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Old 01-23-2007, 02:55 AM
Jack Gifford's Avatar
Jack Gifford Jack Gifford is offline
formerly 'Pontiac Jack'
 
Join Date: Dec 2004
Location: Phelps, NY 14532
Posts: 10,340
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First an attempt at a direct answer for your case- with the availability of 3/4 groove main bearings, most Pontiacs are better off without the cross-drillings- assuming no aluminum rods and engine speeds in the range of 7,000 RPM and below.

The more-generalized answer is more complex, and must take into account many other engine details. For example, my blown-alky Pontiacs needed the mains cross-drilled as part of the overall scheme, to let them live at up to 9.000 RPM for many seasons. The David Reher quote makes some important points, but is somewhat flawed. The most glaring flaw is to compare his experience with a 'high-speed-drilled' crank versus a cross-drilled (non 'high-speed-drilled') crank. And for whatever it's worth, I doubt that many of us could consider the 'high-speed-drilling' of a Pontiac crank.