I think the bridge port/tertiary ports open up around 7500 rpm based on the rotation of the sleeve.
That's what my bridge ported rx8 did. All on a stick ecu
The more you drive it the better the ecu compensates for the added air flow, its a smart ecu for what it is.
The problem is if you are watching the gauges all the time you are going to see things.
Best solution is to get rid of the gauge
Get some serious miles on the car and you will find that it goes away
With my bridged rx8 the "feel" of the engine power got better the more I ran it, possibly due to the engine bedding in and compression going up, but the transition of air and fuel delivery improved.
Best thing about it was that when the tertiary ports open you could feel the extra power come in and take you up to 9500 rpm without the power really dropping off
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