Ultimate strength of Getrag 260 box from 325?

[alistairolsen]

Has anyone ever broken one of these boxes, and in what circumstances?

Im really wondering how much torque they will cope with for a fair amount of time, and what happens when they fail.

Anyone running torbo engines in excess of 300lbft on this box?

As an aside, does anyone know how the ZF box from the E36/E34 compares?

Cheers

[leeparkes]

ive never heard of one fail!
(im sure someone will be along to prove me wrong)

[Gunni]

http://www.miloop.se/film_view.aspx?movie=7550

2007-09-11 Bromsning av världens starkaste M20Turbo
1090 Hk och 1193Nm vid 6400 Rpm & 2,8 bar

that´s almost 1100hp and 1194nm torque, 2,8 bar boost.

your box is not going to fail ;)

[alistairolsen]

http://www.miloop.se/film_view.aspx?movie=7550

2007-09-11 Bromsning av världens starkaste M20Turbo
1090 Hk och 1193Nm vid 6400 Rpm & 2,8 bar

that´s almost 1100hp and 1194nm torque, 2,8 bar boost.

your box is not going to fail ;)

are you 100% sure thats on the original box? Id have thought its extremely unlikely....

[Jhonno]

http://www.miloop.se/film_view.aspx?movie=7550

2007-09-11 Bromsning av världens starkaste M20Turbo
1090 Hk och 1193Nm vid 6400 Rpm & 2,8 bar

that´s almost 1100hp and 1194nm torque, 2,8 bar boost.

your box is not going to fail ;)

are you 100% sure thats on the original box? Id have thought its extremely unlikely....

Why?

[alistairolsen]

well with 1000bhp virtually any performance car will need the gearbox either replaced or modified. If it is the original spec box unmodified then its genuinely amazing!

[Jhonno]

it isn't bhp that kills boxes

[alistairolsen]

no, its torque and that cars making 1100 Nm of that too!

I just want to know if that car is really running 1000bhp and 11Nm thru a box from a 325?

And what anyone else has found using these boxes with turbo conversions and suchlike?

[alistairolsen]

As an aside, does anyone know how the ZF box from the E36/E34 compares?

[Jhonno]

Going by your logic the ZF box wouldn't stand up to it anymore than the Getrag box..

[alistairolsen]

Going by your logic the ZF box wouldn't stand up to it anymore than the Getrag box..

will you stop being argumentitive just for the sake of it!

I merely asked for confirmation that car was actually on a getrag 260 and commented that most other performace cars approaching that level of power require fairly hefty transmission modifications.

If the 260 is really that good then thats ideal! I happen to have the ZF box mentioned lying and I just thought Id ask if that too was immensely strong.

[zaust]

Kinder's is running 260 nm and is a standered box from an m20b20, No problems as yet and no whines.

[Jhonno]

Going by your logic the ZF box wouldn't stand up to it anymore than the Getrag box..

will you stop being argumentitive just for the sake of it!

I merely asked for confirmation that car was actually on a getrag 260 and commented that most other performace cars approaching that level of power require fairly hefty transmission modifications.

If the 260 is really that good then thats ideal! I happen to have the ZF box mentioned lying and I just thought Id ask if that too was immensely strong.

I'm not, but you were saying you don't think a factory box would take the power.. A ZF is still a factory box..

You have a video of a 1100nm car running the standard box...

I have heard of no Getrag's failing under boost

[alistairolsen]

Going by your logic the ZF box wouldn't stand up to it anymore than the Getrag box..

will you stop being argumentitive just for the sake of it!

I merely asked for confirmation that car was actually on a getrag 260 and commented that most other performace cars approaching that level of power require fairly hefty transmission modifications.

If the 260 is really that good then thats ideal! I happen to have the ZF box mentioned lying and I just thought Id ask if that too was immensely strong.

I'm not, but you were saying you don't think a factory box would take the power.. A ZF is still a factory box..

You have a video of a 1100nm car running the standard box...

I have heard of no Getrag's failing under boost

No, I have a video os an E30 on a dyno and someone suggesting its still on the standard box, hence asking for confirmation.

I dont want to run 1100Nm, so whether or not the ZF would take it isnt the question.

I want to know if the car in the video was running a getrag 260, and if that is demonstrably that strong, is the ZF as, or close to as strong?

[Turbo-Brown]

Someone mentioned that the 'box from the E34 525tds (not td apparently!) is beefier than the E30 'boxes and popular for drag racing somewhere or other.

Can't really remember now, just went out and bought one anyway

[Morat]

I think you're only addressing one half of the problem. Surely to make a valid comparison you need to know how much traction these cars have? a 325 will spin up the rears in the dry atleast in the lower gears and if you don't change the wheels/tyres/suspension to give more tractopn then you'll only be achieving the same levels of torque.
Unless I'm wrong of course

[Turbo-Brown]

Interesting one that!

If we were to take a snap shot of a car doing a nice steady burn out, the torque going through the drive train would be proportional to the amount of force the contact patch of the driven wheels (and the radius of those wheels) was applying to the tarmac.

However, that amount of torque being applied by the engine will have been arrived at by trial and error of the driver's foot.

It is still possible to apply the engine's full torque (multiplied or divided by the gear ratios of the 'box and diff) to the driven wheels, even if there's no traction as that torque will be being used to overcome the inertia of the wheels and other rotating components (brakes, prop.......etc.) The only thing that stops that maximum amount of torque being sustained through the drive train is the fact that, without traction, either the driver lifts the accelerator, or the rev-limiter cuts in.

so yes and no, and my explanation almost certainly sucks too so apologies for that too!

[alistairolsen]

I completely understand what youre saying and im aware of this, but Id be using the box in a lighter car, soo if it survives at 350bhp in a three series then it will survive in my application!

[e30_Turbo]

Mines a stock getrag and has had well over 300/300 shoved up it for 3 or 4 yrs now, 163k too, it works as it should but has got noiser over the last 6 months tho, more because I've upped the boost a little, it gets taken too it's limits atleast once a week

Limmets budget build video, shows some of the work involved:

http://www.miloop.se/film_view.aspx?mm=1&movie=5726

[ShakeyC]

In simple terms you can apply as much torque through the box as you like but the wheels will just light up, when wheel spinning there is much less resistance therefore torque will just be wasted away into tyre smoke. Your biggest issue would be the clutch then tyres then maybe prop or half shaft failures.

[Colonel Sanders]

Im pretty sure limmets gearbox was a zf from what i was told on ppf. The say standard is good for up to 500ft/lbs torqe on a good box. A 525tds box with e36 328 prop and e28 m5 diff is about the best bang for buck set up you can get. But some mods are needed to fit the diff.

[Gunni]

The limit in E30 drivetrain is the half shafts snapping when your dumping the clutch with massive slicks in the back and 1bar+ already boosting via launch control.

[Colonel Sanders]

Very true. You will do a half shaft before a box if you launch hard. Im replacing mine with ones from ppf, they can twist around 1 an a quarter times on a hard launch.

[Simon13]

So really from reading this the drivetrain in a 325i is pretty heroic and laughs at what a 325i can throw at it!

[e30bmlover]

http://www.miloop.se/film_view.aspx?movie=7550

2007-09-11 Bromsning av världens starkaste M20Turbo
1090 Hk och 1193Nm vid 6400 Rpm & 2,8 bar

that´s almost 1100hp and 1194nm torque, 2,8 bar boost.

your box is not going to fail ;)

jesus! thats some poke!

[alistairolsen]

so in a 550kg car on 8 inch rear slicks and assuming the rest of the drivetrain is ok, the 260 box would survive 400bhp and 300ftlbs torque ok?

[Gunni]

yea without doubt.