That's a great article, but it STILL misses the point. I made I've 2 HP/CID at 8500 plus RPM and never, ever failed a main bearing because I had a groove in the lower. Ever.
The biggest issue is getting oil to the rods full time causes excess oil on the cylinder walls and extra oil in the crank case to wrap around the crank and suck HP and fuel mileage.
That's why I always use a windage tray and a QUALITY crank scraper that scrapes on the up and the downside.
Still, if you can run a half groove bearing and not have the rods jailbreaking off the crank is obviously the best option.
As was pointed out on ST several times, not every guy out there has an ASScar engine shop in their backyard and full time team of hydraulics engineers on staff to tackle every single issue.
As was also pointed out on ST was the oil timing issue, and just like when I bring it up on here, the same people over there poo-poo it.
It's a real thing, a real issue. And it matters.
I forgot to mention the other issue with full groove mains is you MUST use a HV and high pressure pump. Another thing that can eat some power and rob some fuel mileage.
Of course, when you have rod bearings rubbing on the crank, HP goes down rather quickly and the drops off exponentially as each rod leaves the crank and puts a hole in the block and pan, smacks the cam and bends the hell out of it and if you are not lucky (I'm not) that rod will swing around and catch a lobe and lifter just right, and then the lifter ***** it's needles all over the place.
BTDT.
You can NEVER have a common sense discussion about oil timing and bearing grooves if you never admit the oil timing issue and how to fix it. And even then you need to do things you'd never do...like cross drill the crank and still use full groove mains.
All the tubes and hoses and tricks and blah blah blah don't do a thing to fix oil timing. And none of them work.
A good liking system for big HP and RPM requires a minimum (a bare assed minimum) of a 1 inch pickup and a dual pick up is even better.
A QUALITY rear sump pan. Good luck finding that today.
A HV/HP pump.
Full groove mains.
Oil timing corrected.
You do that, and get everything else correct like the best rocker/pushrod geometry you can get and you can easily, EASILY make 2 HP/CID at 8000 plus RPM all day long and never hurt a bearing.
