Hi guys,
First post on here and it may be a really easy question to answer...
I'm running a Mini 1000 with MAP not TPS. My question is on the ignition maps that i've looked at http://www.autosportlabs.org/viewtopic.php?t=1946 it lists load against RPM does it make a difference what reference i'm using for my load?
Sorry if this is a stupid question just can't get my head around it!
THANKS GUYS
TPS to MAP
Moderators: JeffC, rdoherty, stieg, brentp
It does make a difference is the short answer
With TPS it's usually linear as the TPS is measuring how much the throttle butterfly is open ie 10, 20, 30 % whereas a MAP sensor is measuring manifold vacuum (as a absolute pressure hence M.anifold A.bsolute P.ressure) At small throttle openings the manifold vacuum is very high but decreases in a non linear way as the throttle butterfly opens as it's a change in pressure.
So 50% of TPS doesn't = 50% manifold Vacuum.
You cannot therefore simply use the spark table from a TPS cal. if you're running a MAP you have to have the same type of cal. or it'll go horibly wrong!
BV.
With TPS it's usually linear as the TPS is measuring how much the throttle butterfly is open ie 10, 20, 30 % whereas a MAP sensor is measuring manifold vacuum (as a absolute pressure hence M.anifold A.bsolute P.ressure) At small throttle openings the manifold vacuum is very high but decreases in a non linear way as the throttle butterfly opens as it's a change in pressure.
So 50% of TPS doesn't = 50% manifold Vacuum.
You cannot therefore simply use the spark table from a TPS cal. if you're running a MAP you have to have the same type of cal. or it'll go horibly wrong!
BV.