As per the article Tones has linked, the Siamese port problem is the main reason why aftermarket mini injection is a single point style like the SC kit.
The Jenvey throttles would work great on a 7/8 port head with 2 of the units (so one barrel and injector per cylinder)
What about custom manifold with direct or semi direct port injection? 2 per runner sequential, Which is what my tuner was wanting to do? Still have starving issues? (I read the link which some of it is a bit beyond my pay grade lol)
Can I also ask what the difference is between the SC and the jenvey in terms of injector placement? They look to in the same place?
The Jenvey uses a Weber manifold, which means each barrel feeds one port of the a series head. The manifold runners aren’t linked
The SC feeds both ports from the single throttle
The basic Siamese problem is:
Firing order is 1342 which is the same as 3421
Ports 1&2 are grouped on a mini and so are 3&4.
To get the injection timing right you need to fire the injectors in a very specific sequence (when using one runner per port) so that all cylinders get an even distribution of fuel. The only way to get this right is using a good known injection code, probably followed up with individual exhaust port O2 monitoring
A single throttle body like the SC is able to get decent results from a simpler injection sequence as the engine can consume the air/fuel mix from the single throttle. There will still be a slight bias between the first and second firing cylinders in each port