Played around with it today. I made a extender based on measurements from holley. I was also wondering if they run all 4 injectors together for even fuel distribution?
Installed extender
Put 1 to 1 linkage back in
Programed it back to normal.
The extender definitely solved the roll in issue. Much smoother, but it did nothing to solve the secondaries from sticking open. I still had to knock the throttle to bring it back to 0 tps almost every time. I lubed all springs and linkage joints and it did not improve.
Afr returned to normal.
It does not bind at all with engine not running. I can monitor tps and bring back slow and it always returns to 0 or 1. With engine running it wants to stay at 6 to 8 percent. Knock it like an old choke and it returns to 0 or 1.