Is there a point at which the jump between primary and secondary injector sizes
is too large?

I know a fuel managment computer can help but......?

 

meaning at which point does the size of the secondaries create a rough transition?

usually about 1000cc.........but I am running 1000cc secondaires and the transition can be felt, but its nothing extreme at all.

Bigger primaries will mostly cause rich idle.

 

Yeah pretty much.
I can feel a good kick and I've only got 550pri and 780 sec.
I haven't tuned the SAFC yet.

That should fix it right?

 

You'll never tune out the hesitation with an S-AFC, it's not nearly sophisticated enough. With a standalone and proper tuning you can get a 550/1600 combo working seamlessly, but I get the imprssion it isn't easy. There are numerous threads on it in the 3rd Gen and Single Turbo sections.

 

Thanks for the help.

 

I dunno, I run 720/1600s and the transition is seamless on the E6K.