Rb30 Pistons 67S20 Part Number On Top, Genuine Nissan?

[joe blo]

hi guys i just opened a rb30 i got. it has 67S20 on the top of the pistons. i want to identify what brand they are if there genuine nissan parts. do the nissan pistons have any specific markings on them?

when i google the number it comes up as the last part of the number for rings not pistons so i dunno. the rings part numbers on google is like xxxxxxx-67S20

hope someone can help

[KiwiRS4T]

You most likely have stock pistons. if they are domed they are n/a or dished = turbo. If you want to confirm just measure the bores to see if they are still standard.

[joe blo]

i measured the top of the pistons with a metal ruler. think they closer to 86mm. what size shud the actual bore be as that prob easier to measure?

the thing that got me thinking it was oversize was that all the pistons have "05" stamped on them. was thinking that was for 20 thou oversize

[iruvyouskyrine]

Stock bore is 86mm but you will need more that a steel rule to be sure. A set of verniers is ideal. Or in inside micrometer.

[iruvyouskyrine]

Pic of my standard RB30E pistons.

[nicksamaniac]

All the 30's I've opened up have had "05" or "03" stamped on top,

both turbo and na, 1 engine had a mix of both numbers.

if you look from the bottom they will have the Nissan logo embossed near or on the wrist pin boss.