[CNHSS1]

my car had an S12 mk2 box originally fitted. after breaking a couple i bought an s13 and s14 box. the s13 box, and s14box when fitted with the s13 CA bellhousing, are 50mm longer overall (in the tailhousing section actually), than teh S12 Mk2 boxes. it required the prop shortening by 50mm, but the gearbox mounting points on the box are in the same place and take the same mount as the Mk2 so its only the prop that you need to get shortened (cost me £40 inc balancing iirc).

the gearlever position is moved back 65mm though so the tunnel will need modifying too.

S14 ratios are better for my car anyway, and the latest s14 box i have has the anti surge trapdoor design too to stop the oil rushing away from the gearset asnd filling the tailshaft section.