Absolutely. New engine program will run a break-in session and pull the bottom end and mic the bearings and look at scuff patterns. If they are all OK, we have the right oil. We never put a motor out with 5W-30.
!0W-30 or maybe 10W-40 for a street engine. More likely 15W-40. But the oil is often a cam grinders choice and we have to use their guidelines or no warranty. I know it sounds crazy, but say Howard's Racing Cams is the supplier, they have a full 5-year warranty on a complete valve train package. I won't jeopardize that by6 going off spec. They spec Brad-Penn 10W-30 (or equal) for break-in. I have permission to use VR-1 (silver bottle) as an equal.
Nitro motors do not break valve trains the same way. They lift heads and induce carnage, or hole a piston (lean) fry the bottom end. For those case we are not looking at warranty. We are looking at survivability...
I no longer care to chase the brass ring and try to build absolute class winners. Those guys are a parts vacuum machines as the breakage rates are so high. Yeah, they can be looking for 1~2 HP and anything that will get there including running tighter clearances (0.0015~0020 for 5W-20 equivalent race oils) on the big ends to reduce viscose drag. But, see where that gets them? No give at all. One surface not polished and round enough will spin a bearing and toss and engine in nothing flat.
If I tried to build such an engine, I'd be looking at 75 PSI hot for 20 grade at OP temp to try to make sure I was oiling well enough... And now I just gave up the gains to pumping losses...
!0W-30 or maybe 10W-40 for a street engine. More likely 15W-40. But the oil is often a cam grinders choice and we have to use their guidelines or no warranty. I know it sounds crazy, but say Howard's Racing Cams is the supplier, they have a full 5-year warranty on a complete valve train package. I won't jeopardize that by6 going off spec. They spec Brad-Penn 10W-30 (or equal) for break-in. I have permission to use VR-1 (silver bottle) as an equal.
Nitro motors do not break valve trains the same way. They lift heads and induce carnage, or hole a piston (lean) fry the bottom end. For those case we are not looking at warranty. We are looking at survivability...
I no longer care to chase the brass ring and try to build absolute class winners. Those guys are a parts vacuum machines as the breakage rates are so high. Yeah, they can be looking for 1~2 HP and anything that will get there including running tighter clearances (0.0015~0020 for 5W-20 equivalent race oils) on the big ends to reduce viscose drag. But, see where that gets them? No give at all. One surface not polished and round enough will spin a bearing and toss and engine in nothing flat.
If I tried to build such an engine, I'd be looking at 75 PSI hot for 20 grade at OP temp to try to make sure I was oiling well enough... And now I just gave up the gains to pumping losses...