As both the 4.4 and 4.6 bellhousings are machined from the same casting, if you’re unable to source a 4.6 bellhousing it may be possible to find a machine shop that would machine down the radial stiffening ribs on your 4.4 bellhousing to provide sufficient clearance for the larger L51 converter. I think this would be a worthwhile upgrade if you get the opportunity to source an L51 converter from somewhere.





The 1058 000 035 5HP24 model for the 4.8 E39 Alpina B10 & E52 Alpina Roadster also used the larger L51 converter, but these were produced in much smaller numbers than the 4.6is.

Phil