Well I scored an R3 Magnum race block last week, it is a virgin untouched block that I will be transferring all my parts over into from my stock block 410 engine.
I was going to find the limits of the stock block for the hell of it, so far the stock block has held 1000hp at the crank. Now that I have found a unicorn I'm not going to test the stock block limits and possible destruction of my internals and possibly my heads.
For now it will be a 410cui engine, later on I will build a 426 (4.125 bore 4" stroke) turbo engine with maybe Victor heads.
Look for some very low numbers soon as I will no be able to use all of my sledgehammer plate without fear of splitting the block.
Specs on the block (when they were still made)
https://www.jegs.com/webapp/wcs/stor...&storeId=10001