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Does anyone have a rough figure of how much the stock 5speed box from an nb8a can handle? Or is it a case of driver style and condition of the box?

id say about 180rwkw is still just ok, any higher starts treading the fine line.

perfect!

depends how you drive it, i broke 2 5speeds at about 140rwhp, one only lasted one drift event, the other a couple.
6 speed is copeing well so far @150hp soon to be more..

Dave

Both Ian and Les's NA6's are making around 200kw.

Les's 17 year old box is still fine.
Ian's is more of a race car with an aggressive diff and he finally broke his 17 year old gear box this year.

His Kaaz diff didn't last any where near as long.

Sheck wrote:depends how you drive it, i broke 2 5speeds at about 140rwhp, one only lasted one drift event, the other a couple.
6 speed is copeing well so far @150hp soon to be more..

Dave

is it difficult to switch 6/5 speeds between cars (e.g. are the mounts similar?)

I popped 5th gear with around 160rwkw.
That was a full throttle roll on from 80kmh - bang. Pulled out to overtake a truck. No idea of the history of the box, had just bought the car.
The new box is fine but I don't try to shift too fast because it can baulk.
Jake

6 speed is an easy install, just bolts up for the most part. One bolt on the startermotor wont go in, but it has two any way, and you'll have to make up some plugs for the nutral switch and reverse switch. But thats a pice of cake!

Dave

Blue94t wrote:I popped 5th gear with around 160rwkw.
That was a full throttle roll on from 80kmh - bang. Pulled out to overtake a truck.

Accelerating hard in 5th to overtake can cause that even with probably half that power.

I've nearly destroyed 3rd gear in my 5spd....apparently the 6spd from an SE has stronger gears