Engine Temps

[turbotom]

You're running a manual, so I guess you haven't got a trans cooler.

In your situation, I would place a large capacity, high flow through oil cooler, in front of the IC where it gets first grab of the cool incoming air.

I have my trans cooler ( Maxiflo 600 x 110 x 15mm (w x h x d) ) fitted in front of my APS IC, behind the top opening of the BA grille.

Trans temps drop 30 degrees C with this cooler, and as it is a very high flow through system, plenty of air gets through to the IC and the radiator.

Don't forget, if the engine oil is cooler, there will be less stress on the (water) radiator to maintain temps. For track work in a T, I would seriously consider an oil temp gauge if you haven't already got one.

Water temps are one thing.... oil temps are not the same.

By the way, also check your thermostat. I found my 82deg thermostat was faulty a couple of weeks ago. Just dunk it in some boiling water and make sure it does open. Mine was remaining closed.

Now all is well again.... 40 degree Adelaide weather last week, and car engine oil temp at 80 deg C...... but it does climb if pushed continuously.

Engine oil cooler is the go......

Some form of thermostatic control would be useful too, as a 30 degree drop from nominal op temp is NOT good either if running on the street in winter.

tom

[bcl]

Ben,

How many laps were you doing in each stint?

I say this because when I used to do wrx supersprints we'd do no more than 3 laps each time out. If you do a lot more laps each time out, especially on a hot day, it'll put a lot lot more stress on all components with continued heat build up.

As for cool down after a stint we'd always go for a 3 to 5 minute slow drive.

Our advice from the experienced guys was never just park the car after a hard stint, as there's a good chance the rotors will warp, through heat build around the brake pads.

Brian

[937]

This is a bit off topic.

The specs for an F1 Engine

V8 , 2.4 litres, about 750hp, Piston speed 40 metres per second.

Uses about 65 litres per 100km.

Cooling water temp 115 C

Oil temp 100C

[937]

Guys I have had the front bar off a few times and there is heaps of room behind the foglights.

If you remove both foglights, you could put a trans cooler on one side and the oil cooler on the other.  You would need to put some exit holes on the plastic inner guard, but it will mean you can hide it nicely.  Remove the foglights and you have a large intake with pleanty of cool air.

As for the removal of the rubber seal at the firewall, I think it is a good idea, but I remember reading somewhere that if you do this it can cause pressure problems under the bonnet.  Apparently the seal creats a high pressure void under the bonnet and the heat escapes under the car.  Removing the seal upsets this flow of air and can lead to overheating.

I guess you could also try what the ricers do and put a few washers on the bonnet bolts to lift the bonnet up a few mm.

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isnt putting washers on the bonnet same as removing the back rubber seal? you are playing with that high pressure void under the hood?

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And this from Volvo.

[937]

How to keep an F1 car cool

Essentially, the need for cooling is a product of the inherent inefficiencies of the internal combustion engine. Even an advanced modern F1 engine is relatively inefficient when it comes to converting the power available from the fuel/air mixture into power at the rear wheels. This is measured in terms of 'thermal efficiency', and is typically in the region of 30%: that's to say, if a typical F1 engine produces slightly under 650 KW (approx. 850 bhp) on the dyno, something like 1500KW (or potentially 2000 bhp) of the energy is lost.

So where does it go? A small percentage is turned into the distinctive sound of an F1 car. The vast majority, though, must be dissipated as heat from a number of areas: for example, the oil dissipates around 120KW and the water system 160KW. The inefficiencies of the gearbox will mean it has to dissipate around 15KW, while the hydraulics represent a further 3 KW. However, as much as 34% of the remainder is lost through the exhausts as heat, while up to 15% of the available energy can be accounted for in unburnt fuel.

Moreover, this energy wasteage provides significant challenges when it comes to controlling temperatures. While the heat exchangers on a racing car are extremely efficient, their ability to cool the engine is a function of the 'air-side capacity' - essentially, how big a mass of air you can make flow through the radiator for a given area. This depends, of course, on generating high air velocities in the radiator intake ducts: however, typically, air velocity in the radiator ducts will only be 10-15% of the car's velocity, so even if the car is travelling at 300 kph, the air in the ducts is probably only at 30-35 kph.

Furthermore, temperatures in the oil and water systems vary according to different criteria: water temperature is a function of the average power used around the circuit, while oil temperature is approximately a function of power and also average engine speed around the lap.

Given how complicated cooling management is, you need a good reason to tackle so many contradictory problems, and that reason is aerodynamics. Essentially, we must find the correct balance between cooling and aero performance because the more air we channel through the radiators, the less efficient the overall aerodynamics become. In fact, changing between minimum and maximum cooling can reduce downforce by as much as 5%, which translates to a lap-time deficit of around 0.4s on an average circuit.

Airflow is controlled by different configurations of radiator outlet, and the R24 has 13 different possible configurations to cope with all manner of conditions. The configuration used at a particular circuit is defined according to the ambient temperatures, 'circuit factors' such as how much full throttle is used, and the temperature limits we can run the engine at.

Typically, we will run oil temperatures of over 100°C, while pressurising the water system at up to 3.75 bar allows the boiling point to be delayed until around 120°C: running these higher temperatures means we require less airflow through the radiators, thus improving aerodynamic performance. As ever, though, these choices carry a penalty: each extra 5°C of water temperature we run, allowing the radiator outlets to be smaller, robs the engine of over 1 bhp.

However, the importance of aerodynamics in modern F1 means we continue devoting significant resources and wind tunnel time to cooling. This is nowhere better illustrated than by the fact that the penalty in terms of aero efficiency we must accept for a 10°C drop in car temperatures, is 80% smaller than it was just four years ago.

[F6 UTE]

bcl, It's hot after 2 laps.. mild weather, maybe 25 deg. Mind you, I've lost brakes after 2 laps aswell.. Running very good fluid aswell.

I always do 1.5 laps cool down, and the rotors are under 200 deg when I'm back in the pits..

I put the heater on max, fan on max too.........

[XR06T]

I put the heater on max, fan on max too.........

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whats the theory behind this?

[F6 UTE]

I put the heater on max, fan on max too.........

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whats the theory behind this?

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Well the heater gets it's energy from the passing coolant. If you put the heater on, it transfers the heat from the coolant to the cab. I think it also lengthens the amount the coolant travels, as it has to go thru the heater core.. So it takes longer before it gets heated up again.

It's gets like a sauna in there, but it will cool your car down quicker than just idling, or going slow.

I was sweating profusely, but atleast it maintained a constant of just under 3/4 on the gauge.. Enough to dice with a GTR for ~12 laps.. We had a cool down lap in the middle, but it still went ok, no brakes though, thank god for the R-comps..

[XR06T]

I put the heater on max, fan on max too.........

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whats the theory behind this?

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Well the heater gets it's energy from the passing coolant. If you put the heater on, it transfers the heat from the coolant to the cab. I think it also lengthens the amount the coolant travels, as it has to go thru the heater core.. So it takes longer before it gets heated up again.

It's gets like a sauna in there, but it will cool your car down quicker than just idling, or going slow.

I was sweating profusely, but atleast it maintained a constant of just under 3/4 on the gauge.. Enough to dice with a GTR for ~12 laps.. We had a cool down lap in the middle, but it still went ok, no brakes though, thank god for the R-comps..

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thanks

[RAP1D]

While I was trying diferent intercoolers a few weeks ago, I left the plastic under tray thing off and noticed the water temp go to the half way mark from just normal punting around in the afternoon heat.

Its back on now and temps are back to normal, accually the gauge reads a fraction higher but the radiator is now almost totally cover by the intercooler.

Are you guys using the tray still? Ive seen plenty of T's without it.