my VAFC tells me that the EMS included with my SC kit is showing the ECU about 90mmHg at full boost. i am surprised it's not at zero. because of this, the VAFC seems to be able to richen it up about 8%, and then i get bogging.

does that 8% correspond approximately to the difference between the ECU seeing 90mmHg and atmospheric pressure? or does the ECU have slightly positive fuel tables as well? or... is the bogging totally unrelated?

any opinions from the MAP experts?

 

Anything above 0 vac will send out of band data and cause bogging.. and an eventual cel. Your first statement is correct.

 

that's what i thought. i wonder why the JR EMS isn't sending 0 MAP in boost?

 

is there a comparable out of band reading for negative values? if i have it at -20% or something to help idle some big injectors, won't that cause it to see more vacuum than possible? like -800mm or something?