View single post by Judson Manning
 Posted: 09-22-2006 02:07 pm
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Judson Manning



Joined: 03-14-2005
Location: Atlanta, Georgia USA
Posts: 406
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 I figured you had a good reason for not running the dry-sump.  They are expensive and do take up a great deal of room.  And yes, my wife has informed me my racing budget has been spent for the year as well!

One strapping plate option is to sandwich a new plate between the lower bearing panel and the sump.  This adds depth to the sump (which may be a good thing), but the further you get from the journels, the less impact such a plate will have.

The increased distance from the journels is just one reason why I suggest 'making room' for the 10mm plate by milling the lower bearing panel.  In the end, I think the S4 block has plenty of rigidity without such a plate.

The top plate is actually an segmented insert that fits between the block and the liners.  The idea is to transform the Lotus block into a solid chunk of aluminum thereby eliminating any flex at the top of the liners.  As you've pointed out, removing the liners at some time in the future is now impossible.

As long as your engine builder remembers those locating dowels, I don't think the top plate is necessary.  If you are using over-bore pistons and/or pistons with an upper crown, a typical modification is to chamfer the top of the piston.  This gives more piston-to-wall clearance where the piston comes in close contact to the head-gasket.