ?
Discuss.....
ASSUMPTIONS
1. The Honda map will regulate the smoke level limits and hence Air Fuel Ratio will be controlled at any rpm.
2. The Honda map will regulate the torque level limits and hence control the peak corrected power the engine produces at any rpm.
3. The Honda map will attempt to keep the same torque/AFR limits no matter what the ambient pressure and temperature.
4. MAP (boost) and resulting MAF (airflow) will therefore be increased or descreased as necessary depending on weather conditions.
APPLYING DIN CORRECTION to RAW POWER...
DIN POWER = RAW POWER /((MBAR/1013.25)*((293/(TEMPC+273))^0.5))
Where
MBAR = ambient pressure in millibar
TEMPC = ambient temperature in centigrade
POWER = SEE BELOW..
OBTAINING RAW POWER FROM MASS AIR FLOW...
BHP = MAF/(AFR*(BSFC/60))
where
MAF = mass air flow in lbs/min
AFR = Air Fuel Ratio assumed to be 18:1 for a consistant comparison.
BSFC = Brake Specific Fuel Consumption ass umed to be 0.39 lbs/ bhp hour for a consitant comparison.
OBTAINING VOLUMETRIC EFFICENCY FROM RPM MAF IAT MAP
VE = (MAF*GAS*(RANKINE+IAT))/(MAP*(RPM/2)*INCHES)
where
MAF = mass air flow in lbs/min
GAS = the Gas constant R (639.6)
RANKINE = absolute freezing in Farenheit to 0f (459.67f)
IAT = Inlet Air Temp if Farenheit
MAP = Manifold Absolute Pressure in psi.
RPM =
INCHES = engine displacement in Cubic Inches (134.2 cu.in)
BLUE DOTS...
6x 3rd gear wide open throttle runs combined to allow tolerance
DATALOG ON 04 08 2012
2.5" DECAT SINGLE SILENCER  SINGLE EXIT EXHAUST
HONDA INTERCOOLER.
NO RAMAIR.
FINISHED MODIFIED AIRBOX.
AMBIENT TEMP = 27f (3 c)
AMBIENT PRESSURE = 15.23 psi (1050 mbar)
RED DOTS...
6x 3rd gear wide open throttle runs combined to allow tolerance
DATALOG ON 08 08 2012
2.5" DECAT SINGLE SILENCER  SINGLE EXIT EXHAUST
FMIC INTERCOOLER.
NO RAMAIR.
FINISHED MODIFIED AIRBOX.
AMBIENT TEMP = 34f (1 c)
AMBIENT PRESSURE = 14.79 PSI (1020 mbar)
FMIC volumetric efficiency (%) is a measure of the volume airflow through the engine vs the expected airflow if the engine filled the cylinders.
VE is way down on the Honda item as is the resulting volume airflow (note the mass airflow is also much less though so is expected to some degree).
RAW power favours the Honda intercooler but when DIN corrected, the power/airflow favours the FMIC.
Question.
How can the FMIC be capable of higher DIN corrected power when it seems to be down everywhere else ?
Discuss.....
ASSUMPTIONS
1. The Honda map will regulate the smoke level limits and hence Air Fuel Ratio will be controlled at any rpm.
2. The Honda map will regulate the torque level limits and hence control the peak corrected power the engine produces at any rpm.
3. The Honda map will attempt to keep the same torque/AFR limits no matter what the ambient pressure and temperature.
4. MAP (boost) and resulting MAF (airflow) will therefore be increased or descreased as necessary depending on weather conditions.
APPLYING DIN CORRECTION to RAW POWER...
DIN POWER = RAW POWER /((MBAR/1013.25)*((293/(TEMPC+273))^0.5))
Where
MBAR = ambient pressure in millibar
TEMPC = ambient temperature in centigrade
POWER = SEE BELOW..
OBTAINING RAW POWER FROM MASS AIR FLOW...
BHP = MAF/(AFR*(BSFC/60))
where
MAF = mass air flow in lbs/min
AFR = Air Fuel Ratio assumed to be 18:1 for a consistant comparison.
BSFC = Brake Specific Fuel Consumption ass umed to be 0.39 lbs/ bhp hour for a consitant comparison.
OBTAINING VOLUMETRIC EFFICENCY FROM RPM MAF IAT MAP
VE = (MAF*GAS*(RANKINE+IAT))/(MAP*(RPM/2)*INCHES)
where
MAF = mass air flow in lbs/min
GAS = the Gas constant R (639.6)
RANKINE = absolute freezing in Farenheit to 0f (459.67f)
IAT = Inlet Air Temp if Farenheit
MAP = Manifold Absolute Pressure in psi.
RPM =
INCHES = engine displacement in Cubic Inches (134.2 cu.in)
BLUE DOTS...
6x 3rd gear wide open throttle runs combined to allow tolerance
DATALOG ON 04 08 2012
2.5" DECAT SINGLE SILENCER  SINGLE EXIT EXHAUST
HONDA INTERCOOLER.
NO RAMAIR.
FINISHED MODIFIED AIRBOX.
AMBIENT TEMP = 27f (3 c)
AMBIENT PRESSURE = 15.23 psi (1050 mbar)
RED DOTS...
6x 3rd gear wide open throttle runs combined to allow tolerance
DATALOG ON 08 08 2012
2.5" DECAT SINGLE SILENCER  SINGLE EXIT EXHAUST
FMIC INTERCOOLER.
NO RAMAIR.
FINISHED MODIFIED AIRBOX.
AMBIENT TEMP = 34f (1 c)
AMBIENT PRESSURE = 14.79 PSI (1020 mbar)
Attachments

179.1 KB Views: 170