Extreme Oil Temp in Racing Application Question

[Buckshot77]

I've been searching through the boards and basically just need a suggestion on the best starting point to finding a better oil for my car. Engine in question is a 24valve, DOHC, 3 liter duratec, custom pistons (9.5:1), running 10-12 PSI of intercooled supercharger boost at 6700-7500 RPMs for extended periods on track days.

During my first/only track outing with the vehicle in current state of tune I saw oil temps registering 285+ after 6-8 minutes of hot lapping in 80-90 degree weather. I was running a small air-oil fin type cooler that is now being replaced by a nice Mocal stacked plate unit. Oil in during the running was standard M1 0W40 with less than 100 miles on it. Water temps were about 220-230 in the car all the time. Street oil temps regularly hit about 230-235 in the car during normal driving.

In addition to switching to the Mocal oil cooler, I want to switch to a different synthetic as I've since heard bad reports on the M1 0W40. I'm planning to switch to M1 Racing 0W30, Redline Racing Oil, or RP41 oil. I think the RP is probably my first choice after reviewing the forums.

Based on the above information is a 30 weight RP41 a good place to start (possibly stay if oil temps drop to 250 or less)? Also, what interval should I send in the oil for a UOA if the engine has less than 500 miles on it?

Thanks,
Rick

 

[buster]

The RP racing is fine,as are the other oils mentioned, but I'd run Redline personally. I think it's the best oil to handle abuse IMO. Redline is dominant in road racing. Spend the extra money and monitor results with Terry Dyson. It's worth it.

 

[SSDude]

The only thing that I would like to add is that Royal Purple Racing 41 is a 40wt.

 

[Buckshot77]

I realized that after looking at their catalog. I actually just ordered a case of RP-21 to start with. I think I may have found a pretty good deal on it locally. One of our auto suppliers had it for $4.50/qt retail. Is that a decent price? I checked at NAPA and they listed it at $9.50/qt retail.

Thanks,
Rick

 

[Mitch Alsup]

quote:

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During my first/only track outing with the vehicle in current state of tune I saw oil temps registering 285+ after 6-8 minutes of hot lapping in 80-90 degree weather.

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As long as the oil stabilizes at 285dF (e.g. quits increasing) you are still bassically fine with any xW40 and some carefully selected xW30s based on HTHS numbers.

quote:

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I was running a small air-oil fin type cooler that is now being replaced by a nice Mocal stacked plate unit. Oil in during the running was standard M1 0W40 with less than 100 miles on it. Water temps were about 220-230 in the car all the time. Street oil temps regularly hit about 230-235 in the car during normal driving.

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The first thing you need to do is to measure the drop in oil temps from the new oil cooler (e.g. the change one thing at a time rule).

You could easily be in a situation where with the oil cooler, you might have needed one oil specification and with the new cooler, a different specification.

quote:

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In addition to switching to the Mocal oil cooler, I want to switch to a different synthetic as I've since heard bad reports on the M1 0W40. I'm planning to switch to M1 Racing 0W30, Redline Racing Oil, or RP41 oil. I think the RP is probably my first choice after reviewing the forums.

Based on the above information is a 30 weight RP41 a good place to start (possibly stay if oil temps drop to 250 or less)? Also, what interval should I send in the oil for a UOA if the engine has less than 500 miles on it?

Thanks,
Rick

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I have had (essentially) equal luck with M1, RedLine and AMSoil in my F355B on race tracks in both xW50 and xW40 weights (where x is 0, 5, or 10). THe xW50 stuff would temperature stabilize at 285dF, the xW40 stuff would stabilize at 260dF in 100dF days in Texas.

 

[Buckshot77]

The problem is that I never did have the oil stabilize at a given temp. I saw it hit above 290 and backed down until it would hit down to 240ish and then I'd hit it hard again for a few laps. Basically I could run 100% for about 40% of my 20 minute sessions.

Unfortunately I probably won't have the chance to switch one thing at a time as I've got an event in 2 weeks and the car is going to be getting upgraded until just before the event. Even still I was going to switch away from the 0W40 M1 in any case as I think it was to heavy for my particular engine needs.

Thanks,
Rick

 

[Terry]

Rick, whatever oil brand/wt you decide on use analysis to verify in that motor and save yourself lots of guessing and reinventing the "lube wheel" .

Terry

 

[Buckshot77]

Terry,

I had planned on getting you to do an analysis for me, but I was wondering if it would be worth it to do it with the M! I've got in there now. The engine only has 400 miles on it since the last rebuild. I ran an up to temp batch of some dino oil to get all the assembly lubes and such out, then about 200 miles of dino oil for a short break in and then switched to the M1 before hitting the first track event with the car. Current M1 has only 200 miles on it but approximately half were on an open track with peak temperatures mentioned above.

If you think it's worth it post here or drop me a PM and I'll snag a sample when I drain it this time and send it in. Otherwise, I'll just swap to the RP and send it in after the season is over. The car gets less than 3K a year put on it since it's mostly a track use car.

Thanks,
Rick

 

[Terry]

Rick, I suggest putting 2 track events regardless of time on the engine so we can see what its doing internally.

The current oil would be a baseline if you want to have that to start from. Your oil temps are high and a good lube regimen is critical to longer term operation without a failure.

This engine setup is not one that can take lots of heat unaddressed.

Appreciate the consideration.

Terry

 

[Buckshot77]

I think since I'm switching oils anyway that I'll hold off on getting the M1 analyzed as I don't think it will have much to say. I'll wait until I get a couple track events on the RP as long as I'm doing better on temps and see how that goes. According to the tech I got on my upcoming cooler I should have no problem dropping back to 250 or below as my max oil temp.

Rick

 

[Buckshot77]

I think the fuss would be that those are race specific engines and as long as they run 24 hours without dying, that's good enough. They weren't going for long term life expectancy.

Rick

 

[Eddie]

Heck: Porsche air cooled/oil cooled engines used to win 24 hour races running 320 degree F 40 wt dino oil. What's all the fuss about running Synthetic at 250-300?

 

[LarryL]

Where are you taking the oil temp?

 

[Buckshot77]

Off the back side of my remote filter setup. I don't exactly have the space to tap into my pan as the plumbing space on my car is a nightmare to say the least.

 

[LarryL]

So the oil temp you see is the temp of the oil before it gets passed to the bearings and not the temp of the oil as it leaves the bearings. In other words your engine may be running at higher temps than the gauge reading. I don't know about Royal Purple but you can call Red Line and ask Dave about your situation. You may not need to do anything, except maybe a UOA by Terry. You're on the right track, watching the oil.

 

[Buckshot77]

My new cooler should be here this week so I'm going to relocate my temp sensor to after the cooler and see what the temp going to the engine is then.

Thanks,
Rick

 

[1sttruck]

If your engine temps drop when the heater is on max with full air flow maybe more radiator will also help. Did you increase the oil capacity at all, like adding a larger oil pan or larger filter ?

The high output version of my turbo diesel uses additional oil spray on the underside of the pistons to help with cooling, and it has a 12 qt sump. The first recommendation for upgrades on my engine is to get an exhaust gas temp gauge, as you need to keep temps under something like 1300 deg or you start doing damage. It seems that a supercharger will increase temps in a similar manner, and monitorng exhaust gas temps and increasing your oil sump capacity will help.

 

[Buckshot77]

Got Plumbing? This is what I've been trying to get done on my car to help my oil temps this year (285+ on the track). I've got $500 in the cooler and plumbing but everything works as it should and driving in to work today the oil temp peaked about 185!! This along with 10 qts of RP21 (f'in $100 oil change!) and I think I've got the solution to my hot oil problems.

Enjoy,
Rick

 

[LarryL]

Rick, did you plumb your oil cooler backwards? It's hard to tell in you picture. Water radiators get hot water in the top and cool water to the pump out the bottom. Oil coolers go the other way around, hot oil in the bottom and cooler oil out the top.

 

[Buckshot77]

Larry, I'm not sure what you're asking. The oil cooler is plumbed correctly per the distributor and the inlet/outlet are both on the bottom in it's current situation. It's all controlled by an oil stat that actually determines the flow so I've got that set up correctly as well.

If you're referring to the small silver water/oil cooler it's plumbed in right as well since it's just circulating the water from the radiator around the trans fluid and the in/out flow of the trans fluid is determined by the filter path.

Thanks,
Rick