Jack Houpe
GT40s Supporter
Ok, I am going to open a can of worms. I have a question for all you that have raced your cars. What viscosity of oil are you using, at what temps and rmp is your pressure adequate?
I have been driving my 40 for almost a year and put about 4500 miles on it, all but 118 miles at normal speeds with short burst up to 100+, my oil temp have always been 200-210 even in the dead of summer. My oil pressure has always been 50-55 on cold start up then 40-45 at idle warm so I haven't been concerned as I considered this good. Last winter I changed the oil to 5-20 Mobil 1 as I didn't didn't want to put a lot of unwanted stress on the distributor drive gear when real cold engine starts. I took my car to Texas for the Big Bend Open Road Race and just left the 5-20 in the engine. Well it was 95 down there in the shade and when I ran the race for 59 miles at 4200 rpm (110-120 mph) and 59 miles back the oil temp got up to 250 which is not bad but the accusump oil pressure switch started to open and close (pulsate) during the run. I have a light on the dash that tells me when its below 35 psi and accusump is open. I have a high volume high pressure pump. My question is what is low pressure at rpm, what viscosity oil should I have used? When the idiot light started to blink the idiot got nervous. I have a Dart aluminum 351W block bored to 427. Using the standard oil cooler provided by SPF. Engine holds 8 quarts and accusump another 3.
I have been driving my 40 for almost a year and put about 4500 miles on it, all but 118 miles at normal speeds with short burst up to 100+, my oil temp have always been 200-210 even in the dead of summer. My oil pressure has always been 50-55 on cold start up then 40-45 at idle warm so I haven't been concerned as I considered this good. Last winter I changed the oil to 5-20 Mobil 1 as I didn't didn't want to put a lot of unwanted stress on the distributor drive gear when real cold engine starts. I took my car to Texas for the Big Bend Open Road Race and just left the 5-20 in the engine. Well it was 95 down there in the shade and when I ran the race for 59 miles at 4200 rpm (110-120 mph) and 59 miles back the oil temp got up to 250 which is not bad but the accusump oil pressure switch started to open and close (pulsate) during the run. I have a light on the dash that tells me when its below 35 psi and accusump is open. I have a high volume high pressure pump. My question is what is low pressure at rpm, what viscosity oil should I have used? When the idiot light started to blink the idiot got nervous. I have a Dart aluminum 351W block bored to 427. Using the standard oil cooler provided by SPF. Engine holds 8 quarts and accusump another 3.