Hyperutectic piston life

[dirtplay18]

I have a 355ci sbc in a sport mod. 9:1 with silvolite hyperutectic pistons in it, never turn it over 6800. It's due for a freshen so I'm wondering if I should think about replacing them? My other engines have forged pistons, so not really used to dealing with these. Bought the engine used with a season on it, ive ran it a couple seasons myself, with a freshen in between. Engine ran fine and still leaked down decent at the end of the season.

[Nobody]

Check the ring lands out they maybe be worn and that will make the decision for you, commonly over looked by many people.

[dereksehi]

Agree with checking the ring lands but also have the skirts measured and see if they still have the taper left in them or if they are squashed in at the tips they will commonly have .002-.004 taper from the tip of the skirt to the bottom of the oil ring land being bigger at the bottom of the skirt. If they are squashed in they should be replaced. I have had a lot of success with these pistons and never had any failures as long as they are fit right and the top ring has the right amount of gap.

[Lizardracing]

I've used the KB123 a bunch of times on circle track engines. 12:1 and 7000 rpm I put 45 shows or two years of racing in a modified and then I change them on a refresh. I haven't broken one yet. I tend to be conservative on tuning knowing I don't have much room for error because if one breaks it's going to be catastrophic.