[G.R.]

Ernie best check your Ford history---the 427's S/O's(Nascar btw) usually grenaded themselves "Back in the Day"even in 200-500mi races(Nascar). That they managed to keep them together for 24hrs was indeed a feat of engineering.
BTW--From the factory all race teams tore them down and rebuilt them before they raced them, the teams didn't use them out of the box if they wanted to win.
Think I'm wrong, then why did the very first 427(a Nascar crate engine) put into and raced in a Cobra grenade after a very short time? The next engine the Shelby team rebuilt before it was ever installed.

They were not all that dependable, maybe on the street but not the race track. I'll grant the 7litre was in the Lemans GT-40 wins but I'll bet you dollars to donuts those were not "box stock".
Not trying to start anything