Mighty 6,
What do you mean engine surge, the rpm going up and down like moving the gas pedal, or the banging sound of turbo surge?

With the data logger,
what was the turbine back pressure?
what was the boost pressure?
what was the egt. temps?
what was the A/F ratio?
what was the engine RPM?
what was the turbo RPM?

There is not a better tool than a data recorder wish I had one!

Thanks, Harry

Turbo-6