|
Bruce I think I have an answer for your speed limit issue.
If your trying to go lean it can only go lean with a limited volume of air. Otherwise it overheats. The throttle position is the first safety net to control this but I think you mentioned even that fluctuates a little. The second net is the RPM and I think the third is a combo of one and two.
The engine can handle the extra cooling needed to perform lean at around 16:1 with limited amounts of air but as you increase the AFR or the volume of air the radiator won't be able to keep up.
In order to protect itself the ECU kicks out of LB in order to cool the engine back down. I predict if the conditions just barely meet LB(coolest possible AIT) you can rev up a little higher than you can when its well inside of established boundaries.
If you bumped radiator pumps to a faster setting built in an internal resevoir(so you could flow maybe a 2 gallons of coolant and the coolant had time to reach ambient temperatures before it gets cycled back into the engine) and enlarged your radiator as well as added an oil cooler for the engine I think you could probably squeak a good deal more revs before kicking LB out. Maybe not. . . The ECU could be hardwire programmed not to allow input conditions from the driver opposed to limiting based on output conditions from sensors.
|