Honed???
I’m guessing you mean the cylinder bores. Honing is an operation that puts a finish and final clearance on the cylinder walls after boring to a standard oversized, not an operation that resizes the cylinder wall. So this leads to the question of what exactly has been done.
Getting into the zone of 500-550 hp requires everything be just right. This range is pretty much at the strength limit of a stock block got the old iron SBC.
With power enhancers like turbo’s or laughing gas usually the first things to fail are the pistons. Here the fit of skirts to wall and rings to their lands is a critical necessity. Pistons need to be forging that have resistance to structural loads both operational and from detonation. The latter is the big killer of pistons, rods and crank. The heat and forces melt the sides out of pistons or just outright busts them. The forces down the rod usually blows the oil out of the clearance quickly followed by the bearing shell welding to the crank journal, then welding to the rod followed by the rod busting. The crank is usually the last to surrender with a fatigue failure in the cheek area, although oil starvation on the mains for a list of reasons can be its demise. The big issue with a cast crank is pounding the rod journals out of round which opens up the oil clearance which then goes down the path previously described.
From what little I can glean from your description it seems too much effort is going into turbos and too little into the basic engine.
Bogie
