| Looking at the 955 option of boring the cases and fitting just pistons and Barrells. Using the standard 916 injectors and ECU with possibly a slightly higher fuel pressure and mapped by a PC3 I can't see it really giving a huge increase in power to keep up with your mates as all your getting is a 4% increase in capacity and higher compression. Your not getting the bigger valves and performance cams most true 955s have.
My 916Bip mades 104.5 rwhp, my 996 Bip around 116, the 996SPS if I recall rightly is around 136bhp and my 955 Corse is rated at 155bhp although the Chip in the P8 ECU does allow it to rev to 13500 rpm not something I would recommend for a road bike
Question is how much horse power are you looking for to help keep up with your mates, as getting a 916 to produce more power and be reliable your probably still going to be short of what you need
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