Sorry Phil guess your shorthand was too short for me
As for which to go with? You just have to decide what you are gong to do with the engine. Unblown stay with the std pistons and 10:1. Road work blown, you can still use the same pistons, depending on the amount of boost. I have run 14lbs boost on cast pistons at 9.5:1 on the road to 7000 rpm, no problem. I have also blown a hole in a forged piston on the road without a blower. Turbo charging produces little boost at low RPMs so there is not a lot of problems with it. The boost can go up as the rpm goes up. Water injection will hold the top end boost ok to say at 7 lbs.
If it is going to be raced, like 10 laps of a circuit using full boost, then use forged pistons and a higher boost say 14lbs plus water and every other device that will keep the combustion temp to a reasonable level.
It is the amount of time that it is going to sustain the boost and rpm that needs the lower compression ratio and forged pistons.
Harvey.
