Na-T 5 speed manual

Evening all I’m currently having a dilemma regarding a 5 speed na-t supra I have been offered I have been reading through the forums and have come across some good info however not necessarily found my answer..

So overall from what I have gathered mainly restricting this car is the gearbox exceeding around 380bhp from different forums and online I have been reading horror stories that the w58 just wont take anymore and potentially is going to give up .. I have looked at the price of 6 speed boxes and well I’m shocked at the price let alone the other kit required to make that conversion as I’m aware it’s not just straight forward ... I’m willing to spend the money if that’s the best route to go down ...

Now personally for me I would be content for around a year with the power the car is running however deep down I know I will want more and that box will restrict me or go wrong ..

Going through some old threads I have seen someone had made a Nissan gearbox fit and also seen mentioned about a bmw gearbox .. ???

So I suppose what I’m looking for overall is do I accept that I’m going to spend up to 8k to convert it to 6 speed manual overtime or is there other options ??

I know I could just go and buy a tt auto and not have such a headache I suppose and some money left and have some decent power however personally for me I do like this car in question ..

Im running 443 bhp with 433ftlbs of torque through my W58. I am relatively careful with it, I dont launch often at all, dont do burnouts. Saying that - I do put my foot down in all gears, and its been sweet as a nut. It makes a massive difference when the mapper takes into consideration the potential delicacy of the box. Power curve and delivery has to be just right to hold that power and not strip a gear.

I just did a simple fluid change on mine before turboing, hopefully entending its life a bit, every W58 has had a different life though. Its always the torque that kills the box. I would say to be safe keep it at the 400 ftlbs level and you can enjoy all the benefits of being turbo if you are sensible about driving it. Seen some others push the little W58 to quite a bit further than that!

I drove my W58 with different setups ranging from 250-350 ft.lbs estimated for a good 10'000 miles if not more. Then killed it once I went to the 450-470 ft.lbs region.

I've seen some boxes go with less torque, others with more. Impossible to say what they safe limit is. Reality is you may get lucky, you may not, either way it's a ticking time bomb.

Eventually you will want more power and that 58 is going to go bang. Most alternative gearbox solutions are going to set you back a few grand minimum, so it's a fair chunk of change to throw at it.

I've fitted and driven a number of manual boxes and I rate them as follows:

1. V160/V161 (obviously)

2. R154

3. 350z CD009 Nissan Gearbox

4. BMW gearbox swaps

There is also T56 conversion, but I've never tested one so can't comment on it yet.

You can't beat the original daddy v160/161 imo. The further down the list you go, the less oemlike the car feels and the more compromises you may have to make. But they are all valid options to replace W58

Thankyou for the reply both of you .. decisions to be made .. I think it’s fair to say it is a ticking time bomb especially when I will eventually want more power and seem almost silly to let it go bang when there is options there I have seen the bmw conversion kit however I like how you say in order how you rate them and that being at the bottom I mean personally I want it to have the oem feel and realistically I’m only going to get that with the v160 but that’s why it has the price tag .. I think if I go for the car then I will get it in to somewhere ASAP and sort of get the info on what it’s curretly running and look at keeping it to a minimum until a gearbox decision is made .. I mean I’m going to drive “carful” to an extent however of course I want to launch on occasions and have some fun and I won’t find it fun if the box goes bang because I’m already aware of that before even buying the car .. can either of you recommended a reputable/ knowledgable specialist who would be able to carry out a conversion to a different box ..