Gearbox power rating

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Hoobs
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Post Sat Apr 28, 2012 11:42 pm

How much power can a 325 gearbox cope with safely / regularly?

I have my old 323 box mated to an M52 with an uprated paddle clutch. I also run an e12 LSD.

I'm wondering if the box will be able to cope long term??
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mrLEE30
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Post Sun Apr 29, 2012 5:50 am

Getrag 260 can cope with 260N/m the 240 can handle 240.

These are the standard m20/10/40 boxes. M3 had a 265, you can guess the power handling ability of that!!
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Hoobs
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Post Sun Apr 29, 2012 7:09 am

Every days a school day. :teehee:

Thanks.
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Simon13
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Post Sun Apr 29, 2012 11:11 am

the 260 boxes can take way more as can the 265's. 240's wont
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e301988325i
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Post Sun Apr 29, 2012 11:18 am

Simon13 wrote:the 260 boxes can take way more as can the 265's. 240's wont
I'm sure I read they can reliably long term take +50% of their rating so 390 Nm = 288 lb/ft!
I said:

Can anyone suggest how to test if the boot lights are staying on with the boot shut?

e30topless said:

lock the wife in there
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mrLEE30
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Post Sun Apr 29, 2012 4:01 pm

i am sure they can, but that is their rated maximum torque capacity
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bss325i
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Post Sun Apr 29, 2012 5:56 pm

mrLEE30 wrote:Getrag 260 can cope with 260N/m the 240 can handle 240.

These are the standard m20/10/40 boxes. M3 had a 265, you can guess the power handling ability of that!!
265 NM = 195.45lbft.

An M30B35 of which a getrag 265 is often mated to is rated at 225lbft which = 305NM.
http://www.bmrperformance.co.uk

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Andyboy
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Post Sun Apr 29, 2012 9:44 pm

The 240/260 numbers don't really mean anything. They are just codes for gearboxes. The 265 is merely a five speed version of the four speed 262 and the 245 was somewhat weaker than the 240. Almost all E36 325i's used the Getrag 250 without issue.
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randomspeedfreak
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Post Mon Apr 30, 2012 10:40 am

what can an is box take?
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mrLEE30
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Post Mon Apr 30, 2012 1:15 pm

Andyboy wrote:The 240/260 numbers don't really mean anything. They are just codes for gearboxes. The 265 is merely a five speed version of the four speed 262 and the 245 was somewhat weaker than the 240. Almost all E36 325i's used the Getrag 250 without issue.
I was sure that the 240 and 260 were their rated allowable torque, Getrag even today follow the same practice on thier manual gearboxes...

http://www.getrag.com/en/214.1?_search_ ... _offset_=0

but as everyone correctly says they will handle more torque, but it will affect the life of the gearbox.
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Steve
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Post Mon Apr 30, 2012 1:25 pm

A lot of the turbo boys are making big power with a standard gearbox the issue is normally more to do with the clutch.
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e301988325i
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Post Mon Apr 30, 2012 8:57 pm

randomspeedfreak wrote:what can an is box take?
Not only having been hand crafted by god himself but also galvanised, I think it could take 150% of it's infinityNm rating.
I said:

Can anyone suggest how to test if the boot lights are staying on with the boot shut?

e30topless said:

lock the wife in there
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ross_jsy
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Post Tue May 01, 2012 1:17 am

Steve wrote:A lot of the turbo boys are making big power with a standard gearbox the issue is normally more to do with the clutch.
Was told by the guys on e30 tech that the drive shafts will let go before a 260 normally. Pretty impressive stuff really
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