MAP question? what is kpa
07-30-2005, 06:42 PM
#1
MAP question? what is kpa ok im in my VE table and it has RPM vs. MAP in kpa. what is kpa?
and the scale reads from 15-105 now what is this? vacuum? im not sure what mass air pressure is. when the throttle is fully open is it going to have more on that scale of MAP or less? and idling it should have?
example: is it idle=15 and fully open reading 105? not exact but in that order or do i have it backwards?
Im adjusting the lower RPMs to get it to not buck and load up. but just doing by the RPMs is ok, i'd like to adjust it by TPS vs RPM. or MAP if i can figure out how it works.
im using HP tuner. and running in speed density.
and the scale reads from 15-105 now what is this? vacuum? im not sure what mass air pressure is. when the throttle is fully open is it going to have more on that scale of MAP or less? and idling it should have?
example: is it idle=15 and fully open reading 105? not exact but in that order or do i have it backwards?
Im adjusting the lower RPMs to get it to not buck and load up. but just doing by the RPMs is ok, i'd like to adjust it by TPS vs RPM. or MAP if i can figure out how it works.
im using HP tuner. and running in speed density.
07-30-2005, 06:52 PM
#2
kpa is kilopascal, or 1000 newtons per square meter. It is a unit of pressure, like psi. There is no such thing as mass air pressure, i don't know where you got that. Map stands for manifold absolute pressure. At idle with a stock cam it will be around 40 kpa, maybe less. With an aftermarket cam it could be over 50 kpa. At higher elevations, map will be less at idle. Usually wide open throttle (no vacuum) is around 100 kpa around sea level.
07-30-2005, 06:54 PM
#3
You can only do TPS vs RPM if you have hptuners speed density enhanced software I think. Most of us who are doing speed density tuning are using the fuel trims to add or subtract from the primary and secondary ve table, which volumetric efficiency as a function of rpm and map.
