Os Giken R33 box or Getrag 6 Speed?

[skylion]

Hi,

Just got back from Santa Pod on Monday and lost 5th and Reverse gear. Running about 650bhp, so figured it wouldn't take long till the gearbox shat itself.

Have two options:

(1) buy OS Giken internals and get my R33 gearbox rebuilt
(2) buy an R34 6 Speed Getrag

I know I have to change clutch and few other bits. Bit unlucky as I just put a brand new Exedy Triple Plate in my car so bit frustrating since I'm going to have to buy another triple for the R34 box. So that's additional cost.. but then again so is getting the R33 gearbox rebuilt anyways.

opinions pls?

[xaero1]

From what I understand the Getrag 6 speed box isn't as strong as people often think. You're probably far better off with OS Giken internals.

[edit] In fact, speak to RB Motorsport as I understand they are the official UK OS Giken supplier.

[plkettle]

I heard that you have to rebuild the os giken box every 10,000 miles or so ?
less if you are dragging it...

too expensive for me to be doing that and its a shame as the box is the only thing keeping me at this power level.

[hockey-boy]

i am using getrag 6 speed in my 32 and it's running mint.
iv'e had no issues with it in my 32 and it is taking a beating.
i know a few others use them in there 32's and 33's and they havent had any issues as far as i am aware

plus with the price of a giken kit fitted etc you can buy a 6 speed for a lot less

[skylion]

Does anyone know what the 6 speed box can take BHP wise?

Thanks
Shah

[hockey-boy]

dont know what it can take but i am running 600 with 500+ ft torque and its taking that ok

[blue32]

Sorry if this is off topic, but is putting a 34 Getrag into a 32 alot of work?

Cheers

[GT-R Glenn]

I heard that you have to rebuild the os giken box every 10,000 miles or so ?
less if you are dragging it...

You are talking sequential I think
The aftermarket OS gearkit to fit the R33 box should last as long as any other standard R33 box.
Its a helical cut sychro gearbox, quiet and take heaps of power.

[GT-R Glenn]

Gear Type 6 Speed Manual
Final Drive 3.55:1
1st Gear Ratio 3.83:1
2nd Gear Ratio 2.36:1
3rd Gear Ratio 1.69:1
4th Gear Ratio 1.31:1
5th Gear Ratio 1:1
6th Gear Ratio 0.79:1

First gear is pretty much a waste of time, and you might want to change the final ratio in an R33
I wouldnt, but I wouldnt run the 6 speed either.

[skylion]

Originally Posted by GT-R Glenn

Gear Type 6 Speed Manual
Final Drive 3.55:1
1st Gear Ratio 3.83:1
2nd Gear Ratio 2.36:1
3rd Gear Ratio 1.69:1
4th Gear Ratio 1.31:1
5th Gear Ratio 1:1
6th Gear Ratio 0.79:1

First gear is pretty much a waste of time, and you might want to change the final ratio in an R33
I wouldnt, but I wouldnt run the 6 speed either.

What would you recommend?

[GT-R Glenn]

OS Giken helical gearset in your existing case.
The only thing to consider is if you want a 1 to 3 set or a 1 to 5, the aftermarket option for 5th is less tall than the standard, so you pull about 3200 @ 100 k instead of 3000 @ 100 k.
In reatlity all that means is with the different 5th gear you cant do 300kph anymore and it revs slightly harder at cruising speed.
Unless you can pull 9600 in top ....
I cant.
I paid 3400 NZD for my 1 to 5th kit including massive input shaft.
Including new bearings etc: and fitting to the car was about 5000 NZD
A cheap bullet proof quiet gearbox that will take 700hp all day and has nice ratio's.

[95GTR600]

Originally Posted by skylion

Does anyone know what the 6 speed box can take BHP wise?

Thanks
Shah

I want to know also before rebuild (os giken) or convert my R33 to a Getrag... any help ?

[pupsi]

Go for the OS Giken internals.

[skylion]

I'm running Getrag 6 Speed now, I had MIJ Performance install the gearbox, driveshafts etc. I'm running 780 BHP (Fly) and have had no problems. The gearbox is really solid and speaking to over GTR owners they seem happy with the 6 Speed Getrag.

Supra's run the same box with over 1000bhp.

I rang up and got a quote for rebuilding my gearbox plus OS Giken internals and it was almost £5k with labour, the 6 Speed was much cheaper and having 6th Gear on the motorway means I can cruise at 100mph around 4k RPM and not use my turbo which saves me money in Fuel.

Give Hom @ MIJ Performance a ring, he has two R34 boxes, and one is going into a project car he's building so I'd get the other one before it gets sold as they are quite rare to find...

Cheers

[Tim]

Originally Posted by skylion

the 6 Speed was much cheaper and having 6th Gear on the motorway means I can cruise at 100mph around 4k RPM and not use my turbo which saves me money in Fuel.

Cruise rpm will be higher for the same speed using a Getrag unless you change to R34 diffs.
I'd go with the OS Giken.