Digital Tuning Ecc Iv Questions

[7991LXnSHO]

In short, is the stock computer system sequential or batch fire, and what does it use to determine RPM and rotation timing? I thought I knew, but someone knowledgeable about newer systems insisted the distributor could not be used in a sequential injection system (and was not good for a batch fire system) as it is spinning at half speed. Ignoring timing set wear, cam shaft flex and distributor gear play, to me it seems like the distributor’s pip would be easily used in computing engine speed and location. Am I just not remembering a crankshaft positioning sensor on our cars?

 

[Bullitt347]

89 and newer 5.0 with MAF were sequential EFI. There is no crank sensor on the Foxbody cars. Everything is calculated off of the PIP signal.

 

[7991LXnSHO]

Thanks! I thought I might have slipped a gear after talking with the guru.
So does anyone know if the self tuning carb replacement EFI update kits (MSD or Holley for examples) use the distributor, or if you have to add a CPS? How about with Megasquirt system?

 

[a91what]

Thanks! I thought I might have slipped a gear after talking with the guru.
So does anyone know if the self tuning carb replacement EFI update kits (MSD or Holley for examples) use the distributor, or if you have to add a CPS? How about with Megasquirt system?

All of these systems are looking for an rpm input signature. They will use the pip signal just fine for this. The MS system comes in a variety of flavors from batch fire to sequential. If you wanted to add a crank sensor you could delete the distributor and use a cam sensor in its place from an explorer.... these together open a whole world of coil opportunities and will allow full sequential tuning of both fuel and spark... with the "better" systems (ms3 or stinger pimp) you could run down the rabbit hole and tune individual cylinder fuel and timing events....


The question is what are you looking for an ems to do?