Larry, the photos of the windowed block you posted (2nd and 3rd photos in your first post) were of the 350 to 455 pit swap in 2004 Salem as it was getting yanked out.
So are there really zero documented bottom end block failures for a properly tuned, properly assembled, normally aspirated big block Buick except those that can be traced to a broken rod, broken crank or other contributing cause?
Nitrous, and forced induction are the major contributors. After that, lack of oiling, detonation or too much RPM.
Everyone would likely agree with that statement, regardless of engine nameplate. So does anyone have information about a broken or cracked bottom end in a big block Buick that was normally aspirated, and didn't break a connecting rod or crankshaft first? Hugger's original post is an interesting question and I expected to see a dozen examples posted right away.
Cylinder walls are thin and when block moves around walls can develop cracks. The more hp, the more rpm....contributes to likelihood of it happening. 400 has most meat so best choice for boosted applications IMO.
Denny Manner once told me it isn't the HP as much as it is the RPM. Lighter pistons and rods help a lot.
Hugger asked in the first post: "want to see your block failure pics!!!,...come on with so many people believing our blocks are garbage and self destruct when you hit "600" hp,..prove it,..i want to see these busted mains,...that were in well tuned and cared for combos,...for every 1 posted I'll post 5 that are are alive and well with stock blocks over 600hp,..aaaannnndddd GO!!!" So has anyone had the misfortune of busted mains in their big block Buick that was normally aspirated, and didn't break a connecting rod or crankshaft first? Or is a broken block actually very rare because a crank or rod breaks first? I'm curious because I've been spinning my 13:1 stock block 462 to the 6,800 rev limiter for many years and everyone tells me "you will break the block in that thing" but it looks like I'm actaully more likely to break a rod or crank than breaking the block. Is that correct?
My thought is with the thin block and thin main webs you get flex which reduces or caused 0 clearance in the bearing area......so you damage the bearing which leads to damage cranks then your boom..... you would be able to full trace back.....you would find the bad bearing and blame the oil flow. Put a magnetic dial indicator on the out side of the block, spin the motor and you can on some block see it move.
Chris Skaling posted the following: This was not caused by detonation in my eyes, there was no sign of that on the pistons, rings or back of bearings. The timing was NEVER more than 32*-34*. My thought is, if you hang a bunch of weight off both ends of the crank and there only supported on one side of the weight to boot, add 625-650 hp, 10 plus years of being beat'n like a red headed step child to a wimpy block something has to give. Just my thoughts. All the main caps have been walking & talking big time. I thought maybe if the weight was more to the center of the crank (internal balanced) it would be way easier on the blocko No:Chris
my whole point of this was to maybe give guys the courage to build tge 600,..650,...700hp 455 they have been dreaming about without believing they NEED or MUST have a girdle when they aren't going to bracket racing it When they aren't going to be putting it in a 5klb barge When they aren't going to be running standing mile races When they aren't going to trying to make a 1khp Etc etc,.. My brothers new engine should hit 725hp with the new SPX and Dominator,....im not concerned one bit about it to be honest,..because ill run it a few times a year at most,..im capable of keeping the tune safe and I know how not to abuse stuff,.. Build away fellas,...i am,..
our pistons are lighter than ever,..bearing technology has come a long way,.. we now have dedicated buick offset rods,..etc,..its not 1994
