after searching for a good high mileage oil ive decided to go with mobil 1 hm 10w30 for my 94 lt1 with 192k on it. The car is only driven during track season march to november. Car maybe sees 300 miles a month, with about 20 track passes a month. Car is a stock internal bolt on car that runs 12.7's. It has a small oil leak (1 to maybe 2 quarts of oil a month) it consumes no oil. Ive decided to use a hm oil to slow down the oil leak unti i have enough money to build the motor. Ive decided mobil 1 hm because i can only find two fully synthetic hm oils valvoline and mobil 1. Mobil 10w30 hm has more visocisty then valvoline for a 30 weight. I plan to stick with a 30 weight due to the motor having stock clearances. What kind of oci inverval should i do with this vehicle?