thesameguy
Famous Member
Mercedes and VW stuck with K(E)-Jetronic for *years* - I think largely because they were comfortable with it, but partly because it wasn't drastically inferior to contemporary batch-fired fully-electronic injection. '80s K-Jet vs. '80s L(H)-Jet? Kinda meh once you get over the packaging. There is only one component you *need* to run K-Jet, and that's the metering plate that affixes to the top of the airbox and regulates flow at the injectors. All the other stuff - thermoswitches and air valves, etc. are for emissions or idle compensation or cold/hot enrichment. The thermo-time switch and the warm-up regulator solve enrichment, so with them and the metering plate you'd have a car that runs at least as well as a carb'd car. Since it was in pretty widespread use for over twenty years Bosch CIS ("constant injection system") has a lot of hacks for tuning and you can power double digit or triple digit outputs no problem. It's not a smart system - I mean, it was designed in the '60s! I made pretty good power with my turbocharged 8v Saab using CIS and parts assembled from Volvos and Porsches - but that was back in the day. IMHO, the big issue *today* with CIS is that the newest CIS parts are over twenty years old now and some parts are VERY difficult to find or, best case, you end up buying them from Mercedes or Porsche at very high prices. Keeping a CIS system in good nick in 2014 can be *very* expensive. I long ago converted that Saab to LH (pulsed/batch fired) injection because keeping it running costs nothing except used Mustang fuel injectors every so often.
IMHO, the roadblock to fuel injecting the small six is the bloody intake manifold, and that's a roadblock whether you use constant or pulsed injection. You gotta get those injector bungs installed. After that, whether it's playing with metering plates or plugging values in a table you're going to invest some time. Nice thing about computer-controlled injection is that any decent tuner with a dyno can get you some pretty good tables pretty quickly, whereas metering plates are a bit more of a PITA (though not unlike playing with carb jets!).
IMHO, the roadblock to fuel injecting the small six is the bloody intake manifold, and that's a roadblock whether you use constant or pulsed injection. You gotta get those injector bungs installed. After that, whether it's playing with metering plates or plugging values in a table you're going to invest some time. Nice thing about computer-controlled injection is that any decent tuner with a dyno can get you some pretty good tables pretty quickly, whereas metering plates are a bit more of a PITA (though not unlike playing with carb jets!).