[MINIMANIAUK]

For those who have tuned or thinking of tuning their MINI please consider the effect on their engine: to gain more power you must flow more air, this extra air must have extra fuel therefore the combustion temperatures will increase. HEAT kills engines.
this excess heat is taken away by the water cooling system ,the water system was designed around stock power levels -not tuned power levels.
the MINI sprays oil under the piston to cool the piston crown,great design,but the oil now has to cope with greater temps, the oil is cooled by a water heat exchanger so the water system already stock also has to cope with the extra oil heat as well.
modern synthetic oils cope very well with the heat ,but the cooling system will not, every 1000 rpm will require about 2.5 times the oil cooling requirement,so a high rpm track day car MUST have extra oil cooling,like wise a high power car.
Heat management is vital in any car,more so in a tuned one,ever smaller pulleys and higher intake temps will not help,the cost of extra cooling is not high,especially compared to the cost of failures ,plug tip failures,piston failures,gasket failures,and block /head cracks will all spoil your day.
it is not by chance that cars designed for the German autobahns have oil coolers fitted!
it is not unusual for the cooper s oil to exceed 120 degrees c
sorry to keep on about it ,but I read the wish lists of people on here and never is extra cooling mentioned or specced or advised

[herbie hind]

Quote: Originally Posted by MINIMANIAUK (original)

For those who have tuned or thinking of tuning their MINI please consider the effect on their engine: to gain more power you must flow more air, this extra air must have extra fuel therefore the combustion temperatures will increase. HEAT kills engines.
this excess heat is taken away by the water cooling system ,the water system was designed around stock power levels -not tuned power levels.
the MINI sprays oil under the piston to cool the piston crown,great design,but the oil now has to cope with greater temps, the oil is cooled by a water heat exchanger so the water system already stock also has to cope with the extra oil heat as well.
modern synthetic oils cope very well with the heat ,but the cooling system will not, every 1000 rpm will require about 2.5 times the oil cooling requirement,so a high rpm track day car MUST have extra oil cooling,like wise a high power car.
Heat management is vital in any car,more so in a tuned one,ever smaller pulleys and higher intake temps will not help,the cost of extra cooling is not high,especially compared to the cost of failures ,plug tip failures,piston failures,gasket failures,and block /head cracks will all spoil your day.
it is not by chance that cars designed for the German autobahns have oil coolers fitted!
it is not unusual for the cooper s oil to exceed 120 degrees c
sorry to keep on about it ,but I read the wish lists of people on here and never is extra cooling mentioned or specced or advised

i'm running the madness cooler. but with a slightly bigger setrab and a thermostat from mocal? 180f . the madness is a good adaptor with 1/8" npt plugs for temp and pressure. though the temp is on the out bound side. but if i'm to see a pressure drop from a remote line i guess the incoming line would be the one i'd pick. i lost a line last summer due to it blowing out(i used the wrong lines) all heavy duty race stuff but wrong i.d. so i took a chance it'd last another day as there was no indication of a problem. well ' now i'm looking at at the very least an overhaul. but no biggy ; it beats smoking and gambling and such. right? want a new head anyway. so a balanced crank will set things off nicely .!!

[HObzy]

Should I be worried then that my very modded S never goes beyond normal driving temps despite a whole days blasting away at Goodwood in the summer? Is my oil temp gauge broken lol? It always moves steadily up to halfway and sits there happily no matter what.

[herbie hind]

Quote: Originally Posted by HObzy (original)

Should I be worried then that my very modded S never goes beyond normal driving temps despite a whole days blasting away at Goodwood in the summer? Is my oil temp gauge broken lol? It always moves steadily up to halfway and sits there happily no matter what.

you've got an oil temp in an s ? you installed it then?

[MINIMANIAUK]

water temp and oil temp are not really linked,you should have an oil cooler for any track work and also replace oil more frequently

[HObzy]

Ahem sorry meant water temp... too much wine with dinner...

Still same question though - if the water system doesn't cope, wouldn't the water temp gauge rise too? Or am i being REALLY thick. (Still learning the mech' side of things so a helpful answer rather than a flaming please ) About to upgrade all the hoses under the bonnet to Samcos so will it make sense to add the extra oil cooler at the same time? Don't like my pet mechanic to get bored

[HObzy]

Also meant to say the oil has been changed every 3 track days... Is that enough?Any particular oil you recommend BTW?

[MINIMANIAUK]

No you are not being thick, there is a connection between the water and oil , a small heat exchanger about the size of a fag packet ,but this is more about using the water (which heats up way faster than the oil) to heat the oil on cold starts,than cooling the oil, the water temp is about 100degrees (fan at 102) and the oil temp is usually below this at normal speeds,however at higher rpms(racing)the oil temp rises way above this,and the heat exchanger not big enough and does not have sufficient temp difference to adequately cool the oil.
cooling the oil has many benefits (although too cold is not good,hence water heat exchanger) the hotter the oil the thinner it becomes,this can have an impact on the main engine bearings at high speed and under high load,also the cooler the oil sprayed under the pistons the more heat taken out from them, its the combination of high rpm/load/and temp that kills engines, that and detanation- the dredded D word !!! det is still not fully understood ,but it is still an engine killer especially in tuned engines with altered boost and timing(remaps) heat has a lot to do with detanation,but also head design and flow ,and fuel octane,strangely it occurs more at the midrange rpms and reduces at the higher ones,another good reason for a 4-2-1 manifold ensuring good airflow extraction.

Modern synthetic oils cope very well with high temps,far better than minerals, I use mobil one,principly because they invented it and deserve to be rewarded for it! they also cope well with low temps- why did MINI use the water heat exchanger? to warm the oil a) its good practice and design for emissions and economy b) you cannot guarrantee that the owner is not using cheap mineral oil.

[MINIMANIAUK]

The water cooling system, is set at manufacturers to run the engine at a set temp,modern engines run hot, why ? because the emissions are critical and legislation/taxation and green issues are popular. if the engine is run even hotter the economy improves but the emissions increase, conversely if it is run cooler the power increases but both econony and emissions rise, so the running temp is set by design for a standard car. if it is tuned the engine temps rise loading the stock cooling

[Haggi]

interesting my cooper donsent get used for track days but gets driven quite viggerosly most places how would this likey effect the long term of the engine ?

[MINIMANIAUK]

The cooper being normally aspirated and making less power generates less heat ,the step up in power is usually from 115 to around 140 or so and the addition of a exhaust/ manifold /head all help in removing heat from the engine so less critical. the engine block and head is identical to the cooper s which is now being pushed up to over 120 bhp more on top of that,with added boost pressure,
larger or more efficient intercoolers help greatly but the heat is not totally eliminated and a lot of it simply transfered into the engine bay area,

[MiniBimmer]

Hello
Very good post, Congratulations...

I have the Oil Temp in my MCS JCW and the temperature normally is between 80º and 90º, but when I pull and in transit goes up easily for 100º.

I´m thinking about put a better Intercooler and Samco coolant hose kit. Do you think this helps reduce the temperature?
The 4-2-1 manifold is a good modifications for reduce the heat?

Best Regards

[HObzy]

Thank you for your in depth answer MM - very helpful cheers.

I've been lucky enough to become friends with a good mechanic who rather than just take my money, is helping me learn as go as we fit each successive mod to the car, so its been a big learning curve for me. Good advice is always welcome.