I've jsut finished with a forum article on USMB Subaru forum that might interest some members here.

http://www.ultimatesubaru.org/forum/topic/153928-high-output-coils/ 

As you all know my ea81 has been totally rebuilt with a SPFI manifold and 38/38 weber. The 38 will be swapped for a 32/36 soon as the 38 is really too big but wanted to experiement.

What I did was, when the engine was brand newly recoed, was instal a stock Subaru coil and new module. But I had a msd master blaster 2 coil since the days I supercharged the engine. Before I installed this coil I started the above thread as I didnt want extra trouble....just maximum spark and economy/performance.

Some of you might find it interesting reading.

One recommendation was to use the 02 sensor bung in the exhaust (I had one installed for my SPFI set up) and for me to fit a air/fuel gauge. Have any of you fitted one, cost and benefits eg worthwhile? can I use that gauge to tune my carby?