I took out the rear baffle, already full of small holes, with a hole saw. The middle one, also full of holes from the factory, is untouched. I feared taking out the front one would turn out to be too loud so I drilled four 9 mm holes in it. Four to start with...
The sound improved (throatier) with removing the rear baffle. Pinking was less. Pinking almost gone after drilling the front baffle and pipes no longer glow red.
Conclusion: I would suggest drilling holes in the front baffle to start with. Four of them around the edge is not hard to do, and leaves the option to hole saw it as well. If you use a hole saw bit, without the hole saw, you get a perfect distance from the muffler wall. "North", "south", east" and "west". Using an impact drill makes the bit bite much earlier. Add four more holes in between, as preferred.
I would not start with the rear baffle if I were to do it again.
Still, it sounds better and the car runs MUCH better.
STOP PRESS!!!!!!!! George from KH called me today,i know someone actually called back! there new improved stage 2 pipes are coming in (well thats what there supplier says) Will now hold off the drilling process for a few more weeks
