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Do not track my car and while oil temperature gets "high" (230F) in some cases -- in town driving -- I'm not that concerned by 230F oil temperature and do not feel the need to add an oil cooler.

But for those that track the car certainly one of the oil coolers pictured deserves some consideration.
 

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Also, I note I used water/oil cooler referencing my Hellcat. I was thinking of my Porsche cars which all had a water/oil cooler fitted from the factory. The Hellcat oil cooler is an air/oil cooler. Sorry for any confusion.
 

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Discussion Starter #23
The only thing confusing me is how hot is too hot on the track. Obviously we can't have it stay the same as it would be just driving normally on the highway. That would probably be ideal, but not realistic. In order for oil cooling to work that good in severe use, your oil would probably never get warm enough during day to day trips.

So for what's acceptable on the track without engine damage, there seems to be some discrepancy from different members here. Some say synthetic oil can handle 300 F, some say anything above 212 is too high, and anything in between. I honestly have no idea one way or the other.

I don't want to spend a bunch of money on an aftermarket cooler, that may or may not fit right, could possibly leak, or have to remove in winter, etc. if it turns out that the temps I'm seeing are ok once in a while.

So my next thing to try will be simply remove the grille opening or belly pan and see what happens.
 

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Unfortunately the Hellcat oil cooler won't simply add on to a 392 car. Aside from eliminating the coolant passages from the thermostat housing and the lower rad hose, the hellcat cooler doesn't fit behind the fascia according to Steve White parts. The foglight takes that space also.

If you have a 2019 392 widebody, it would probably be a much easier upgrade to add.
no room on the passenger side due to the power steering pump assembly, and depends on the year and model, also, pretty sure will not fit standard fascia, not enough space, we tried on Bigred's original nose
 

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The only thing confusing me is how hot is too hot on the track. Obviously we can't have it stay the same as it would be just driving normally on the highway. That would probably be ideal, but not realistic. In order for oil cooling to work that good in severe use, your oil would probably never get warm enough during day to day trips.

So for what's acceptable on the track without engine damage, there seems to be some discrepancy from different members here. Some say synthetic oil can handle 300 F, some say anything above 212 is too high, and anything in between. I honestly have no idea one way or the other.

I don't want to spend a bunch of money on an aftermarket cooler, that may or may not fit right, could possibly leak, or have to remove in winter, etc. if it turns out that the temps I'm seeing are ok once in a while.

So my next thing to try will be simply remove the grille opening or belly pan and see what happens.
All i have to go on regarding oil temperature comes form The Porsche 911 Performance Handbook by Bruce Anderson.

Anderson spent a considerable portion of his life trying to obtain more power, reliable power, from mainly the air-cooled Porsche engines which are really oil and air cooled. 'course, the oil is cooled by air eventually. Our "water cooled" engines are also really water and oil cooled. (And to state the obvious both the water and oil are air cooled eventually.) A good example oil cooling is the piston oil jets the oil they supply can lower the piston operating temperature by 50C. The engine oil is in contact with the hottest parts of the engine: The pistons -- via the oil sprayed to the underside of the piston crown -- and the exhaust valve stems.

Anyhow, Anderson writes the operating engine's oil temperature wants to be around 200F. This is in the "middle" of what he says is a proper a temperature range of 180F to 220F.

Anderson goes on to write: "An oil temperature of 230F is warm, 240F is hot, and 250F is to damn hot. I wouldn't worry too much about seeing either hot [240F] or too damn hot [250F] on a trip. It would be on an everyday driving basis or with a dedicated track car those temperatures would concern me."

As I have mentioned my Hellcat's oil temperature can reach 230F when I subject the car to "considerable" town driving. Just law abiding normal town driving. This doesn't concern me in the least. And in fact I "welcome" it as with the elevated oil temperature and the "hot" engine water vapor remains vapor and is carried out of the oil and crankcase and this helps to keep the water content of the oil down.

I haven't had my Hellcat out on extended road trips like have done with my other cars but based on my short freeway/highway excursions -- 60 miles or so -- oil temperature appears to be well under control. The oil temperature tends to settle in to a bit under 200F. On milder days a bit lower still closer to that 180F temperature mentioned above. I have not yet encountered any real long steep grades, such as the grade on 58 highway east of Bakersfield CA that runs up to Tehachapi (or the grade coming from the west the grade that starts just outside Mojave and on up to Tehachapi and there are of course countless others that I have have encountered on my road trips back and forth and up and down the western USA) but I believe the oil temperature will not be affected that much. The engine doesn't work that much harder. Say 50hp is sufficient to move the car down a level freeway at 65mph. It will not take anywhere near the engine's maximum output to climb the steepest grade.

Unlike on the track where the engine is called upon to deliver max or near max power over and over again with just short breaks between these.

So were I to track my Hellcat I'd seek some dependable way of keeping the oil temperature within that 180F to 220F range.
 

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FWIW, I was stuck in horrible traffic leaving Pittsburgh yesterday afternoon, it was about 89° out. Idling in traffic, then through long tunnel with more heat buildup, probably 120°ish by the end, oil temp was about 235° once I got moving, it creeped down about a degree a minute to the high 2-teens.
 

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FWIW, I was stuck in horrible traffic leaving Pittsburgh yesterday afternoon, it was about 89° out. Idling in traffic, then through long tunnel with more heat buildup, probably 120°ish by the end, oil temp was about 235° once I got moving, it creeped down about a degree a minute to the high 2-teens.
Does not surprise me. I would expect, well, would not be surprised, if I elected to drive my Hellcat on hotter days in the middle of hottest part of the day under similar driving conditions the oil temperature would climb to beyond 230F.

While I often drive my Hellcat on hot days -- a while back daytime highs were in the triple digits and the next few days highs are expected to be in the mid 90Fs -- it is believe it or not rare that I drive it in the hottest part of the day. M-F I'm at the office and my office is located near the east shore of the SF Bay and while inland it can be 100F where I am it is 20F cooler. And often during the day at the office I don't even use my car after arriving at the office until it is time to leave in the evening. In the evening then while I am driving back to where the temperature was hot during the middle of day at the time I drive the temperature has fallen and is under 90F often times even cooler.

If the hot temperature arrives on a weekend as is my habit I do any running around early in the AM -- finishing up no later than 10am -- then I am home the rest of the day only venturing out around noon to eat. And for running around town I generally leave the Hellcat parked and take the Mini JCW which is a much nicer car to use for in town errand running.

As has been the case with my other cars I expect so too will it be the case with my Hellcat. I'll encounter high ambient temperatures and spend some time driving in them while on an extended road trip. In the past I've encountered 100F+ (up to 116F even once 119F) ambient temperatures and spent hours driving at some speed in these high temperatures. None of my cars manifested any signs of being affected by the heat. In the case of the 119F I was in my Turbo. The A/C was set to 72F and the cabin temperature was comfortable and the A/C was not even working hard. (The Turbo, and the Boxster, both had excellent auto climate control systems.) It was only when I happened to glance down specifically to look at the outside temperature I noticed it was 119F. Because there was no sign from the car it was operating in this "extreme" heat I sort of questioned the temperature display and I touched the side glass and sure enough it was "hot".
 

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Hey all, haven’t been posting much here lately. This thread popped up in the periodic summary email the board sends out, so I thought I’d chime in, as the subject has come up on an oil forum frequently. Bottom line: don’t worry unless oil temp gets close to 300 for extended periods.

More detail: modern engines deliberately run the oil pretty hot. On the Hemi and Pentastar, the oil cooler (when equipped) actually heats the oil if the oil temp goes below coolant temp (most of the time in casual driving). Some Pentastar documentation I’ve seen claims that 190F is considered the minimum desirable oil temp. My 12 SRT8 seems to run a minimum of 215, even in freezing weather (eventually- takes a while to get there). One reason is that oil temps over 210F drive out moisture that can form acids with other combustion blow-by products, like sulfur traces in the gasoline. Even Co2 and water creates a mild acid, after all. Another reason is that iron-on-iron rubbing contact (rings against cylinders) has a wear minimum that happens somewhere between 220 and 250F. It’s not super significant (meaning running the oil at 190 isn’t going to make the engine have a noticeably short life), but it’s been verified. Third, modern oils don’t degrade in heat nearly as bad as 30 years ago. A member of another forum I’m on used to track a 6.1 SRT at Maimi Homestead’s infield course, and would see 270-280 temps. He contacted Mobil and asked about m1 0w40, and was told “it’s fine anywhere below 300F, no need to change it soon or anything.” I have no doubt the same is true for Pennzoil Platinum, Redline, Amsoil Signature, etc.

Another piece of trivia: WAY more heat in the oil than you think (during non-track driving, anyway) comes not from cooling the undersides of pistons, but from the friction of the oil itself being sheared inside the bearing clearances. Those with a manual car can try this next time you’re on a long, flat drive. Hold a constant speed in 6th and watch the oil temp until it stabilizes. Then drop to 5th, hold the same speed and watch it climb about 5-10 degrees over 10 minutes or so. Shift back to 6th and it’ll slowly fall back down. The engine output power is the same since air resistance is the same if you hold a constant speed, so the temp increase mostly has to come from friction.
 

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Hey all, haven’t been posting much here lately. This thread popped up in the periodic summary email the board sends out, so I thought I’d chime in, as the subject has come up on an oil forum frequently. Bottom line: don’t worry unless oil temp gets close to 300 for extended periods.

More detail: modern engines deliberately run the oil pretty hot. On the Hemi and Pentastar, the oil cooler (when equipped) actually heats the oil if the oil temp goes below coolant temp (most of the time in casual driving). Some Pentastar documentation I’ve seen claims that 190F is considered the minimum desirable oil temp. My 12 SRT8 seems to run a minimum of 215, even in freezing weather (eventually- takes a while to get there). One reason is that oil temps over 210F drive out moisture that can form acids with other combustion blow-by products, like sulfur traces in the gasoline. Even Co2 and water creates a mild acid, after all. Another reason is that iron-on-iron rubbing contact (rings against cylinders) has a wear minimum that happens somewhere between 220 and 250F. It’s not super significant (meaning running the oil at 190 isn’t going to make the engine have a noticeably short life), but it’s been verified. Third, modern oils don’t degrade in heat nearly as bad as 30 years ago. A member of another forum I’m on used to track a 6.1 SRT at Maimi Homestead’s infield course, and would see 270-280 temps. He contacted Mobil and asked about m1 0w40, and was told “it’s fine anywhere below 300F, no need to change it soon or anything.” I have no doubt the same is true for Pennzoil Platinum, Redline, Amsoil Signature, etc.

Another piece of trivia: WAY more heat in the oil than you think (during non-track driving, anyway) comes not from cooling the undersides of pistons, but from the friction of the oil itself being sheared inside the bearing clearances. Those with a manual car can try this next time you’re on a long, flat drive. Hold a constant speed in 6th and watch the oil temp until it stabilizes. Then drop to 5th, hold the same speed and watch it climb about 5-10 degrees over 10 minutes or so. Shift back to 6th and it’ll slowly fall back down. The engine output power is the same since air resistance is the same if you hold a constant speed, so the temp increase mostly has to come from friction.
"Hot" oil is not necessarily bad. Really I don't consider 212F oil "hot" just at its working temperature. And even hotter. I've seen my Hellcat engine's oil temperature reach 230F in sustained town driving. This 230F hot oil doesn't bother me. As a matter of fact I kind of like to see the oil get this hot as I pretty much assume this boils out any accumulated water.

(My first time with a Macan diesel loaner I watched the oil temperature climb way above 212F to 240F and higher. So high and at the time seemingly too high I stopped in at the dealer to ask about this and was told it was "normal" the way the automaker (Porsche) intended.)

As you touched upon "hot" oil -- 212F or hotter (ignoring the boiling point of water in the hot oil can be less than 212F due to the fact the crankcase often operates at less than atmospheric pressure) helps remove water and water is a critical component of acidic compounds that form in oil as it accumulates miles and contamination.

A benefit of the hotter oil is it it gets the surfaces that the water vapor comes into contact with up to 212F or higher so the water vapor does not turn back into liquid water and reenter the oil. The water vapor remains water vapor until it is removed via the crankcase ventilation system.

Regarding what the Mobil supposedly said... Really I have to question just picking up the phone and calling Mobil and getting someone who is a real authority on oil and picking his brain... I mean I've worked for various companies and have been on occasion on some subjects the "real authority" and even if someone contacted me -- which is not easy as I seldom use my office phone and don't give the number out (I don't even have a business card) -- I would just refer him to the company's published literature for the specs, operating conditions, etc.

Anyhow, my recommendation is I would want to avoid running the oil at 300F even if the oil (supposedly) can take it. For one thing while I would show up at the track with fresh engine oil not everyone will. Fresh oil may well withstand prolonged operation at elevated temperatures while "old" oil may not.

While engines are very similar there can be differences and one engine's oil budget differs from another engine's oil budget. Thus one engine is quite "happy" with ~300F oil while another engine may have slightly tighter clearances which as you touched upon can result in higher levels of friction and thus raise the oil temperature in the bearing to the point the oil breaks down.

As you noted, a goodly amount of heat comes from oil friction. Allow me an aside: Some couple of years ago in discussing oil for a guy's engine it came up he was using 15w-50 oil which while favored by some owners was not recognized as an oil suitable for his engine. I advised him to use the right oil, in this case a 0w-40 oil. I pointed out that in the case of his car's engine, being air cooled, that the heat of the thicker oil was just adding extra heat load the cooling system had to deal with.

While he admitted he had noticed fuel comsumption went up when he switched from 0w-40 oil to 15w-50 oil and even his track times got a bit worse he was adamant about sticking with 15w-50 oil.

However your example I think is flawed to some degree. Dropping the transmission from 6th to 5th and holding the same vehicle speed this of course results in higher bearing speeds which can result in heating the oil up more. But the engine is making more power strokes too which puts more heat into the pistons which is removed by the oil sprayed onto the under side of the pistons the oil delivered by the oil jets and of course one can't distinguish which source contributed the most heat to the oil.

By running the oil at a lower temperature (I like "250F" as the max temperature) one has some extra margin of safety. With no guidelines from any real authority -- like Dodge who could possibly have some as I suspect it has collected some telemetry from its test mule cars and their engines and just as important direct access to the "real authority" (at Pennzoil) regarding Pennzoil 0w-40 oil -- while I like 250F another person could easily like 260F or higher even 300F.

But as I said above I like a bit of a cushion, a safety margin, and will avoid subjecting my Hellcat's engine to oil temperature above 250F and unless I track the car probably the highest oil temperature the engine will experience is 230F.
 
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