I almost hate to be posting one of these threads, but what the heck.
I recently bought a '92 NSX. It's a lot of fun on the track. I'm currently running M1 0W-40 in it as I've run that in every other track car I've owned (and most non-track cars, too) and it's "just worked". This weekend I was seeing oil temperatures climb to about 275F. Oil pressure was fine, even at idle.
There's a lot of discussion online about oil temperatures, specifically how hot is too hot, but nothing consistent or concrete. I decided to contact Mobil 1 and see what they thought. This is their answer:
=====
Good question Robert, but you are still in good shape at 275⁰F. I can tell you that Mobil 1 will resist breakdown and the formation of sludge/varnish up to 500⁰F. Realize that is simply from an oil integrity perspective – the viscosity will be that much thinner (possibly too thin for optimal lubrication), and oil life is compromised. Since the 0W-40 you are running is thicker than the OEM recommends, you are already mitigating some of that risk.
If your personality is anything like mine, I would not want to see oil temperature right on the limit, but instead I’d leave a good buffer. I would set 300⁰F as a conservative limit. I’m no expert on these vehicles, but I would think that if you can’t run wide open under 300⁰F, it might be a sign that extra cooling (oil or water) is required.
=====
I have been mulling over the idea of moving to Red Line 10W-30 or possibly 5W-40. I'd love to hear folks' thoughts on oil temperature and the idea of changing oils.
robert
I recently bought a '92 NSX. It's a lot of fun on the track. I'm currently running M1 0W-40 in it as I've run that in every other track car I've owned (and most non-track cars, too) and it's "just worked". This weekend I was seeing oil temperatures climb to about 275F. Oil pressure was fine, even at idle.
There's a lot of discussion online about oil temperatures, specifically how hot is too hot, but nothing consistent or concrete. I decided to contact Mobil 1 and see what they thought. This is their answer:
=====
Good question Robert, but you are still in good shape at 275⁰F. I can tell you that Mobil 1 will resist breakdown and the formation of sludge/varnish up to 500⁰F. Realize that is simply from an oil integrity perspective – the viscosity will be that much thinner (possibly too thin for optimal lubrication), and oil life is compromised. Since the 0W-40 you are running is thicker than the OEM recommends, you are already mitigating some of that risk.
If your personality is anything like mine, I would not want to see oil temperature right on the limit, but instead I’d leave a good buffer. I would set 300⁰F as a conservative limit. I’m no expert on these vehicles, but I would think that if you can’t run wide open under 300⁰F, it might be a sign that extra cooling (oil or water) is required.
=====
I have been mulling over the idea of moving to Red Line 10W-30 or possibly 5W-40. I'd love to hear folks' thoughts on oil temperature and the idea of changing oils.
robert