OMG Hillbilly Engineering! Just ran across an ad for a "427", doesn't look too bad until I came across this in the description- "The block never came with cross bolts mains so I put bolts in". Huh? So I search thru the pics, and it's obviously a marine block with the big cut through the oil gallery, and then the pic of the "bolts". Look carefully, looks like some "bolts" just screwed up against the sides of some stock main caps- there are no bolt bosses on those caps...
Not too crazy, there is a technique done on cylinders called "posting" that does similar. The import guys do it all the time. If Holman-Moody would have come up with this it would be followed like one of the ten commandments. Thankfully Ford made the side bolt caps
How the heck does one install the bolts and feel comfortable that they've put the correct amount of pressure against the side of the caps, and not caused more harm than good?
Some really high end Super Stock (or just big) 427s get similar stuff done, but vertically to support the decks- boring thru the cylinders, install rods and then flanged cylinders. Kinda expensive
I got a buddy in Kansas that has a '65 427 medium rise post car (bought it new). he has tons of 427 parts other then blocks. Just for chits n giggles he JB welded some bolt heads onto a 428, and tells everyone that it is one of half a dozen 428 side oilers. It just sits on an engine stand in his shed.
Back in the 80s I had a friend who raced 427 Ford Fairlanes, I won't mention his name. One day I stopped by his garage and he showed me a 390 that he installed 427 crossbolt mains on. I asked him how he drilled the block and he actually told me he used a hand drill. I moved to another town soon after that so I don't know how his engine ran.
It used to get done a lot back when you could still get new blocks, if one got grenaded pretty good the caps would get saved when the block was tossed, used to be able to buy sets of crossbolt caps at the swaps for $50- price has gone up considerably, when you can find some- I only have one extra set right now. I wouldn't try the hand drill route, but the spot facing "should" be done square with the crank/caps, and if it's set up on the mill to spot face, the drilling could be done at the same time. Makes me wonder how he did the spot facing to get it square? There were a lot of "unconventional" thinkers playing with these engines from the 60's on, Carl Holbrook, "Crazy Nate" Cohen, and Ray Paquet, who is well into his 70's and still "The Man" rowing the 4spd in his Thunderbolt, 29 Indy Nationals wins. Holbrook's son Chris is still in business, and built a 440 ci 351W for my buddy's 66 Fairlane, single 4V on gas, 1065hp, runs 9 flat