Just when you get used to one technology...

[BR3W CITY]

...you have to start messing with the other ones.

I was starting to feel pretty solid in my understanding of the GenIII Ecm. I messed with a handful of GenIV, and for the most part its not insanely different...but little things like GMVE instead of standard VE threw me.

Then the GenV motors came out, and it was a paradigm shift again. Sure the concepts are the same, but man some of the little stuff gets weird. Messing with the DI systems is downright scary, and their secondary high pressure pumps are specific in what they like (and they aren't cheap if you mess them up...and yes, you can kill them with a tune).
The beauty of GM is that at least you can "downgrade" your GenV to run GenIV topend, and tune it using the older system. Sounds crazy to buy a 60k+ camaro or vette and then put older stuff on it, but I'm seeing a large amount of guys do so because of the lack (and cost) of parts that can take advantage of the DI.

Now I feel old for complaining about tech. /rant

[slotard]

Do you have to swap to GenIII/GenIV heads if you want to run normal EFI?

[Cobalt964ruf]

i did not realize gen4 heads would bolt on to a gen5

[slotard]

I don't know that they will, I was just thinking that with the DI stuff on them GenV heads might not work for normal EFI.

[BR3W CITY]

My understanding is that their blocking the DI ports, ditching the pump, then using a fabbed manifold and older ECM system to run port injection. I didn't build nor tune them, only got to start at them on a dyno.

I'll text the tuner this afternoon and see if he's got an actual explanation.