If it s hot out there 10-50, if its warm out there then 10-40, if its cold then closer to 5-40 or 5-30 or 0-30. Deppending on how cold is out there.

after every race oil and filter change period, back to oem specs. Until the new race day and before race oil change again.

Rob

 

I agree. 20W-50 all the way. That's what I used in my car with stock motor for 25+ track practice days, two seasons of autocross and 3 time attacks. When Buschur tore it down to do rods and pistons he said that the condition of the bores was probably the best he's seen given the miles on the motor (15K). I used Amsoil 20W-50 racing.

 

Mobil 1 15-50
20k miles
15k track miles
motor 100% originial to include turbo


Marty

 

Yes and yes. All the details are in the link I posted on the first page if you wanna get realllly technical with the reports.

I run in the midwest; where we'll see ambient temps of 90+ for months. This year really wasn't too bad, but there were a few days of 95+ with tons of humidity (the Autobahn RTA event comes to mind) where I even got a heatrash myself!

I seen temps peak temps on my non-TT laps of around 255 degrees. On these laps, I'd shift around 6500rpms.
On my 'hot laps' for TT/TA I'll push to 7k and near 7500rpms on a few tracks depending on the layouts of course and that really makes a difference with the oil temps. I'd see 265-270 peak - with a highest peak of the year @ 272 degrees. (I have a peak recall on all my gauges...). Taking just a 1/2 lap off would bring the temps down 10-15 degrees!

I'm not 100% sure my oil temp gauge is in the best spot. I had it installed by a local shop and I plan to have AMS double-check it this winter. It's just above the filter pointing out to the right; pretty close to the passenger side wheel. Keep in mind I run Hoosier A6/R6 and there's a lotta heat generated from there too!

 

I run Eneos 0w-50w.. on hot days like 105 degree plus,oil temp got to 270 ish..but didn't use a drop of oil the whole weekend..didn't use oil at all up to 3000miles till I changed the oil out.

 

+1
mobile1 15w50
50+ track days, 0 problems and it's only $22 for a 5 quart jug at walmart.

 

Amsoil 10w-30 Dominator on stock motor / 40 weight Dominator on my built motor

 

Best post in this thread and worthy of a massive bump-ola. I just went to walmart and bought 2 jugs of this stuff. $46 for 10 quarts. It's $7 a quart at the autoparts store. I've never seen the jug anywhere but Walmart. It even says on the bottle that you can recycle it at Walmart - so it may be specific packaging for them.

 

I personally use Motul 300V Racing Oil. Change after every track day. 600 whp+ motor never a issue and with my custom oil cooler I never see any more than 120C or 245F.

15w50 during the fall-winter then 20w60 for summer-spring

Evan Smith

 

i will go with this from this year. I had several rally friend who runs Evos and the oil as they stated is stellar.

 

^^^ Absolutely! I love this stuff, smells like candy. Being such a pure synthetic oil it needs replaced all the time. But it protects like none other and my oil temps here where temps reach 120's stay very consistent and low!


Evan Smith

 

Why has everyone moved away from the recommended 10W30?

If temps were the problem wouldn't you add additional cooling rather than change the weight?

 

My car with the built motor consumes the 10W-30, I'm hoping the 15W-50 will solve that issue.

 

15 50 mobile 1 full syntetic

 

Because I got very low oil pressure & flickering oil pressure light after lapping sessions. 10W40 fixed it.

Low oil pressure, even idling, is not a good thing.