Here's a read on the subject of batch v. sequential firing. I did not write this so don't blame me. it is pertinent to the discussion I think?
https://www.enginebasics.com/E...vs%20Sequential.html
Here is a discussion of how EFI affects idle quality (from camshaft timing).
https://www.onallcylinders.com...you-may-not-like-it/
The only thing I would add that was not mentioned is that idle quality change would be more noticeable on an 8 stack system. An IR manifold plays havoc with the idle to begin with and the EFI reduces the effect of the overlap of the cam timing.
How much? I don't know.
A self learning EFI system is the current desired system. Using a laptop to tune the EFI is now close to obsolete, less desirable, old school thinking, self flagellation and probably not as accurate as the efi's cpu can do.
Let the EFI's cpu adjust everything. Essentially all you need to do is plug it in, set the idle rpm that you want, identify the firing order and engine displacement.
It is batch fired so you don't need a crank sensor. Finding the space to install a crank sensor in a Pantera is a challenge to begin with.
The "self learning" efi cpu takes some of the rough idle out of the engine depending on the cam timing. The self learning cpu balances the fuel fed to the engine at idle (and all rpm's) by balancing the a/f it reads from the oxygen sensor in the exhaust.
That a/f is pre-determined from a programed "script" it reads from. That is pre-loaded into the self learning cpu. So what happens is that if the roughness in the idle is read as an a/f balance issue, usually a "too lean idle" reading, the cpu compensates for that at idle by adding fuel to the extent it is capable of. That happens automatically.
The effect with some cam profiles is to take out some of the leaning in the intake manifold at idle caused by "overlap". I would describe that as it looks like it is calming down the engine somewhere around what taking 10° of intake/exhaust overlap would do?
If that leaning from overlap was already compensated for by something like the timing design of "George's cam" or the CompCams "Weber" profile, it won't have much effect on the idle quality.
Don't shoot me. I'm only the messenger.