I fitted an R30 gearbox to my 1600 that used to be auto. Piece of cake to fit, and really light. First gear is nice and short, and gets you moving pretty quickly. the only modifications that needed to be made are the wiring for the reverse switch (different plug I think from memory) and the gearbox x-member. Oh and cutting the hole in the trans tunnel! That's it!!
I highly recommend the R30 box. They are cheap (depending on where you go around $350 from a wreckers), light and reasonably strong. (L20's are more than fine!!) 5th gear is perfect for cruising.
I think the only thing wrong with the box (because it is so much lighter than the auto) is the car then looks higher than normal due to the weight reduction
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1972 Datsun 1600, S14 SR20DET Engineered (204rwkW @ 17psi.)
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