I autocross my NB and for me I'm quickest if I run the course in second gear. This means I bounce off the rev limiter a lot. I set up my rev limiter using the settings from Turbo Kitty which uses progressive fuel cut. Here's my question, will this damage my engine by causing a lean conditions at high RPM where I'm at highest boost. (15 PSI).

Thanks

 

No. The fuel cut happens after the cylinder has ignited and completed its cycle. So, on the next engine cycle, the ECU won't inject any fuel at all. No fuel = no combustion event. With no combustion event, there can be no damage. You might want to introduce some ignition retard on the rev limiter to ease the bouncing on the limiter, which stresses the engine mechanically.

 

Thanks for sharing your knowledge