'165 computer running a modified APYU base code on a Superram. Ran great on longtube TPI. With Superam I raised the shift points in the trans to 6100-ish. Hard to get that precise, but 6000RPM was my target. The 1-2 shift is fine - happens at 6000-6100 in TunerproRT. The 2-3 shift doesn't happen - AT ALL. But what it does is get up to 6300-ish and then flutter up and down 1-200 rpm.

My Rev-Limit stop fuel is set to 6514 RPM with a return at 6387 RPM. It feels like I am stuck in this zone and the trans won't shift.

I'd expect the engine to rev up more than it is, if the problem was simply a Trans not shifting issue. The fact that it kind sticks around 62,6300 suggests it's being limited.

Now ... any idea what data point to look at to verify I am at the fuel cutoff limit? I don't see any values. The Inj Pulse rate doesn't change.

I'm going to tweak my govenor and lower the shift point 200rpm or so ... see if that solves it. A bit hesitant to raise the fuel cutoff number.

Mark.

 

As a test just raise the limit way up.

It could be that the valve springs are floating (valves actually).

RBob.

 

Thought about that ... but was looking for a data point.

I'm doubtful on valve float. Edelbrock RPM's from back in the day ... overkill for a TPI engine. But you never know.

I was trying to find the code the the $6E hac to see what it did with the Rev limit ... so far no luck finding the part of the code.

 

But you aren't running TPI... And valve springs do get tired.

RBob.

 

You should see the injector pw go to zero during fuel cut. If necessary for testing increase the hysteresis between the off rpm and on rpm points to extend the duration of the fuel cut event so that you can capture it clearly in a datalog to see what is really happening.

I've used 2,000+ rpm off/on hysteresis to serve as a no-lift/no-clutch/power-shift feature. With such a significant rpm drop, you can't miss it (even without data).