OIL and HEAT do I actually need a cooler?

[andlid]

OIL and HEAT do I actually need a cooler?

 

AS the subject above, there was a discussion on the Chat between myself, NeilP and ceaser...

 

It became clear that ceaser is of the opinion that its not needed to get a cooler for the track newb only for someone doing tons and tons of laps around track and if you are running a FI setup.

 

NOW please argue this point.

 

[Ian]

It's cheap safety. Why wouldn't you do it?

[andlid]

It's cheap safety. Why wouldn't you do it?

because I'm told its not needed with fully synth oil.

[Ian]

who told you that?

 

My oil temp has dropped by 30degrees since installing my cooler. Its cheap insurance, you'd be mad not to do it imo

[Neilp]

a small discussion for more discussion

" from an oil point of view, it has been proved beyond doubt that there is absolutely no reason why y cannot runa car at 7000 revs 0.75 seconds after start up "

[andlid]

eh you cant cut and post stuff from the chat like that dude...

[Ian]

Is he suggesting, that you can give a car full revs right from the start??

[Neilp]

yeah matey... might go try it

[HaydnH]

I use always let my car warm up properly and don't use it on track - wouldn't an oil cooler just make me wait longer for the engine to warm up and have little to no benefit in my case?

[Neilp]

the oil cooler sandwich plate is thermostatic so only opens when its needed. what u see on the dash is the water temperature, not the oil

[andlid]

Just waiting for input from Ceaser now.

[Ian]

 

Not my fault

[andlid]

the oil cooler sandwich plate is thermostatic so only opens when its needed. what u see on the dash is the water temperature, not the oil

not all of them have that though so be sure to inform that you want one

 

 

Not my fault

nope not your fault.

[Neilp]

any thoughts on this from anybody else.... its really a very interesting discussion and has now got me wondering...

 

any mechanical engineering pro's out there who know anything.... any thoughts

[andlid]

any thoughts on this from anybody else.... its really a very interesting discussion and has now got me wondering...

 

any mechanical engineering pro's out there who know anything.... any thoughts

so you dreamt about oil viscosity then? Shame Ian made a b*lls of things yesterday thought we had a decent argument goings on.

 

yo Ceaser can you please post!?

[pptom]

I would have thought that any oil operates in an optimum temperature range, too hot + too thin and too cold = too thick would both have negative effects. But, as long as the cooler was thermostatically controlled, and the thermostat was set to the correct temperature, and working properly, there shouldn't be any problems.

If you're really concearned, buy a sandwich plate and oil temp guage and do some monitoring.

[Neilp]

lol it has been annoying me all night matey

[andlid]

lol it has been annoying me all night matey

I would have thought that any oil operates in an optimum temperature range, too hot + too thin and too cold = too thick would both have negative effects. But, as long as the cooler was thermostatically controlled, and the thermostat was set to the correct temperature, and working properly, there shouldn't be any problems.

If you're really concearned, buy a sandwich plate and oil temp guage and do some monitoring.

Well I've been told that it's not good to have an oil cooler on at all times on a road driven car, that is then adjusted by using a thermostat... I'm asking do I actually NEED one. It's more for an healthy argument really.

[Neilp]

I would have thought that any oil operates in an optimum temperature range, too hot + too thin and too cold = too thick would both have negative effects. But, as long as the cooler was thermostatically controlled, and the thermostat was set to the correct temperature, and working properly, there shouldn't be any problems.

If you're really concearned, buy a sandwich plate and oil temp guage and do some monitoring.

according to caeser im sure he said oil thickens when it heats up do to viscosity somethingmanuthers

[andlid]

I would have thought that any oil operates in an optimum temperature range, too hot + too thin and too cold = too thick would both have negative effects. But, as long as the cooler was thermostatically controlled, and the thermostat was set to the correct temperature, and working properly, there shouldn't be any problems.

If you're really concearned, buy a sandwich plate and oil temp guage and do some monitoring.

according to caeser im sure he said oil thickens when it heats up do to viscosity somethingmanuthers

yeah depending on the breaking point and such... can't remember, interesting all the same .

[ceaser]

hello all

 

this 'debate' stemmed from a conversation in the chatroom last night. Now i dont normally get angry with people but after having qualified with a degree in materials science, worked in the oil business for years testing developing and researching oil, to be told i dont know what im talking about by someone who plays around with their 350z as a hobby before returning to their day job as an accountant/van driver/whatever, is somewhat annoying!

 

So, ive decided to share a few 'oily' facts with you all about what i picked up when working in the research dept for Exxon (aka esso), the worlds largest petroleum manufacturer. Now im certainly not a mechanic, or tuner but i do know probably more then is healthy about what happens to oil inside an engine, in fact for any insomniacs out there, ive still got some old tribology textbooks laying about which could help you

 

I will divide it into two parts, oil facts (not opinion) and a favorite which always brought a smile to the staff tea room - aftermarket oils. This could be a long post - you might want to go get a cup of tea !!

 

oily facts

oil isnt a magical thing, its designed to prevent metal on metal contact in your engine thus preventing wear, seizure and all the other horrible things which could happne in the engine environment. Now most damage to engines happens on start up, so oils over the years have been formulated to circulate very rapidly even when cold to provide complete protection. The main advance in this is PAO based oils aka full synthetics.

 

now most oils are mineral based, ie pump crude out of the ground, refine it, blend it and sell it. PAO is 'made' it isnt refined crude but is chemically manufactured. It is a completely different beast to the stuff you grew up with and im afraid all that knowlege you may have picked up, be it from your dad or by being in the 'motor trade' for xxx years is a bit out of date. Im going to focus on what is in our cars ie fully synthetic oil.

A modern full synthetic provides complete circulation to and protection of critical wear parts in less then a second of cold start up. How do i know this? well there were a fleet of cars at esso driven in cold start cycles, for months then stripped to constituent parts, checked, measured for wear etc etc. So yes, from an OIL point of view, within 1 second of use, you can rev your car to 7000 rpm. you have complete protection, there will be no wear on critical parts, proven tested fact - end of.

 

A PAO oil doesnt need 'time to warm up' A film of sufficient strength and thickness is fully coating your cars internal workings in under a second. How does it do this? well older oils go a bit solid when cold and can break up when hot, PAO just doesnt do that. now i could go into lots of depth about branched chain hydrocarbons etc but basically the chemical make up of PAO allows it tailored to perform exactly as needed. Now car manufacturers have been told this, R. Lobo, one of the heads of esso research wrote to tell a major manufacturer all about the results of the esso ultra (pao oil) products, and was told thanks but no thanks, we are still going to limit cars when cold 'just in case' . Well its no skin off Nissan to hedge its bets, after all, if they make the wrong call, replacing a million engines isnt cheap! Now, im not a mechanic, it could be that the plasma drive of your flux capacitor needs time to develop thermal bridging etc etc which is why most car manufacturers limit their cars rpm when cold. But it is certainly not a requirement from an oil point of view.

 

Now the ability to 'tailor' PAO to what you need allows you to use less additives. oil in your car is made of two things, basestock (the oil or blend of oils itself) and the additives put in it (addpack) The additives enable oil to operate over a wider temp range by modifying the viscosity(multigrade sound familiar?) they alter the pour point, oxidation rate, act as detergents and water inhibitors, increase the anti shear properties, and a whole host of other 'wonderful' things. With PAO being such a good basestock, it has these properties inherently 'built in' to it. It has much better heat transfer properties and because PAO requires less additives (typically this can be up to 20% of a mineral oil but less additives mean less to break down = less to go wrong) they deteriorate less. Now to head off the 'yes buts' i have deliberately kept this at a high level, i will include some links at the end for those who wish to 'immerse themselves in oil' chemisty at a greater depth.

 

so what does this mean for us 350z drivers? Well lets see...

I change my oil every 3000/5000 miles to prevent wear! arnt i good!!!

Er no sorry, your equating what your dad taught you/xxx years of being in the trade and always doing it like that as how you should behave. What you have to remember is that you are using a premium grade product which has been tested to death both in labs and in actual thousands of hour engine tests and found to be safe and provide complete protection for 9000 miles. the 5000/whatever mile limityou are used to and consider 'safe' might be fine for an old cortina using mineral based oil but things have moved on since then. How do i know this, well from testing actual cars, pulling engine oil samples, checking for wear etc in tests which could last 25000+ miles!! Remember, Nissan dont want any engine recalls or liabilities on their hands they wouldnt put these reccomendations on without SOILD FACT AND TEST RESULTS behind it. But at the end of the day its your money, if you want to throw away perfectly good oil to make yourself feel better then go for it. (and for the person who stated he changes his every 1000 miles Please put it in a can and send it to me, i could do with a supply of perfectly good free oil!)

Yes but Nissan reccommendations dont apply to me because its MY CAR and im SPECIAL, in fact im such a baddass driver that im THE STIG

er right ok, so Nissan lauch a completely impractical 300BHP (well, mine is ) 2 seat sports coupe and expect it to pootle around the shops whilst being driven by my great aunt doris?? Really?? they hadnt considered for one minute that people who buy these cars might like to give them some stick??? hmm lets see, does 155mph, rather large brakes, big tyres etc etc, it must all be for show right!! Sorry to disappoint but even your stig like driving style has been anticipated, simulated, tested etc etc. in fact a safety factor has been built in as well, PAO is perfectly capable of surviving all types of driving styles alot longer then 9000 miles. lets say a mondeo has a service point of 12000 miles on the same oil, reducing the service point to 9000 gives you a 25% safety factor purely to anticipate your hooligan driving style!!!

Yes but my car is modified and i need a special oil/cooler etc etc

two questions you have to consider, 1, are you running FI? if not then 2, what exactly do you think your mods have done to the oil and the way it performs?? is your engine revving harder, ie 9000 rpm?? if not then the oil (not the internals which sufer mechanical stress etc, remember im no mechanic) doesnt really care what mods you have on your car! how can it, its primary purpose is to act as a very thin buffer between moving parts. if you havent added any more moving parts, ie turbo or supercharger, or increased the frictional forces on the oil, ie increased the rpm, then what do you think your mods are going to do to the oil, well i can tell you - nothing! Shearing forces or excess heat (deal with that in a minute) damage oil. Bhp or torque doesnt damage oil, it doesnt care. its only concerned with being constantly rubbed between the mechanicals!!

 

Now FI is a different beast, oil doesnt like FI, it scares it, it makes its little black heart tremble!! This is due to the massive shearing forces put on oil by a high RPM spinning turbo. This leads to the oil being under intense frictional forces and subject to much higher heat transfer rates then normal, especially combined with a much smaller engine which makes it harder to shed heat from. but yet, PAO has been specifically designed to operate in that environment and survive, albeit not as long, though i do beleive EVOs are now up to 8000 miles service? So, you have an oil designed to survive 8000 miles in an evo where it is put under massive pressure , basically it gets its nads thrashed for 8000 miles and you then put the same oil in the nice friendly environment of the big engined non turbo low revving 350z. Still worried about your oil???

 

Oil coolers. EVOs have them, GTRs have them so we need one right?

er no, not really. in fact you can do more harm then good. for all those thinking about an oil cooler, what exactly do you hope to gain? A PAO oil is perfectly stable up to 200 deg C (for all the yes buts, go look it up if you have doubts) Without the high heat transfer rates small FI engines impose on an oil your oil just wont get hot enough to chemically break down to warrant one, in fact, cooling your oil too much can be harmful for daily driving. For the person who said "oh, it cant harm to have a cooler, better to be safe - my oil is now 70 deg c temp!" er how are you get rid of the water in your super cool oil?? Fact: Water is absorbed into oil. they dont mix and what you get is an emulsion. additives are used to limit the damage this causes but a good way to get rid of water is to boil it off. a nice hot oil (100+ deg) will drive that bad water out! the last thing u want in your engine is emulsion, it damages film formation and leads to excessive wear. mayoneise on the underside of the oil filler cap a good sign? i think not! yet thats what you will get if your oil isnt hot enough to shed the water. And i havent even began to mention all the biological nasties which like to live in oil, nasties you wont kill off unless you heat the oil hot enough, which breed and breed to clog up all your filters ...... (Luckily PAO isnt mineral based)

Ah but i do a few track days a year so my car gets really reeeealllly hot, in fact if i dont spend hundreds on cooling, oil drains etc etc my car will EXPLODE and the WORLD WILL END and we will be INVADED BY WOMBLES !!!

Ok i cant help with the wombles part but do you really think on the track the pressures on oil are that extreme? Oil starvation through accelleration aside, which is a different issue (we have firmly established by now, i hope, that im not a mechanic) what extremes do you think you are subjecting the oil to? remember this is the same product that you wll use quite happily when cruising down the motorway at 4000+ rpm, perhaps for a couple of hours (untill you run out of fuel), maybe on the way a small tangle with a porsche at 3am on a non public road as well, oo er, 6000 rpm !! sound familiar??? Yet who panics over their oil after such a trip??? surely that oil must be super hot by now but do we rush out to buy a cooler and change the oil after such a trip? No, we dont, in fact you probably jump in the car and do the same thing all over again, loads of times before each oil change. And what happens with such 'abuse' ? any sign of the wombles??? i think not!!

 

lets look at some fag packet calcs - my favorite kind! You use your Z for an hour a day and at the end of the hour, car very warm by now, you give it some stick, you manage to find an open road and really open it up, maybe for 5 whole minutes!!! So for 5 minutes per day, lets say 6 days a week to make the calcs easy your car is subjected to track like forces temps etc etc as you cain it cause for those 5 minutes YOU ARE THE STIG!!!

Now changing your oil once per year (9000 miles) gives us 1/2 hour per week x 48 (to allow for holidays ) = 24 hours of track equivelant driving abuse you subject your car to in the course of a year. hmm lets be generous and half that, I will allow you 2.5 mins whole minutes of stig like driving a day

so what do we have, well we have 12 hours of looney driving (12 track days? ) plus the rest of your 9000 allowance of high rpm motorway driving, cold stop starts etc etc and yet, the cars dont explode!! As long as you follow the servicing intervals the cars are fine!!Wow, could this be the reason that a cooler of any significant size was never included in the first place ???

 

Now im not saying this applies for those who have their cars towed to a track, spend hours testing , racing etc etc etc, but a little quote i found might shed some light..

"At Bathurst in 2002 when the winning HRT Commodore was running with a blocked radiator inlet the oil temperature rose to above 200°C yet the engine not only survived in perfect condition, it won the race."

hmm blocked rad inlet? oil cooler not working perhaps??? PAO is good stuff eh!

Now with my limited mechnical skills i wouldnt dream of telling a tuner how to set up a car and if a tuner says you need a cooler, all well and good - tuners, whilst being very wise in things which make cars go fast, are not experts in oil degredation. they can only gain this knowledge by monitoring the oil, checking after each race the physical properties to assess wear and oxidation rates - there is no other way of doing it- i certainly couldnt tell you how 'far gone' an oil was without lab testing! They are protecting themselves and advising you what is best on a race car - all well and good. But a pampered trailored maximum rpm on every use race car is NOT A ROAD CAR!!!! If you do a few trackdays then drive home and pootle to work etc then you have a ROAD CAR not a race car!!! So for all you serious trackheads out there, is your oil over the maximum operating temp of the oil? if not then you have nothing to worry about. There are no yes buts only fact or not fact; the oil has been tested at continued use, max operating temp and has been proven to be ok - thats how the max operating temps are defined in the first place!!!If it exceeds this then you may need to bring it down, or change to a different oil, im sure i remember seeing some designed with max operating temps of 250+ deg c

 

right, off to the shops, will post part 2 some other time. for those who disagree with the above comments, good for you! im not going to spend the rest of the weekend arguing or or answering 'opinions' If you have a different opinion or , like the two last night, think the post is complete rubbish, i dont really care at the end of the day its your car, your money - do what you like with it!

for those who would like to know more, here are a couiple of links (no doubt there are loads out there) i have just found which explain in more depth and elequance (and less spelling mistakes) then i have

happy reading!

 

http://www.mobil.com/Australia-English/ ... ineral.asp

http://www.synthetic-motor-oil-change-a ... synthetic/

[dyla350z]

Good read

[Ian]

Ill reply fully when i get home but my car is FI so that answers your dig at me

[andlid]

NO need for the personal attacks but enjoyed reading that. In part two can you talk about oil brands please. I'm putting on the kettle.

 

So is having a cooler that kicks in at 90 degrees going to actually cause damage to the engine ?

[djtimo]

I have done tons of research on this guys. The optimum oil temp for engine life is between 86C and 102C. This was done on a porsche engine test ring over 300,000km. Motul 300v 15w-50 is stable to over 150C for endurance racing but at this temp the oil wedge on the bearings becomes very thin and extra wear is happening.

 

My oil cooler set up was working to well so I have blocked off air ducting to get the car HOTTER. Colder is not better.

 

If you like your car then keeping the oil about 100C on the road and the track is best. I have run up to 137C with no oil cooler but why do that when an oil cooler for a few £££ will keep you down in the optimum range?

 

So messing about andy and get one!