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I think you might be surprised as to how much difference there is between the two gearboxes. Don't forget the S15 has a turbo, so the torque output is pretty high.

Nevertheless, I would vote for the Z car box over the S15 box. I mean, people with S15s were famously replacing the 6 speeders with 5 speeders because the little SR20 5 speeder was stronger.

I think you might be surprised as to how much difference there is between the two gearboxes. Don't forget the S15 has a turbo, so the torque output is pretty high.

Nevertheless, I would vote for the Z car box over the S15 box. I mean, people with S15s were famously replacing the 6 speeders with 5 speeders because the little SR20 5 speeder was stronger.

Maybe, I am not really familiar with the s15 boxes. But my observations have always been that gearboxes suffer the most stress and damage when they are suddenly shocked with lots of torque in a small space of time. The sr20 engine doesn't really fit into this category, even with a turbo. Sure torque output on an turbo s15 can be high, but its usually up high and once the clutch engages and everything starts building momentum the stress on components is much more linear and manageable.

Driving like an idiot is not accounted for of-course. That's why you get lots of broken drive train components and mounts because people are dumping the clutch on wide after-market wheels with grippy tires and high output engines on cars that were never designed to handle that kind of abuse.

Edited by sonicz

Will a 350z box Bolton the R34gtt though also are they any stronger than Rb25 boxes. Could be a good mod for economy and possibly higher speeds.

And no it won't bolt on. Assuming that they are common with the big frame Nissan 5 speeders (big assumption, almost certainly wrong), you have to build up a box using appropriate front and rear halves. Otherwise you're into the territory of using adapter plates. I'm pretty sure that this is how it has to be done. Plenty of VQ into R chassis conversions using the original R chassis gearbox have been documented with adapter plates, and I don't think I've ever heard of someone Frankensteining two halves of the different gearboxes together.

Frankensteining can be done with VG gearboxes, because only the bellhousing half of the box is different.

  • 5 months later...

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