SDS EM-4E MSD vs EM-4F

[Boosted Baron]

I understand the difference between the two systems, but can someone please explain the advantages of running the EM-4F. Is it that our distributor based ignitions that bad, outdated for racing conditions? Or is it that there's a tuning advantage to distributorless ignition with the coil packs? I'm probably way off on these theories, just my thoughts. Any help that could set me on the right track with this is appreciated.

Jon

[Speedeuphoria]

I have an F system, but its a 2.4, so no dist. Some others also seem to run the F on 8valve cars. Not sure if its better or not. But something to think about is w/ the F, you can use it on any motor(if you change projects), just make a bracket and magnet setup for the crank and your good.

If no one replies here call SDS and see what they have to say about it

[1FastCSX289]

I dont know much about the 4E system. I dont know how tuneable the spark curve is, but I can tell you the 4F system is quite nice. You can adjust spark advance in all RPM ranges under boost and under vacuum. Its very tuneable. You can make whatever curve you want.

THe stock ignition is not bad, but their are definate advantages to the DIS system. For one, its crank triggered. So, no innacuracies due to slack in the timing belt or gear train. For two, there are two coils instead of one, which means you have a longer coil saturation time (charge time) between firing events. This leads to a hotter, more consistant spark.