Engine Oil Temperature

[ACR128]

Hi everyone, this is my first post in the forum.

Since I had my ACR 1:28 a year ago, I have tracked it for 7 times.
Its equipped with ARH headers with no catalysts, stock mufflers and Arrow racing PCM. I’ve changed the OEM engine oil cooler lines with aftermarket lines. And am running Motul 5W50.

I always keep an eye on “engine oil temp” and “coolant temp”. After two or three moderate laps at Yas Marina Circuit, the engine oil temp is reaching almost 230-240F. When I compare it to my friend’s stock 2013 GTS, after 8 laps he is barely reaching 215-220F. (Outside temp 77-90 F) (coolant temp: ~210-220)

I asked few friends about it and they’re saying am over worried about it. But my only concern the oil temp is rising really quick within few laps.

Anyone had this before?

[stradman]

Hi everyone, this is my first post in the forum.

Since I had my ACR 1:28 a year ago, I have tracked it for 7 times.
Its equipped with ARH headers with no catalysts, stock mufflers and Arrow racing PCM. I’ve changed the OEM engine oil cooler lines with aftermarket lines. And am running Motul 5W50.

I always keep an eye on “engine oil temp” and “coolant temp”. After two or three moderate laps at Yas Marina Circuit, the engine oil temp is reaching almost 230-240F. When I compare it to my friend’s stock 2013 GTS, after 8 laps he is barely reaching 215-220F. (Outside temp 77-90 F) (coolant temp: ~210-220)

I asked few friends about it and they’re saying am over worried about it. But my only concern the oil temp is rising really quick within few laps.

Anyone had this before?

Try running a different oil. In the past on track(before I went to 9.0L) I did find I had increased temps when it was hot outside say 30 degrees. And funny enough I was running Motul 5w50. I can't say whether that was the cause but now I run mobile 1 10-60 and never have problems with temp on track. Worth a try perhaps.

[BSLSK]

This thread would be worth the read for you https://driveviper.com/forums/threads/28436-Which-aftermarket-oil-cooler-are-you-using?highlight=hubbell

I'd also have to agree with Stradman. You should try running 15W-50 as that is the proven oil weight for tracked Vipers.

[Lawineer]

Hi everyone, this is my first post in the forum.

Since I had my ACR 1:28 a year ago, I have tracked it for 7 times.
Its equipped with ARH headers with no catalysts, stock mufflers and Arrow racing PCM. I’ve changed the OEM engine oil cooler lines with aftermarket lines. And am running Motul 5W50.

I always keep an eye on “engine oil temp” and “coolant temp”. After two or three moderate laps at Yas Marina Circuit, the engine oil temp is reaching almost 230-240F. When I compare it to my friend’s stock 2013 GTS, after 8 laps he is barely reaching 215-220F. (Outside temp 77-90 F) (coolant temp: ~210-220)

I asked few friends about it and they’re saying am over worried about it. But my only concern the oil temp is rising really quick within few laps.

Anyone had this before?

240 engine oil temp is fine. Just run good oil like Motul 300 or Royal Purple or something.
Plenty of cars run +260 EO temps all day long with no problems.
Honestly, at those temps, 5W50 may be too thick.

You're probably just faster than your friend is all.

[Arizona Vipers]

240 is fine, I get to 260 all the time. You probably hold 2nd gear longer than your friend.

[Gen5snake]

Also keep in mind that your friends GTS isn't fighting all the downforce your ACR is. Your engine is working harder.

[serpent]

Op, how hard are you running the car, if your friend has low oil temps are they even running fast times?

I always think about that when someone says their oil temps are lowyet they are 20+ seconds off the record time at laguna seca, 1:28 record, while they're clocking 1:50 which is pretty slow.

[Lawineer]

Also keep in mind that your friends GTS isn't fighting all the downforce your ACR is. Your engine is working harder.

They're both (assuming equal driving) working just as hard. The engine is making 645 hp- GTS or ACR with a parachute. There is a difference, but probably insignificant and isn't because it has more drag. The ACR is, in theory, faster through the turns, so it spends more time in the straights under high load and gets on the gas earlier and brakes later and blah blah blah. None of that really matters though. Long story short, it's a timed session, not a distance thing so it's the same engine going WOT then down to zero, a little throttle and WOT again over and over and over again for equally as long so it won't much matter.

Would be interesting (though a complete waste of time) to compare ACR vs GTS gas mileage.
Would also be interesting to compare brake pad wear too. I bet the ACR uses a tiny bit more even though it has the help of drag.

At the end of the day, I almost guarantee it's driving. It's like when people on Corvette Forums tell me they tracked their Z06 and it has no overheating issues while I'm watching good drivers get to 300 degrees on lap 2.

[RedTanRT/10]

ACR128, lot's of good comments above. My comp coupe can run as high as 260 on a hot day in the California desert. Much has to do with; outside temps, type of track and gear selection. Like other's have mentioned, you should run 15-50 oil, not sure why you'd be running 5-50 in Dubai? BTW, the Corvette guys get oil temps up to 300 or more.

[darbgnik]

240 is fine, I get to 260 all the time. You probably hold 2nd gear longer than your friend.

Good point. When we ran our local track in reverse, I spent twice as much time in second gear, with much higher oil temps.

[98intrigue]

Another thing to note is there's been evidence that the Arrow PCM gets the oil temps up quicker/higher than the OEM PCM. Not sure if you feel comfortable swapping back to the OEM PCM to compare given your mods though.

[pMak26]

These modern high quality oils can run up to 300*f without major concern. 240*f is nothing. Just makes sure you do more frequent oil changes when running 250*+. The protection at those temps is absolutely still there, but they do not last as long. I forget the exact ratio but it's something like oil service life will be reduced by one-half for every 10°C (~18°F) increase in temperature over the base value (~220*f) due to oxidation.

[txA&M08]

I see 260* oil in Houston in the summer after 5+ laps. Lots of 2nd gear on my local track, and I have the Arrow PCM, which I doubt helps as Ryan mentioned. I run 15w50 as well.

[Old School]

These oil temps got me wondering, since the oil temp sensor is after the cooler, what's the oil temp before the cooler?

[Lawineer]

These oil temps got me wondering, since the oil temp sensor is after the cooler, what's the oil temp before the cooler?

Higher.


That is odd though. It's the sensor normally in the pan? Or am I misremembering? I'm guessing I'm misremembering because otherwise the car would be really hot cruising arond.

[GTS Dean]

At high loads, your oil is probably doing as much cooling as the radiator is. Good oil has more capacity for heat than radiator coolant.

[Gen5snake]

They're both (assuming equal driving) working just as hard. The engine is making 645 hp- GTS or ACR with a parachute. There is a difference, but probably insignificant and isn't because it has more drag. The ACR is, in theory, faster through the turns, so it spends more time in the straights under high load and gets on the gas earlier and brakes later and blah blah blah. None of that really matters though. Long story short, it's a timed session, not a distance thing so it's the same engine going WOT then down to zero, a little throttle and WOT again over and over and over again for equally as long so it won't much matter.

Would be interesting (though a complete waste of time) to compare ACR vs GTS gas mileage.
Would also be interesting to compare brake pad wear too. I bet the ACR uses a tiny bit more even though it has the help of drag.

At the end of the day, I almost guarantee it's driving. It's like when people on Corvette Forums tell me they tracked their Z06 and it has no overheating issues while I'm watching good drivers get to 300 degrees on lap 2.

I'm a mech engineer...There is no question the ACR engine is working harder...especially at max velocity. There's a reason the ACR has a top speed of approx 29 mph less than a SRT base. That down force will allow that ACR to do better with corner grip, but regardless of trajectory, there is a price for that increased downforce...resistance. Resistance is felt throughout the drivetrain...causing more friction. Friction is heat. The engine and oil cooling is the same on both cars...I'm not surprised to see an increase in oil temp with the ACR.

[Arizona Vipers]

They're both (assuming equal driving) working just as hard. The engine is making 645 hp- GTS or ACR with a parachute. There is a difference, but probably insignificant and isn't because it has more drag. The ACR is, in theory, faster through the turns, so it spends more time in the straights under high load and gets on the gas earlier and brakes later and blah blah blah. None of that really matters though. Long story short, it's a timed session, not a distance thing so it's the same engine going WOT then down to zero, a little throttle and WOT again over and over and over again for equally as long so it won't much matter.

Would be interesting (though a complete waste of time) to compare ACR vs GTS gas mileage.
Would also be interesting to compare brake pad wear too. I bet the ACR uses a tiny bit more even though it has the help of drag.

At the end of the day, I almost guarantee it's driving. It's like when people on Corvette Forums tell me they tracked their Z06 and it has no overheating issues while I'm watching good drivers get to 300 degrees on lap 2.

There's a lot more to it then that. You are correct in a lot of ways, but the ACR will be seeing slower trap speeds on all straights, so less cooling is happening. The ACR will also have to be at 100% throttle longer and more often to reach the same speeds in the straights. If you are seeing 10mph less on the longer straights, the ACR will see much less radiator cooling as well as having to be full throttle longer to reach the end of each straight.

[usmcfieldmp]

Every way that I think about it, I have to agree that the load on the ACR engine should definitely be higher (AKA it's working harder). The load on the drivetrain is increased due to the extra "weight", which will load up the engine more. It'd be like driving up a steep hill or towing something.

[ACR128]

Try running a different oil. In the past on track(before I went to 9.0L) I did find I had increased temps when it was hot outside say 30 degrees. And funny enough I was running Motul 5w50. I can't say whether that was the cause but now I run mobile 1 10-60 and never have problems with temp on track. Worth a try perhaps.

I tried to run OEM 0w40 and it was heating up really quickly within the first lap. Not bad advice, definitely am gonna try it out 10-w60. Thank you

[ACR128]

This thread would be worth the read for you https://driveviper.com/forums/threads/28436-Which-aftermarket-oil-cooler-are-you-using?highlight=hubbell

I'd also have to agree with Stradman. You should try running 15W-50 as that is the proven oil weight for tracked Vipers.

I think 15 is a bit thick for a stock engine. It would be running good to H/C or 9.0L. Thank you

[ACR128]

240 engine oil temp is fine. Just run good oil like Motul 300 or Royal Purple or something.
Plenty of cars run +260 EO temps all day long with no problems.
Honestly, at those temps, 5W50 may be too thick.

You're probably just faster than your friend is all.

Thank you and for sure am gonna try different oil.
Currently am using Rowe 5w40 and was pretty good for two laps at the Track (+105F outside temp)

[ACR128]

240 is fine, I get to 260 all the time. You probably hold 2nd gear longer than your friend.

Never thought about it and now it makes sense. My only curious is why its raising so quickly within few laps. I thought maybe something wrong with the cooler or lines I’ve changed.
Thank you

[usmcfieldmp]

I think 15 is a bit thick for a stock engine. It would be running good to H/C or 9.0L. Thank you

The 15W is really only concerning cold start and it's rated for below freezing temperatures.

The 50 is the part that you should really be concerned with when debating on-track lubrication.

15W50 is generally seen to be applicable for freezing temps up to 50°C (ambient temps).

[Lawineer]

Every way that I think about it, I have to agree that the load on the ACR engine should definitely be higher (AKA it's working harder). The load on the drivetrain is increased due to the extra "weight", which will load up the engine more. It'd be like driving up a steep hill or towing something.
Driving a Jeep uphill will have more load on the engine because you're adding more throttle. GTS and ACR will both be WOT on the straights from roughly the same start point to the same end point. The ACR will just be carrying more corner speed and start to get on the throttle a tiny bit early and brake a little later- but that's all negligible for powertrain cooling purposes.

WOT is WOT for the engine. It doesn't have more or less load to cool being uphill or downhill. It's making 640hp and pumping about 640hp worth of thermal energy into the fluids. Up, down left or right, or stationary on a dyno.


There's a lot more to it then that. You are correct in a lot of ways, but the ACR will be seeing slower trap speeds on all straights, so less cooling is happening. The ACR will also have to be at 100% throttle longer and more often to reach the same speeds in the straights. If you are seeing 10mph less on the longer straights, the ACR will see much less radiator cooling as well as having to be full throttle longer to reach the end of each straight.

I doubt there is much more cooling at 110mph vs 100mph. 10 vs 20 mph, sure, but after a while, it doesn't really matter. I'd guess that somewhere around 70mph it increased air velocity doesn't matter. You're only going to get so much air through a radiator- especially one with an electric fan on the back of it. Plus you run into boundary layers (thermal and laminar boundary layers) and other fluid dynamics stuff.

Only thing that really matters is total energy output over the 20 minute session.

There are other factors, such as average RPM (friction) but I'm assuming that on the same track, that will be similar.


edit:
https://www.engineeringtoolbox.com/convective-heat-transfer-d_430.html
https://www.engineeringtoolbox.com/docs/documents/430/air_heat_transfer_coefficient.png
(20meters per second is about 45mph)

That's over a flat plate, which is a big different, and I think (thought not certain) it would be much more pronounced (as in, flattens out faster) where flow is restricted like going through a bumper inlet.

[usmcfieldmp]

That makes sense to a degree, but I was thinking of it more that the extra load on the drivetrain translates to the crank being harder for the piston/rod combination to turn, which should lead to increased friction losses. It's an interesting question. I probably just need to sit down and think about it for more than 5 minutes.

[Lawineer]

I get what you're saying, but I dont think that is significant. There ARE different drivetrain losses in different gears, but it's not going to have any more or less drivetrain loss due to having more drag. The energy in gets turned into "acceleration" (kinetic energy) instead of friction. But I think the extra load/energy loss almost all going to be put into the air, not the transmission.

Now if the transmission had a brake pad in there causing it, as opposed to a giant wing, that's another story ;) Resistance in the drivetrain should be the same. Likewise, Jeep gonig uphill converts energy into kinetic and potential energy rather than just kinetic.

edit: the reason cars get hot with high loads going up steep hills is because 1) they use lower gears and 2) they go slower, but most importantly, they use more throttle!

It's always just an energy equation. Heat is nothing more than energy. So if the engine makes the same amount of it, the radiators have to work just as hard.
Drivetrain loads are a bit different, but their "load" is really just what the engine puts on them. Think about it- does a truck transmission get hot if you put 10k lbs in the bed if you dont run it? Its load (force) comes from the engine.

All a transmission does is taking a Force at one velocity and output another force at another velocity (or the same for one gear).
Force * Velocity in = Force * Velocity out.
F*V = power = in lay terms, basically the rate of energy.

Obviously, there are a million other factors here, but when we're talking about oil temps, stuff like that is in the noise (again, assuming other stuff is constant).

[Arizona Vipers]

WOT is WOT for the engine. It doesn't have more or less load to cool being uphill or downhill. It's making 640hp and pumping about 640hp worth of thermal energy into the fluids. Up, down left or right, or stationary on a dyno.


Correct. And the ACR will be WOT more/longer than a regular viper on track. It will take longer to cover the same distance on the straights. Remember top speed is 29mph lower, the drag is massive, the ACR will be on WOT much longer on every straight.

[Lawineer]

Correct. And the ACR will be WOT more/longer than a regular viper on track. It will take longer to cover the same distance on the straights. Remember top speed is 29mph lower, the drag is massive, the ACR will be on WOT much longer on every straight.

Two things
1) I bet the ACR gets through almost all straights faster because it runs faster lap times- even if top speed can be lower. It's going to carry a ton more corner speed and have a lot more exit velocity. Maybe COTA or something like that would be different, but given it runs much faster lap times...

2) If if it spends more time in straights (which is difficult to do and still run faster lap times), then it goes into the next turn and goes WOT again. It CERTAINLY gets through the turns faster and can brake later, so it's spending less time off throttle too. It's not like there is a finish line. It's going to go WOT over and over again for 20 minutes.

My guess is they have a very similar on throttle/off throttle ratio. I would guarantee it wouldn't be enough to make much of a difference in powertrain fluid temps.

[ViperSRT]

Impossible to determine without full track data. WOT power is not a constant. It changes with rpm. So the vehicle that averages higher rpm while at WOT will have more heat expended. So a lot depends if the faster car, assumed to be the ACR with its higher corner exit speeds, needs to upshift and the other one doesn’t some place around the track. Doesn’t have to be the highest straightaway.

[Lawineer]

Of course, but that kind of stuff is in the noise for overall fluid temp.

[StrokerAce]

48861

[ACR128]

Thanks everyone for their comments, help and support. One or two month left for the season to start in Dubai, once i go back to track I post feedbacks for sure.