Up Up and away

Phil Lamovie phil at injec.com
Thu Oct 7 15:19:00 GMT 1999 

<HTML>


<P>Hi All,

<P>Recent postings regarding MAP sensors are in need of a little
<BR>massaging.

<P>Lets start with the definition&nbsp;&nbsp;&nbsp; manifold <B><I><U>ABSOLUTE
PRESSURE</U></I></B>
<BR>means what it says. Not relative or delta but absolute.

<P>Any ECU mapped by speed/density <B><I><U>AUTOMATICALLY</U></I></B> corrects
<BR>for engine load with altitude.

<P>Question 1

<P>How does the engine differentiate between part
<BR>throttle vacuum at sea level and full throttle at 10,000 feet ?

<P>Answer It doesn't. There is no difference.

<P>There is no need to check and record MAP value before startup.
<BR>As the pressure varies absolutely so should the fuel table value.

<P>Speed density demands only RPM and MAP (air temp correction is
<BR>not mapped but mathed. same for all other basic corrections)

<P>If the table has 16 speed values and 16 load points you will
<BR>have sufficient date to run the engine reasonably.

<P>Pilots had to correct mixtures only with badly designed fuel systems.

<P>The mech/injected engines had no such problem.

<P>Phil Lamovie
<BR>Injec Racing</HTML>

More information about the Diy_efi mailing list