I personally inspected parts from this engine, and this failure is not due to 4-bolting a passenger car block.
Bull Crap??? LOL here is your picture.
This image first appeared on another engine forum in a thread in support of the OP's general statement that OEM passenger car blocks cannot hold big horsepower, and he supported his claim with several images of carnage including this one. The images are so "over-the-top impressive" that the thread went viral, so to speak, and everyone went ga-ga over them and no-one questioned the claims.
However, upon actual inspecton of the engine it was discovered that when this engine was built, parts were put in BACKWARDS by the engine builder which made for all kinds of problems including an interference fit, and so the crankshaft was effectively being hammered against of the lower end and main caps....which ultimately took out the main webbing. That's what really
caused this block failure, not a measely 850 hp (or whatever it was) on a typical 4-bolt conversion.
As someone who campaigns the use of OEM passenger car blocks in high performance builds, I have always been offended by this image being mistakenly utilized, and not only used out of context but also stated as fact when it is absolutely not true in any way whatsoever
. And it further disgusts me that the OP never "manned up" and admitted he screwed up after he was told of the horrid oversights in his build.
This wasn't the blocks fault at all, nor was it due to a the modifications done to the block. Claiming otherwise is either misinformation or a downright lie (depending on who is saying it).
P.S.: My biz partner, Billy, ran >90+% nitromethane through an unfilled D1VE std-web block with a 4-bolt conversion, generating thousands
of horsepower, and did so down a 1-1/3 mile track for 7 years with zero problems. And while a feat unto itself it is nevertheless 100% fact.
P.P.S.: Don't drag me into this thread, Steve, I'm only straightening out the truth about the image posted and nothing more. The claim behind the pic is bogus. I still have pictures of the culprit parts from this engine.