GTR Forum banner

1 - 20 of 33 Posts

·
Registered
Joined
·
115 Posts
Discussion Starter · #1 ·
Nice day everybody,

I'm interested on OS G close ratio gear sets, want some support. Car is used as a street racer with 600whp and PTE6466 .84 turbo, normally rolling from 40kmh to 700m distance.

1/ What's better and why, 1-3 + input shaft OR 1-5 + input shaft?
2/ Does the 1-5 come with 4th gear OR I get the 1-5 and put my stock gear?
3/ Do I need some other parts to do a proper swap?
4/ Who supplies the gear set with a good price?
5/ What would you recommend please?

I'd appreciate your support..
Ali
 

·
Premium Member
Joined
·
3,849 Posts
I built mine up with OS 1-4, billet centreplate, new bearings and synchros and had the gears REM finished.

4th gear is the input shaft effectively. Select 4th and the input shaft is locked to the main shaft and drives straight through at 1.00 ratio - most efficient gear in the box, lay shaft is bypassed.

OS 5th is lower ratio and good for top end acceleration but limits top speed to 180mph-ish. Stock 5th will run to over 200mph with a high rpm motor.
Stock 5th also better for motorway cruising.

You shouldn't need much else if yours is a late model 33 gearbox - early one may need some synchro parts and possibly reverse gear components. I built mine from a 32 box which needed a ton of parts from Nissan. I was lucky enough to pick up my new gearset and most of the synchros from Yahoo Auctions Japan for a bargain price.

I would definitely put new synchros and shift pawls whilst it's apart.

 

·
Registered
Joined
·
469 Posts
Not much I can add to that Lightspeed! :)

Regarding the 5th gear you can use a 1-4 Kit (OS) and use just a stasndard Nissan 5th gear giving the said 200mph top speed. If your box has never been re-built using the OEM modified 3rd-5th kit then you will need said syncros and baulk rings to make this work.

The OS Giken center plate is worth considering if you run 600hp as the torque pulls the two shafts apart the Billet OS keeps this in place.

Really strong kit as you would expect from OS Giken

Rich
 

·
Registered
Joined
·
679 Posts
im not sure tbh u need the getrag , the cross member then muck about with props irc then a 34 clutch as well am sure it prob work out about the same
 

·
Registered
Joined
·
115 Posts
Discussion Starter · #8 ·
Thanks for the replays folks..
I believe I'll need 1-4 OS + input shaft. Will keep 5th stock for top speed.

Regarding the 5th gear you can use a 1-4 Kit (OS) and use just a stasndard Nissan 5th gear giving the said 200mph top speed. If your box has never been re-built using the OEM modified 3rd-5th kit then you will need said syncros and baulk rings to make this work.
My box never been opened, when you say "make this work" does that mean that to fit the 1-4 + input shaft OS kit I will need syncros and baulk rings? Sorry but I'm not into transmissions that much.. One of the main objectives of the thread is to know what's needed to make the kit works (parts etc..), if somebody could list me the parts I would appreciate it..
 

·
Registered
Joined
·
1,313 Posts
whats the maintenance for the OS? does it need to be rebuilt every now and then even for fast street cars? getrag kit will cost around £5k including nismo clutch from nengun/rhdhapan if im not mistaken, so i guess OS is cheaper depending on its maintenance?
 

·
Registered
Joined
·
115 Posts
Discussion Starter · #11 ·
hi guys,
I have by now the OS 1-5 gearset + inputshaft + center plate. I also have baulk rings, countershaft bearings, needle bearings and some other stuffs. I'm looking now for the synchros which I can source. Could you guys please help me what do you I need else? I think there are other types of bearings and seals I read somewhere ... Any help would be appreciated..
 

·
Registered
Joined
·
3,585 Posts
ive had a route 6 3 speed which is virtually identical gearing to os 3 speed, and id much prefer a getrag 6 speed personally.

1st gear was massive on my route 6 to big imo.
 

·
Registered
Joined
·
115 Posts
Discussion Starter · #14 · (Edited)
Hello everybody,
I started working on the 1-5 OS kit. I have a problem currently, I would appreciate if someone could help. My mechanic is saying that there is a difference between the synchro sizes, see pics below. Anybody knows where can have these? I bought all stock synchros from rhdjapan, this one though I don't know where to get from. I'm assuming this is a GTR33 box I hope I'm not wrong, we installed everything except this synchro I'm asking about. The new shaft is on the left without a synchro, the stock shaft is on the right with the synchro. The stock synchro doesn't fit the new shaft.





 

·
Premium Member
Joined
·
3,849 Posts
Maybe your old box was Auto Gallery Yokohama modified?

They machine the gears and use multi part synchros for a better shift.
 

·
Registered
Joined
·
5,346 Posts
OS 1-5 is the best mod I've done on my car.
The long first gear is perfect for big turbo cars and is great for launches and keeping the car on boost
 

·
Registered
Joined
·
115 Posts
Discussion Starter · #19 ·
OS 1-5 is the best mod I've done on my car.
The long first gear is perfect for big turbo cars and is great for launches and keeping the car on boost
Great. I have been thinking to increase my turbine housing size (currently 0.84) since as you mentioned that the long ratios help spooling and having big turbos. What's your turbo set up and what power you have please? On my PTE6466 0.84 I guess it would be fun to drive though.

For my issue above, my bad I missed getting the 4th gear synchro (32604-40P61).
 

·
Registered
Joined
·
672 Posts
How many whp you are going for? And which clutch are you gonna use?

I got an rb30 with a pte 6266 gen2 and looking for drivetrain option at the moment.
 
1 - 20 of 33 Posts
Top