555 Aux Inj

[Walter Petermann]

Evening group,
had a busy day today..fixed 8 Jag instrument clusters and 2 ecu's (touch 
wood on the ecu's, haven't tested them yet). Then I watched the soccer 
final. Lastly, had another look at the 555 circuit. I added an op-amp to 
turn off the 555 at low loads (it's taken me since 4pm to add one op-amp!)
 Doing a search in the archives under Mapping I found a couple of 
comments on how fuel quantity is not as sensitive to RPM as it is to MAP. 
This makes me a bit more hopeful about the 555 circuit. Maybe an O2 
circuit can take it the rest of the way. 
 Next I'm going to add another input to the trigger so it can be 
connected to cars that use two injector banks, and an acceleration 
enrichment ( a cap in the input of the MAP op-amp should do it). Last
will be the O2 circuit. 
 The modified circuit is at:

http://www.brokersys.com/~corsaro/wiring_diagrams/555AuxFi.htm

 later,
  Walter