Is running a motor at 300 degrees too much
12-06-2005, 05:09 PM
#3
Team Owner
No, it is just fine if you have a ton of money or a sponsor. 
You also don't have to woory if you lose some HP when hot.
No problem here
Next time I'll know it's not from the oil temperature. I had to rebuild the tranny and get a new diff 
That was one of the better pistons. 
You also don't have to woory if you lose some HP when hot.No problem here
Next time I'll know it's not from the oil temperature. I had to rebuild the tranny and get a new diff That was one of the better pistons.
Last edited by John Shiels; 12-06-2005 at 05:22 PM.
12-06-2005, 05:19 PM
#4
Le Mans Master
Incidently - I think you could make the thread really interesting
if you narrow the topic down to say 300º with synthetic oil.
After all, anyone who thinks 300º with mineral oil is ok, doesn't really
deserve the time of day.
.
if you narrow the topic down to say 300º with synthetic oil.
After all, anyone who thinks 300º with mineral oil is ok, doesn't really
deserve the time of day.
.
12-06-2005, 08:04 PM
#7
Team Owner
three or four years ago I had a H&C and was spanking my car fairly well. Then oil would hit 300-310 so I put a band-aid over the DIC 
so I would see it. I also remembered the Mobil 1 in the frying pan and said I'm go to go.
One day they whole thing went bang. Not really it was just a rumble on the infield of Pocono North course. Every thing locked up and I skidded off the track. Funny thing the camera was rolling and I didn't even yell any profanities. I knew it was over and I couldn't ask any more from an engine. When they went to tow it was locked up even with the clutch in. They dragged it to the side and the weekend was over as in was pouring Sunday morning. Wrecker came and dragged it up on the trailer which was at the track for the first time.
Every thing was wrecked, engine, tranny, and diff
I am severe on all equipment so I figured if I am going to continue to run it hard I better call DRM for all the coolers
We installed a new crate motor and did a new H&C. Now when I run the car it is cool. I would come in pre-coolers and I couldn't check the oil without a glove and it made all kinds of noises as it cooled. I run the car harder than ever and it is cool and no noises when cooling. NASCAR starts to panic at 260-65 and say what you want they are no fools.
I am sure the oil was fine when my motor blew it didn't burn but it has to take a toll on a motor. Race cars don't run coolers to add weight.
so I would see it. I also remembered the Mobil 1 in the frying pan and said I'm go to go. One day they whole thing went bang. Not really it was just a rumble on the infield of Pocono North course. Every thing locked up and I skidded off the track. Funny thing the camera was rolling and I didn't even yell any profanities. I knew it was over and I couldn't ask any more from an engine. When they went to tow it was locked up even with the clutch in. They dragged it to the side and the weekend was over as in was pouring Sunday morning. Wrecker came and dragged it up on the trailer which was at the track for the first time.
Every thing was wrecked, engine, tranny, and diff
I am severe on all equipment so I figured if I am going to continue to run it hard I better call DRM for all the coolers
We installed a new crate motor and did a new H&C. Now when I run the car it is cool. I would come in pre-coolers and I couldn't check the oil without a glove and it made all kinds of noises as it cooled. I run the car harder than ever and it is cool and no noises when cooling. NASCAR starts to panic at 260-65 and say what you want they are no fools.I am sure the oil was fine when my motor blew it didn't burn but it has to take a toll on a motor. Race cars don't run coolers to add weight.
12-06-2005, 08:07 PM
#8
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Tribology 101
300 degrees is on the upper limit on a synthitic oil. Most base stocks are from PAO's or a blend with esters.
The only difference in brands is the additive package, for the most part.
Keep in mind , the lower the viscosity, the better the fuel mileage and HP. Why do you think car manufacture's are recommending lower viscosities in new vehicles (ford 5w-20), CAFE standards.
Lower viscosities also transfers heat better. Having said that, high perforance driving does require a higher viscosity grade due to the heat that is generated.
A good solution for track use is to use a 5w-40. The only problem is I would recommed changing the oil at sooner intervals due to the polymers needed to make this differential, it will break down sooner , than say a 10w-30 synthetic (which has no polymers due to its natural viscosity index).
Also what is intersting, why do they recommend the same viscosity in Florida and Canada?
I am not recommending violating warraty terms, but to give some insight.
Wild Bill
The only difference in brands is the additive package, for the most part.
Keep in mind , the lower the viscosity, the better the fuel mileage and HP. Why do you think car manufacture's are recommending lower viscosities in new vehicles (ford 5w-20), CAFE standards.
Lower viscosities also transfers heat better. Having said that, high perforance driving does require a higher viscosity grade due to the heat that is generated.
A good solution for track use is to use a 5w-40. The only problem is I would recommed changing the oil at sooner intervals due to the polymers needed to make this differential, it will break down sooner , than say a 10w-30 synthetic (which has no polymers due to its natural viscosity index).
Also what is intersting, why do they recommend the same viscosity in Florida and Canada?
I am not recommending violating warraty terms, but to give some insight.
Wild Bill
12-06-2005, 08:16 PM
#9
Team Owner
I put 1500 track miles on 10 W 30 Mobil 1 last year and I was told after amylases to go 2500. My oil doesn't see anywhere near 300-310 anymore.
12-06-2005, 09:18 PM
#10
Melting Slicks
You should really title the thread 320 degrees. That is when the warning message comes on.
Now can we have a real discussion???
Something changed from C4 to C5. C4's were 300F, and C5's are 320F. I wonder what made GM change the temp limit ???? Did GM decide Mobil1 improved over the years, or was there an improvement in the motor internals to handle the extra 20 degrees ???????
Obviously GM decided to bump the oil temp limit another 20 degree's, and I doubt they did it without seriously researching it. Basically this is fact, there is nothing to argue over. It can be validated by looking at the dash
So please explain why the 320 limit, if so many of you are adamant over the 300 thing !!
ps: I am not bashing any company that sells coolers, and I simply stating opinion based on GM's engineering decision.
Now can we have a real discussion???
Something changed from C4 to C5. C4's were 300F, and C5's are 320F. I wonder what made GM change the temp limit ???? Did GM decide Mobil1 improved over the years, or was there an improvement in the motor internals to handle the extra 20 degrees ???????
Obviously GM decided to bump the oil temp limit another 20 degree's, and I doubt they did it without seriously researching it. Basically this is fact, there is nothing to argue over. It can be validated by looking at the dash
So please explain why the 320 limit, if so many of you are adamant over the 300 thing !!
ps: I am not bashing any company that sells coolers, and I simply stating opinion based on GM's engineering decision.
Last edited by the blur; 12-06-2005 at 09:20 PM.
12-06-2005, 09:29 PM
#11
Team Owner
I think the oil and the motors continue to improve but remember GM builds a street car not a race car or even a track car. Even a track car is subjected to this high temp many times. How har is it to get a C5 to 300 on the street? I think it is almost impossible unless you are on an abandon road and really killing it. GM does testing like 50 below then 130 above in the desert with all their vehicles which is a big range. Like their air cleaners they must work in a blizzard also.
12-07-2005, 10:24 AM
#12
Melting Slicks
I previously posted my motor disaster at VIR. It appears that the motor, a 112K mile motor, suffered oil starvation. Was it the 0W30 Amsoil I was running? Could it have been the old 99 model oil pump? WHo knows. I started fresh every track weekend and never had any loss of oil at the end of a day. We do know that one rod broke at the piston pin (#4 piston, right side, second from front) and another rod broke further down, pulling the piston into the pan. I had a hole big enough in the drivers side under piston #3 that you could put your hand in the block and pull parts out of the pan.
I was running an oil cooler. -10 lines, MOCAL unit, LGM Adapter. I don't think the cooler contributed to this failure. I believe that in my case the age of the motor, the miles on it, and the fact that it started a life with me at 92K miles, without a good prior history from previous owners contributed to the failure.
That said, I don't think 300 degree oil temps are what is the concern. Sure, synthetic oil can take it. But I don't believe for a second the rest of the parts involved can over extended periods without compromising the motor in the long run. NO, you won't "Melt" bearings, as was implied in the other thread. However, I do believe that the big chunk of aluminum (The block) that is acting as a heat radiator can only shed so much heat before it becomes over saturated and can no longer shed the heat. This over-heating causes premature wear on motor internals and can't help but also create fatigue on the block material itself. Will it hurt to do it a few times? Probably not anything you'll notice. Will it hurt to do it a lot? I personally believe it will, based on what I've been told by professionals in both the oil manufacturing business (Chemical Engineers) and those in the automotive engineering business and by metalurgists in the auto engineering business.
Mr. Shiels brings up another excellent point in referencing the NASCAR boys. They have big budgets and lots of sponsorship money on the line. They don't like to see anywhere near the oil temps we are happy with WITH coolers. Maybe it is due to the iron blocks they are forced to use, but I'm not counting on it. We all have steel cranks, rods and bolts, amoung other steel parts. All this steel stretches with heat and deflection is seen. Distortion of the metal is real, and heat saturation is real.
Maybe GM Figured that the aluminum block was sufficient to stave off the heat generated in extreme conditions (*Living in Phoenix Arizona for example), but I seriously doubt that they factored in the heat soak we're seeing at track day events. Who knows, Maybe I'm wrong.
Also factor in the failure of the traditional C5 batwing oil pan. That pan restricts oil flow. It is documented. It sucks... That is all I have to say about that!
We're gonna have as many opinions on this as we do brands of oil and brands of tire.
Mike
I was running an oil cooler. -10 lines, MOCAL unit, LGM Adapter. I don't think the cooler contributed to this failure. I believe that in my case the age of the motor, the miles on it, and the fact that it started a life with me at 92K miles, without a good prior history from previous owners contributed to the failure.
That said, I don't think 300 degree oil temps are what is the concern. Sure, synthetic oil can take it. But I don't believe for a second the rest of the parts involved can over extended periods without compromising the motor in the long run. NO, you won't "Melt" bearings, as was implied in the other thread. However, I do believe that the big chunk of aluminum (The block) that is acting as a heat radiator can only shed so much heat before it becomes over saturated and can no longer shed the heat. This over-heating causes premature wear on motor internals and can't help but also create fatigue on the block material itself. Will it hurt to do it a few times? Probably not anything you'll notice. Will it hurt to do it a lot? I personally believe it will, based on what I've been told by professionals in both the oil manufacturing business (Chemical Engineers) and those in the automotive engineering business and by metalurgists in the auto engineering business.
Mr. Shiels brings up another excellent point in referencing the NASCAR boys. They have big budgets and lots of sponsorship money on the line. They don't like to see anywhere near the oil temps we are happy with WITH coolers. Maybe it is due to the iron blocks they are forced to use, but I'm not counting on it. We all have steel cranks, rods and bolts, amoung other steel parts. All this steel stretches with heat and deflection is seen. Distortion of the metal is real, and heat saturation is real.
Maybe GM Figured that the aluminum block was sufficient to stave off the heat generated in extreme conditions (*Living in Phoenix Arizona for example), but I seriously doubt that they factored in the heat soak we're seeing at track day events. Who knows, Maybe I'm wrong.
Also factor in the failure of the traditional C5 batwing oil pan. That pan restricts oil flow. It is documented. It sucks... That is all I have to say about that!
We're gonna have as many opinions on this as we do brands of oil and brands of tire.
Mike
12-07-2005, 03:40 PM
#13
Le Mans Master
Originally Posted by the blur
You should really title the thread 320 degrees. That is when the warning message comes on.
Now can we have a real discussion???
Something changed from C4 to C5. C4's were 300F, and C5's are 320F. I wonder what made GM change the temp limit ???? Did GM decide Mobil1 improved over the years, or was there an improvement in the motor internals to handle the extra 20 degrees ???????
Obviously GM decided to bump the oil temp limit another 20 degree's, and I doubt they did it without seriously researching it. Basically this is fact, there is nothing to argue over. It can be validated by looking at the dash
So please explain why the 320 limit, if so many of you are adamant over the 300 thing !!
ps: I am not bashing any company that sells coolers, and I simply stating opinion based on GM's engineering decision.
Now can we have a real discussion???
Something changed from C4 to C5. C4's were 300F, and C5's are 320F. I wonder what made GM change the temp limit ???? Did GM decide Mobil1 improved over the years, or was there an improvement in the motor internals to handle the extra 20 degrees ???????
Obviously GM decided to bump the oil temp limit another 20 degree's, and I doubt they did it without seriously researching it. Basically this is fact, there is nothing to argue over. It can be validated by looking at the dash
So please explain why the 320 limit, if so many of you are adamant over the 300 thing !!
ps: I am not bashing any company that sells coolers, and I simply stating opinion based on GM's engineering decision.
Going over 300' once is no big deal, the idiot light is there so the average street user will know if something is seriously wrong and they need to pull off the road. Getting the temps up that high on a regular basis WILL shorten the life of you engine. Sure, your oil will be fine, but your engine can't handle it. All you'll end up with is good oil in a blown engine.
Look at the pictures of John's 1st engine -- what the hell do you think happened??????
12-07-2005, 07:06 PM
#15
Team Owner
I don't really know what did it but the whole engine was in no better shape than that cylinder. Doubt a NASA engineer team could figure it out. I do know a motor running oil temps of 215-220 will last way longer than one running 280-310 temps. The funny thing was no hole in pan or side of block. No oil on the track either.
12-07-2005, 08:42 PM
#16
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Smokey had it right!
You guys are all looking in the wrong direction. Smokey Yunick hit the nail on the head in his power book. Yes the synthetic oils are good to 300 degrees but the bearing babbit or what ever they call it today isn't. Add to the fact the oil temp at the bearing is 30 degrees higher than in the pan, Smokey's statement, not mine and you can see the problem. In addition last time I checked the bearing material starts to soften at these temperatures. I haven't looked a fluid dynamics book in years but the cause of the problem seems obvious. P.S. I always ran the biggest oil cooler I could fit on my C-4 race car along with dual accusumps and 9 qt pan. Never exceeded 250 degrees even in 100 degree heat. Never lost an engine, at least not due to an oil problem.
12-07-2005, 09:05 PM
#17
Le Mans Master
Originally Posted by John Shiels
I don't really know what did it but the whole engine was in no better shape than that cylinder...
The funny thing was no hole in pan or side of block. No oil on the track either.
The funny thing was no hole in pan or side of block. No oil on the track either.
ring lands, wrist pins and/or domes.
.
12-07-2005, 09:18 PM
#18
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Originally Posted by Randy@DRM
I made this new thread all about Oil Coolers.
Randy
Randy
12-07-2005, 11:42 PM
#19
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My bet is the food chain goes something like this...
320 on the oil briefly in and of itself is not the worry. At the hottest point in the engine is some aluminum that is running correspondingly hotter and you will start annealing it thus changing the properties of the head or block itself...enough of this and all bets are off...something you don't want to move will begin to move too much...get the cooler...live in happily in peace...
320 on the oil briefly in and of itself is not the worry. At the hottest point in the engine is some aluminum that is running correspondingly hotter and you will start annealing it thus changing the properties of the head or block itself...enough of this and all bets are off...something you don't want to move will begin to move too much...get the cooler...live in happily in peace...