Any knowledge about old BMW transmissions?

Completely aside from and unrelated to BB-Q's post asking about BMW 6 speed conversions, I was wondering if anyone here has any experience or knowledge about older BMW transmissions that were attached to M30's and the kind of abuse they can take. G260/6, G265/6, and the like. I know this isn't exactly the forum for this question but I struck out on the appropriate ones so I figured I would ask here as well, just for giggles. If it makes any difference, this is relevant because it's for an engine that's going into a Volvo. That counts, right?

Any help is appreciated, thanks!

EventuallyAyrton said:

Completely aside from and unrelated to BB-Q's post asking about BMW 6 speed conversions, I was wondering if anyone here has any experience or knowledge about older BMW transmissions that were attached to M30's and the kind of abuse they can take. G260/6, G265/6, and the like. I know this isn't exactly the forum for this question but I struck out on the appropriate ones so I figured I would ask here as well, just for giggles. If it makes any difference, this is relevant because it's for an engine that's going into a Volvo. That counts, right?

Any help is appreciated, thanks!

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The Official Party Line of TB Performance is they are good for minimum SIX THOUSAND N/M of raw torax.

Indestructible....
Volvo used them on the Grope A cars so maybe 1 million ft/lbs

Of course TB performance party line ignores totally that the model used in Group A cars--which used the exact same rations as the GpA Touring Car BMWs, the Rover V8, and the car that swept away all the others, some Ford thing all used a different gear set with a 2.37 first gear ratio

Now we know from the charts on T5 that the torque capacity of a given box goes UP as the ratio from clutch input shaft down to bottom/cluster gear goes up---and with that 1st , 2nd and 3rd.
And as the input to cluster ratio goes down and first ratio goes down into ratios suitable for a pick up truck, the torque capapcity also goes down..

So a Getrag with a 2.37 first is one thing, and its GOOD

And a Getrag with a 3.97 or 4.25 first is a pile of poooo in terms of strength..

Add to that the HUGE annoyiance in splitting the case, the absurd prices for what few parts that can be had and its a disaster of a gearbox.

If in good shape the 260 or 265 can take up to 500hp, but then they start to break. Peter broke a couple in his race car then finally upgraded to something stronger. His guy who rebuilt his last one told him to make it last add a tranny cooler. He didn't and broke it racing around PIR. I think his 8v redblock is putting out close to 600hp now is why he upgraded the trans, plus as stated cost a bunch to pay someone to rebuild them. I got a rebuilt 265 to put in my 16v turbo race car with twin disc quartermaster. Scored it for $50 on craigslist in a crate, plus I already had all the getrag adapters and driveline and stuff for a 740 from my old race car that the stock dog dish flywheel exploded on. 3.31 is the tallest ratio that I can get for the stock rear end so I run that for now with it.