Autosport Labs

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

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.