Slevy:
Yes its a conversion (callaway), I bought the turbo kit from Marksports. I drove with him last year, and the car scared the crap out of me......
1. Pistons: so I will not know the size I need until I strip her down??? so much for trying to buy things ahead......

I am planning on freshening up the entire engine, bearings, seals etc....
2. The callaway turbo system sits on the same side as the exhaust (lots of heat). I am looking at modifying my hood (924 scoop). The callaway turbo does not have the water cooling that the 951 does, so life expectancy will definitely be decreased.
3. I think detonation is and will be my major problem, but we will see how it goes.... water injection??? there has got to be a better way.
4. Clutch is a concern. I have access to a few 924 transmissions and have heard that they are able to handle more stress than the transmission in my car...... (lots of reading ahead). If I were to find an S2 transmission it would be ideal......but those are hard to come by. I will probably stay with my NA clutch until I kill it.
Either way I think it will be a fun project....
Alex