[Russ Noble]

Well, Lim has undertaken to cast the sump (as well as doing the majority of the machining required for this build). There are several criteria for this sump...
1 I want to keep it as shallow as possible.
2. It needs to allow the use of a LHS front mounted 928 starter to work on the small 930 ring gear.
3. Because there is the thought that we could possibly sell a few of these precision made kiwi castings it needs to accomodate the largest stroke possible bearing in mind the other criteria.
4. It must clear 4 bolt caps.

So the mounting of the 928 starter is the limiting factor and Lim has decided to make a mockup of the rear section of the sump in perspex so we can see and measure the clearances that we have before making the actual pattern.

We are aiming for a wall thickness of about 6mm, any thicker is too heavy and any thinner makes it difficult for the molten alloy to flow satisfactorily.
So the actual pattern is going to be crafted in 1/4'' steel plate. It looks as though we can build this sump to accommodate 4.1, maybe even 4.25, strokes, depending on components used.

Below are some shots of the perspex mockup, the actual full pattern will of course have radiused corners etc where required.