IN a pro charged drag race engine with a dry sump oil system, what weight oil should be used in an 1800 hp or so engine? Being as the dry sump system keeps the oil cooler and if your sitting for a while on the ropes of a drag boat race, your oil is steadily cooling off and the oil pressure is a lot higher the cooler the oil is. This is with using a 20-50 oil. should the higher viscocity oil be used for the shear strength of the thicker oil with a boosted engine or should a lower viscocity be used to keep the oil pressure in reasonable range? Is it true the thicker oil provides better safety margin with boosted engines for a short drag race. Its just hard to keep any oil temp in a motor waiting for a run.