[N0OS3]

I'll update this OP with anything i find from searching:

SOLUTION!

As far as i understand it's made by GM... as far as American Made models, the transmission ID is as follows:
(Thanks to eNineZero)
323i : ZF 6HP19Z
325i : ZF 6HP19Z
328i : ZF 6HP19Z
330i : ZF 6HP19Z
335i : ZF 6HP19Z

323i LCI : GM 6L45R
328i LCI : GM 6L45R
335i LCI : ZF 6HP19Z
335d LCI : ZF 6HP26Z (443 ft/lbs)

Similar model (6HP19A) of transmission was used in the 2003-2008 Audi S4's

Also According to ZF's catalog the 6HP19/6HP21 transmission has a 258 ft/lbs to 295 ft/lbs input torque rating which is model specific.

So LCI non-turbo 3-series seem to use a GM 6L45R transmission, the 335d uses the ZF 6HP26Z and all other models use the same ZF 6HP19Z transmission (In the US and Canada).

Manual trans have Flywheel upgrades, 4-puck or 6-puck (racing clutch), SSK, and tons of options for withstanding high horsepower output, quicker shifting, and a bunch of other things.

I'm bringing up this thread based on reading other posts and threads about increasing performance on the 320i-330i transmission(s) supposedly only rated for 290BHP... i'm not sure if this is completely true but from ARMA's occasional testing they have broken a few transmissions from supercharging their engines... **according to thisN54tech.com article the 2006 N52 and N54(built in 2006) have the engine listed above; the TORQUE CONVERTER is rated for 400nm or 295ft.lbs tq. For the -35i models, they have the ZF 6HP19ZTU (or technically updated), i haven't found a torque rating for this 'TU' tranny yet but i'm sure it's well over 400ft.lbs.tq.

...is there anything that's possible to beat this? Valve body converters(for 'Semi-Automatic transmissions)? Shift kits? Upgraded Torque Converter?

So... my conclusion is that unless someone mass produces a stronger material torque converter for this transmission (to keep the prices low for consumers vs custom work) in addition to the foreseen labor costs, it may be beneficial to just buy a 2007-2010 steptronic transmission from a 335i (seen on Ebay for $3,500-$5,000 from the notorious vendor "BavarianAutoRecycling.com")

**i still have my M5/M6 7DCT sitting at home but the fitment is not looking too good from what i'm told... a custom center console would be the minimum requirement which is like $2k worth of restyling on its own.**

[N0OS3]

**bump with updates**