Doesn't seem likely that the frisbee prevented bucking during a downshift but I suppose there's small possibility it was helping to mask a problem you might have with injectors or tuning/tune-up. Or...it was total coincidence. If it continues, simply reinstall and report if the problem disappears.
FWIW: Extra weight you add to a motor will create an interia that helps keep the motor running. That's why a heavier FW is easier to drive with a stick than a lightweight alum one. Considering they put that weight on the WPump vs the A/C, I'm more inclined to think that extra inertia keeps the engine RUNNING smooth when the A/C kicks in.
Any chance your A/C was running and the compressor happened to be kicking on JUST as you were downshifting?
Last edited by GREGGPENN; 07-23-2010 at 06:40 PM.