BruceH
BBB Big Bore Boss 322
How long do you think it will be until you spin a bearing or the top end goes from lack of lubrication? AFAIK using the recommended weight has resulted in zero issues.
How much oil does a 5.0 4v need flowing through the bearings to maintain a wedge? Which viscosity allows for a wedge to form while still moving enough oil to prevent heat build up? How about the amount and pressure to make it to the top and maintain a wedge for the cams and lubricate the valve train?
Knowing that information then I'd ask what oils will maintain the flow and psi needed to protect the motor? Of course we will use the stock oil pump for the baseline.
How does all of that change with 10w-30? Other than being thicker at start up which affects the quality of the wedge in a negative way what do you get from it? Do you have a motor with increased clearances that needs a thicker oil on start up?
How much oil does a 5.0 4v need flowing through the bearings to maintain a wedge? Which viscosity allows for a wedge to form while still moving enough oil to prevent heat build up? How about the amount and pressure to make it to the top and maintain a wedge for the cams and lubricate the valve train?
Knowing that information then I'd ask what oils will maintain the flow and psi needed to protect the motor? Of course we will use the stock oil pump for the baseline.
How does all of that change with 10w-30? Other than being thicker at start up which affects the quality of the wedge in a negative way what do you get from it? Do you have a motor with increased clearances that needs a thicker oil on start up?
I run 10w-30 as well. Car is only driven in the Spring/Summer months though.
Ford Motorcraft 5w-20 is actually closer to 5w-30 and their 5w-50 shears down to a 40 weight in under 1000 miles.