Os Giken Cross Mission Gear Set + 700awhp + 1/4 Mile Work

[James_03]

Hey guys,

Have a r32 gtr with a 26/30 engine running e85. Currently running 620awhp on 25psi, going back for a retune for 30psi and hopefully 700awhp.

Now I need to do something with the transmission, looking at doing the following:

OS giken 5spd gear set

Billet OS centre plate

OS input shaft.

Triple plate HKS clutch

Associated 09/97 r33 gtr gearbox synchros and misc parts

Now I would like to do some quarter mile work, not every single week, but I would like to go on occasion. I would like to hear from people with similar power that have done 1/4 mile work with this gearset? Or for that matter, people that have this gearset with xyz power? What exactly is it capable of?

I know street it should be fine, but we all know the strip is where it all turns to tears.

Cheers.

[Piggaz]

Well they're rated at 800 HP... Apparently.

I busted my OS 5 speed with 630 WHP (2.8 and -5's). It looks like either bent or broken a tooth in second.

With 700 WHP and an RB30, I'd be looking at something else IMO.

[James_03]

Yeh that's what I was thinking too Piggaz, I think I should be looking at something else esp with the additional torque from the 30. Just weird because I have read reports over on the gtr uk forums of people running some pretty crazy power through them, ie 900hp, and doing 1/4 mile work too with no issues. By biggest gripe with the OS gearset is that is uses standard nissan synchros still, which I am led to believe are pretty average.

If you don't mind me asking, did it break on the strip or street at that power level?

[Piggaz]

Busted on a track day running roughly 550 whp at the time. Now, I'm not sure if the damage was done prior or I did something that day. Maybe a shock load over a ripple strip. I haven't pulled it down to have a look yet. The new box should be here soon so I'll know what failed soon enough.

There is a bloke in WA that has busted two of these OS sets with a 2.8 and low mounts also.

After 12 months of research, talking to guys and manufacturers of gearsets, I chose the OS88. Yes, it's a lot of coin, but good luck breaking that.

By the time you do a PPG 5 speed for example with all th fruit you're almost at a 6 speed sequential anyway, AND you're not still dealing with the stock gear case.

Food for thought?

[James_03]

Yeh I hear ya man, the OS88 does actually make sense if you consider the cost like you said to go through a few OS gearset rebuilds. I just love how OS pull that magical 800hp number for the gearsets, not that they have probably refunded a single person that has broken one under that figure lol.

I have just been lunching 3rd in standard boxes so far (also track work), which is bad, but doesn't hurt nearly as much as what an OS gearset would financially. I seem to find that its also heat related, as I had 2 boxes let go right at the end of a session just as it was about to end.

Both running redline fluid too.

I might just have to park it up for a while, and save like crazy for the OS. I like the fact that the OS88 runs helical gears too.

Did you consider the hollinger box at the time Piggaz?

[Piggaz]

I considered everything mate. I went for a run in an R34 GTR with a OS88 and my mind was made up by the time we got to the end of the first street.

The holinger was alot more $$ again. I got everything I needed with the OS 88 including a new clutch and one of the option ratio sets (extra cost) for a tad over $16k delivered.

They Definately as "agricultural" as you would expect.

[James_03]

OK cool, thanks for all the info mate.

I think it's probably wise to just save and go the OS88. I can't justify the cost to build a PPG or OS gearset based box that might or might not take the power, which is what I seem to be reading everywhere, especially with some 1/4 mile work chucked into the equation.

Probably have to get used to the taste of canned baked beans for a while lol.

Cheers.