What gearbox for my S14 - want to eventually run 450-500BHP

[greenmachine282]

Hi folks. I have been running my S14 at 382bhp @ flywheel for quite some time now.
Unfortunately i have managed to snap my gearbox output shaft completely renderring the gearbox U.S.

I plan to eventually run 450 to 500BHP but need guidance on what gearbox i should put in to be able to cope
with those figures. Also i have an ACT heavy duty paddle clutch that tops out at 463lb/ft. Will i need to replace this to
make the gearbox change and is it compatible if i do not upgrade engine straight away but install the new gearbox to get back on the road.

Any help will be much appreciated
Jason

[-ghost-]

Z33 350z box?

[Actual_Ben_Taylor]

Z32, R33, Z33, OS Giken, PPG...

Depends how much you want to spend.

[greenmachine282]

I do not really want to go above a grand if i can help it.
I know the z32 box is solid and quite easy with an adapter plate kit.
Z33 box is a 6 speed isnt it? how easy is it to get this in expect it will cost way
more than a grand anyway.

[-ghost-]

a grand all in will make it much harder

id still go for a z33 but you going to have to hope you can find the bits second hand as its quite involved like the z32

not sure if its ever been done(or done right) but I know a lot of people are using the bmw boxes cant think ive seen a sr with one but if you give nev at f1 moto a call I bet he could give you some answers

[zeppelin101]

An OSG 3 gear kit plus main shaft is £954 on RHD Japan with shipping thrown in - plus costs for a box rebuild.

Z32 boxes seem to go for ~£500? If you wanted a kit to convert it to the SR then Mazworx sell one which is around £500 all in + shipping and taxes.

You might scrape a Z32 box for a little over 1k but depends how much you have to pay in taxes and any machining.

[jumpbike]

I've got an RB25 box, same as Z32 just different adaptor plate, got ACT Xtreme 6 paddle clutch, was running 480hp, all fine

[sparky_s13]

Dont changing the box mean custom prop and gearbox cross member?

Dont see why people go through all that effort when you can get OSG gear sets (I believe they are made to order and take a few months) but it seems the easiest option to me and what I would probably do if my box ever went (435hp/440ft lbs)

[Galant_X]

Dont changing the box mean custom prop and gearbox cross member?

Dont see why people go through all that effort when you can get OSG gear sets (I believe they are made to order and take a few months) but it seems the easiest option to me and what I would probably do if my box ever went (435hp/440ft lbs)

No matter what gear set you chose, its limited by the physical dimension available within the original gearbox. Why pay big money for a gear set that may hold, when you can fit a z33 or 32 gearbox that takes more torque then you ever are gonna produce with a SR20DET?
If you are able to do most of the work yourself, the total cost should be similar for both cases.

[-ghost-]

People have had os boxes fail its normally due to other stock nissan parts tho

the size difference between a sr box and a z33 is huge

[jumpbike]

The Z32/RB25DET boxes just happen to bolt up into position perfectly with the right cross member, just need the first half of the prop custom which isn't expensive if you have both parts and can fly a tape measure.

I've just got a cranked shifter as the RB one is further forward so ends up in the dash. 5th gear ratio is mega long though so have an auto 3.9 diff which makes it drive as if its still got the SR box in and speedo reads bob on

[Random Tim]

The Z32/RB25DET boxes just happen to bolt up into position perfectly with the right cross member, just need the first half of the prop custom which isn't expensive if you have both parts and can fly a tape measure.

I've just got a cranked shifter as the RB one is further forward so ends up in the dash. 5th gear ratio is mega long though so have an auto 3.9 diff which makes it drive as if its still got the SR box in and speedo reads bob on

Same here. Polo fitted it with one of his adapter plates and supplied the box and modified prop for £1k all in. That was a few years ago and I don't know if he still offers this service. I need to make a new cranked shifter though and change the diff. 5th is a bit long as said above on the standard. Got a 4.3 at home though

[greenmachine282]

Thanks all for your help. I know 1k is optimistic but i dont want to go crazy is all.
Looks like i may have to go the z32 option as seems the easiest next to new gear set.
Really unsure if i want to reuse the standard box as ive lost faith as i snapped the output.
The car is not being repaired for quite some time as i just got married.
Just need the info so if i see a box i need in the future i will get it.
Thanks for your posts.


*One S14 owner seriously missing his toy*

[ANDY black s13]

I have been looking into doing a box swap/or the OS giken gearsets as an option,as my intended set up will destroy a stock box
and imo the 200sx box is flawed and will never be able to cope with large powers for long
3rd gear is lacking in bearing support (I read some were) so will always be the weak link so to speak
read the z33 early pre 03 box's have problems,later ones are better,but not a lot of info regards power and lasting
so not turned onto that idea personally, six cogs is nice (if the ratios are good) but if the box has issues it's not worth considering imo
were as the rb/z32 box is well known to handle loads, many swedish drag cars @800whp+ z32 box survives full power launches on slicks
so thats the route I'm going as a long term solution
there may well be other stronger box's but if needs more £££'s invested over the z32 costs to get it fitted is it worth the bother
maybe if the ratio's would work out better,and/or it was six speed could be an advantage over the z32's ratio's
5th at 0.750 is pretty tall,bit of rev drop from 4th, but can pull a high top end if you have some power
just my 2p opinions mostly based on performance per £ on average parts costs
driveshafts become the next weak link

[Drifter]

Dont changing the box mean custom prop and gearbox cross member?

Dont see why people go through all that effort when you can get OSG gear sets (I believe they are made to order and take a few months) but it seems the easiest option to me and what I would probably do if my box ever went (435hp/440ft lbs)

The really long 1st gear in the given set is what put me off, plus as has been said they have been known to break at a not what I'd call high power.

[greenmachine282]

Thanks Andy, so in your opinion z32 overr OSG gearset? As this will be the setup im considering. Will the rb gearbox need machine work like the z32? And is the Z32 the most favourable out of the too?
Thanks for the replies

*One S14 owner seriously missing his toy*

[Jordan_200sx]

Z33 boxes are considerable bigger and more durable than an RB/Z32 box. Early boxes suffer from a sincere issue which causes premature wear, with the later model (CD009) having the revised triple syncro's so to speak of.

If your budget is £1000, i'd personally write the Z33 conversion off. Im currently doing mine amongst a full engine build, and it has been far from cheap to do. Even RB & Z32 boxes have begun to creep up in price these days, but a box conversion is a much better solution than putting a gear set into a small casing gearbox (SR)

[def]

The os g kit is what i would do. The ones that break are nissan parts not the os g kit. Seen them run 600 plus

[Richie200sx]

My Cd009 box cost me £800 18 months ago, to put it into context.

[jumpbike]

I paid little over a grand for my RB conversion, including 2 gearboxes, adaptor plate, slave cylinder, modified short shift, custom front prop half, and auto diff.
Just see what comes up for sale, make a wanted post, Bargains pop up