View single post by Judson Manning
 Posted: 12-01-2008 12:38 am
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Judson Manning



Joined: 03-14-2005
Location: Atlanta, Georgia USA
Posts: 406
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 A typical 'watch builder' would re-surface both the block and main-panel about .005-.010", machine for all ten dowels, add the tabs for Esprit bearings, cross-drill the crank, then line-hone so everything is 'perfect'.  The extra .030" in "line bore" cost for Chrysler bearings washes when compared to the higher cost of the Esprit bearings.

I doubt there is any significant performance difference between the Chrysler and Esprit bearings, but thinking long-term I'd want the option of multiple (low cost) suppliers the next time I did a rebuild.

If we assume a sub-200hp engine doesn't need doweling AND we assume our block isn't warped, then we could drop-in a set of Turbo Esprit bearings by machining the tabs and cross-drill the crank.  A very cost-effective solution requiring a certain amount of faith derived from looking at the old bearings. 

If we assume a sub-200hp engine doesn't need doweling, but our block is warped and our mains out of round, it would add significant cost to remove the studs, surface each side and line hone to fit those same Esprit bearings.  This envokes the dreaded While You Are At It and it makes sense to add some dowels. 

Alternatively, a line-bore for Chrysler bearings takes out a lot more material and is a short-cut around the need to remove the studs and surface each side.  It could cost a little less or may not cost any different depending upon your Machinist.

BTW:  Do be sure you are asking Mike to price the post 1986 crossed-drilled 910 version of the Esprit bearings and not the 907 version.

Last edited on 12-01-2008 12:43 am by Judson Manning