Magnum vs LA block...differences...preferences

cpearce said

Is there a guide, or information somewhere on how to drill Magnum blocks for LA oiling? Although I have NO experience with Magnum blocks, I recall hearing about better machining tolerances and less core shift in them and the roller LA blocks vs. the older LA blocks.

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Pretty sure it's just a straight hole from the top of the deck down to the cam bearing but that's about 5" of cast iron to drill through and it needs to be precise to get it to end up in the right place. You can easily see on an LA block where the passage starts and ends and even the casting "bulge" for it, Magnums retained that just skipped the drilling. A machine shop could probably do it but for mine I just went the external oiling route like shown above.

One of the holes in the sides of most LA cylinder heads (at least my Edelbrocks) for bolting up accessories just happens to line up perfectly with the rocker shaft stands... drill that through, re-tap the threads for NPT and you've got oil. For any realistic power level in a street-strip car I'd personally just get a pair of EQ heads and use the Magnum-style rockers, stock or aftermarket.