M42 weaknesses discussion - idler gear & oil pump

[dsm2002]

I am hoping Tim S and Andyboy will pop into this thread. In light of the discussions about the weaknesses of the Ratch's thread, specifically the idler gear and the oil pump. Advice is that this is improved in the M44.

I am building a 2.0 litre M42 with a 88mm M47 crank. I have 34mm inlet valves, 31.5mm exhaust with 6mm stems, Catcams 290°/275°, shim under bucket cam followers (Eurospec), E36 M3 ITBs. Max revs will be around 8500. The head is being modified by a chap at the moment.

I have already purchased new timing and oil pump parts, including the idler gear/deflection wheel (part no 11 31 1 727 569) and oil pump/set rotor (part no 11 14 1 714 611). What's the failure point with these?

About the oil pump, my initial concern was that it seems to meagre. I had a chat with the engine builder (no experience on BMWs, heaps on Nissans, etc) and he thought the M42 oil pump would be fine from the point of how much oil he'd expect it can supply.

I want to keep it under 2.0 litre and will use 85mm or possibly 85.5mm pistons (the class allows for 2.0 litres + 4% oversize).

The thing is that I need to keep the M42 block. Can these parts be fitted to the M42 timing case? Can I fit the M44 front bits be fittred on the M42 block?

[dsm2002]

I have looked through the parts listing. It seems I need the following parts to adapt the later rail and M44 oil pump to the M42. Correct?

Lower timing case 11 14 1 739 800
Gasket Steel 11 14 1 743 032
Guide 11 31 1 734 694
Fillister head with washer 07 11 9 920 161
Deflection rail 11 31 1 739 130
Fillister head screw 07 11 9 919 824
Chain tensioner 11 31 1 743 262
Bush 11 31 1 247 452
Hex Bolt 07 11 9 904 533
Flat Washer 07 11 9 900 052

Set rotor 11141714611
Oil pump cover 11141714613

[rix313]

When I build up my engine (not a 2.0L but an M42/M44 combo) I'm planning on using a later M44 front timing case which has a guide as opposed to the idler sprocket. As far as I can certainly tell all the cases and covers are the same between the M44 and M42; with the exception of a couple of alterations due to sensors or breathers being in slightly different locations etc.