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Pressure (PSI) is an indication of resistance, not flow.I don't know if anyone is still reading this post, but since I'm a Newbee and have only gotten so far in my reading I'm really behind the eight ball here.
As a ASE certified Master Mechanic for over 30 yrs I've seen a lot of engines blown apart. The main reason I've seen pistons ventilate blocks is due to
lack of oil. Most all diesels and heavy gas engines ( IHC etc.) have large surface areas on the rod bearings and when these engines start spinning high
they really need the lube to keep the clearances up. Remember, the bearing really rides on a film of oil not the bearing itself. When you spin high with a low volume
oil pump and low pressure like the multifuels (30 psi ) the system cannot keep up with the oil lose, this creates heat, which creates friction , which creates added stress to the rod bolts,
which ends up with rods flying through block ! That is why all racers use high pressure, high volume oil systems costing lots of money !
I've built up International engines that can really rev , but you need high tensile strength bolts, balanced rotating mass, and really good lube systems. Not to mention
high pressure valve springs and lifters and cams !
Have you had a multifuel open before? There's two oil filters, huge pick ups (two), also they run 30psi at idle. Hot and at speed is typically 60psi. Also there's oil squirters for the pistons. I'd have to say these are not low volume setups.
The rod bolts tend to be a common theme to this discussion. There's a number of reasons they're discussed. But I personally would side more towards the fact that these engines (in their original diesel only config in tractors) had a much lower operating range. They were then asked to increase that range, increase the CR substantially, and then you also have to consider that most of the engines were "rebuilt". Often, the rebuilders had only picked up a wrench recently.
I'll see if I can find my scale, but I've got a set of take out rods and pistons from a MF. I'd be willing to bet there's a good bit of difference between them.
This is absolutely my opinion, but I believe a LDT/LDS could be rebuilt to balanced and blueprinted spec. A better set of rod bolts installed. And you could subject them to 3K rpm all day long. I do not however think I'd replace the valve springs, as the actual camshafts have been known to shear at the sprockets. (I would however check and shim all the springs to ensure even valve seat pressures)