SiDwAyZ240 wrote:Unless your set on changing your compression, I believe that the stock rods are the weakness in the KA. You could just get some forged rods and rock the stock pistons. I think you would have to be pumping major boost to melt a piston.
If you can tune out detonation, the stock pistons will definitely outlast the stock rods. The rods bend at or just before 500 ft lbs of torque. IMHO, unless you're going for more then 450 whp you can get away with just doing a factory rebuild. New oil/water pumps, gaskets, bearings...generally clean up the entire motor. Add boost, done. The reasons a KA fails are mostly knock or issues related to a part failure like the oil pump or you overheat/undercool etc.
BUT, if you do decide to change the rods you may as well change the pistons. Then you'll have to have the entire rotating assembly balanced.