[bluebelle]

Correct me if i'm wrong, but from what I’ve observed, the manifold vacuum signals the shift light. Try this: when the light comes on, throttle back a tad until the light goes out, then creep the throttle up slowly gaining rpm - just enough to gain rpm with little vacuum increase.

You’ll see that the light will come on at different rpms. It’s reading the load on the motor, which is derived from the perceived effort the engine, is working against which is predicated by the vacuum.

Check that out. If you're seeing the light way early in the low rpms, chances are that you're opening that throttle too soon. It’s not a drag car.

Let me know what your rig does.

blue
[addsig]