Hot weather track day issues

Hi all got my self another track booked up at brands tomorrow evening , being that set to be the hottest day of the year with a 35.c was wondering if there would be any issues to look out for or things for me to help prevent any issues . I have a single turo auto, was thinking of lower the boost and running at 1.1 bar

Is there anything i can to to help keep things cool or does it not really matter as im sure the states is hotter and they run just fine on poor pump gas ?

I have done a few track days at Brands Hatch with those kind of temperatures and the only thing I had to keep an eye on was the coolant. Make sure you take at least 5 litres spare with you. I run the car on R888's and on a hot day they become quite sticky and the grip is increased so you have to adjust your driving style.

Great track, I have booked a track day on the 27th. August.

Lower the boost a bit. Do proper warming up and cooling down laps. If you are going to run full boost then get some ethanol (max 5 litres) and put it in with a full tank - will keep the burn temp down and avoid detonation/pre-ignition.

As its evening I would not worry about it so much as it will have cooled off by then. Id be more worried about you overheating than the car

sweet thanks for the input guys , Think I will drop the tyre presure abit too and take plenty of water for the car and myself

Llast hot track day My Mx5 started life as an Mx5... By 1pm I ditched the sidelight pods, headlamps (left them popped up), taped in a cardboard deflector to get more air to the radiator AND ehater son full-blast just to stop it boiling like a kettle after 5 laps. Keep a few bottles of water & a tin of coolant handy. When you come off the track at the end of the session leave your engine running with the handbrake off (check paddock is flat first...) for a few minutes to let the engine cool down with coolant running through it

Tyres by the end of the day were like sandpaper, lots of knobbly bits and car covered in bits of rubber so may be worth getting some paint pro before you go on.

I'd advise upping an oil grade too if possible, i did the stupid thing of using 5w30 Castrol GTX... Ideally should have used 10w40 Castrol GTX. No damage just when the oil got hot & thinned out the hydraulic lifters were tapping a bit.

All above on MX5, no experience with Supra just some precautions in my own experience.

EDIT go with a full tank of petrol, you'll be surprised how fast it goes

track day went well sort of , after 10 minutes of hard driving the car was over heating as soon as I stopped the over flow tank was boiling over , this might be down to me sorting a water leak the other week and just topping up with water as I didnt have any coolent to hand at the time , or it could be that it was a just silly hot , note to self must recharge air con black car with windows inched down in 35 degrees is rediculous

The air con on will not only sap power, but will make it more likely to try and overheat. Does it have a front mount intercooler? They definitely do no favours at all to water cooling. Radiator duct binned, another matrix in front of the water rad exuding heat and blocking air flow.

Is the proper undertray in place? they help air flow out of the engine bay. Has it got the stock viscous fan and fan shroud still? Stock rad?

Never had that kind of overheating trouble in the 5 years I've been tracking the Supra.

Had to fit a power steering cooler alright, but the water temp is always sub 100°C.

Didn't have overheating in my car with new stock rad/cap and viscous with the fan shroud, also had an R spec fmic stuck in front.

Temps weren't this hot thought and only around 25 c air temp

Also the more water the better the cooling, the coolant is there for corrosion resistance and it's antifreezing properties so your topping up of water won't be the cause.

The main thing is what did the temp gauge read. I always had same symtons as yours on track days, water gushing out from the overflow tank but the temp needle would always stay in the middle. I was scared that I might blow the cylinder head gasket so I have installed new rad cap, water pump and the radiator.

The first test is on 27th. August at Brands Hatch.

I never put on the air con.

The air con on will not only sap power, but will make it more likely to try and overheat. Does it have a front mount intercooler? They definitely do no favours at all to water cooling. Radiator duct binned, another matrix in front of the water rad exuding heat and blocking air flow.

 

 

Is the proper undertray in place? they help air flow out of the engine bay. Has it got the stock viscous fan and fan shroud still? Stock rad?

Okay i will list what i have as im sure some dont help

stock good as new auto radiator

ducted front mount

transmission cooler in front of rad

air con rad

no under tray at all

stock viscous fan with shroud and electric fan ( electric fan didnt come on or i could not hear it)

rad cap of 0.9

temp gauge went up to about 3/4 maybe a touch more , never had any other issues with over heating in normal hard road use , but 10 minutes flat out it couldnt take it to be fair i even got your fast road pads smoking like crazy

is there a deeper issue do you think?

Also the more water the better the cooling, the coolant is there for corrosion resistance and it's antifreezing properties so your topping up of water won't be the cause.

It also raises the boil point but im not sure if that helps of not

 

stock good as new auto radiator

ducted front mount

transmission cooler in front of rad

air con rad

no under tray at all

it would seem that there is a lot of layers before the radiator all of which will be wanting to cool so the air each see will be getting progressively hotter and less able to extract heat, especially with Chris saying the lack of an undertray will hold up the flow out too.

Undertray, then a stock type side mount intercooler and the transmission cooler in the other side duct might resolve the issue?

The fact the OVERFLOW tank was venting may have just been enough expansion in the main rad occurred to push some coolant out of the overflow tank. if the gauge was only reading as you say I would have carried on, brake pads aside

FMIC's and air con rads all hinder air to the water rad. The stock rad and stock fan, in fact stock everything coped on some very hot days on my auto TT, and I was lighting my fag off the front discs in the pits, but the Jap spec brakes had full race pads and SRF fluid. The engine cooling system coped just fine. Maybe 10 consecutive laps as fast as I could pedal the old girl.

I thought that having no under tray would help with cooling the engine with the air being to pass the oil pan ?

would a stock rad cap of 1.2 of helped ?. will fitting a under tray help ? how what i know if there was a underline issue ?

must admit i think i will flush my cooling system a good few times to get it complete clear /clean

Just to note any persons searching for hot weather track days, it would be a good idea to unplug the water temp sensor at the bottom of the radiator by the drain plug , this is the temp sensor for the auxillary fan/s disconnecting it will bring the fan on when the ignition is switched on , for an auto user this will be the first thing I do next time as the fan is situated by the stock auto cooler,

For some reason mine did not come on , so in my search for testing found that if you unplug the sensor it switches it/ them on, looks like my sensor is bad as my fan come on but didnt on my track day when my overflow was boiling over.

All modern car aerodynamics and engine bay hot air exit is very carefully designed, the undertray is a very important part of front end aerodynamics. The radiator exit air flow should go down the tunnel to a large extent.

I doubt the auxiliary fans will make much difference to on track cooling. It / they are piddling little things, and are more for aiding idle speed, stationary in traffic air flow through the rads with A/C turned on. Ram effect and the huge air flow capabilities of the viscous coupled main engine driven fan should be more than enough even on a hot day. having sid that i drive my engine driven fan in my GTS-t at water pump speed (viscous removed) as history tells of Nissan having cooling issues in the saloon car championship with Skylines on hot days. Such was their supremacy back then the loss of a few BHP driving the fan at full speed were irrelevant.

I wouldn't fit a higher pressure cap unless the heater matrix is either now or bypassed, these are known weak spots and an original one may not like the increased pressure. If you have to do this to raise the boiling point then things are obviously marginal anyway.

Are you sure the Otter switch (base of rad aux fan switch) opens when the coolant is hot? I had in mind they closed, but I am not 100%.

100% Normally closed and open when hot, I checked in the manuals

looks like I will be off to wicks for a sheet of prespecs

If you ask at Wickes for a piece of Perspex they may be less perplexed

I am surprised by how the switch works, as I don't recall the fan running if I forget to plug it in. But I am pulling a rad today, I'll have a look, thanks!

HAHA I know I cant spell for toffee

it is a odd way for a electrical circuit to work for sure , for it to work it must be holding a relay closed all the time which would shorten the life of the relay but im sure toyota had a reason . ( I have not looked at the wiring diagram so may have some funky stuff going on ).

It may use the ECU for solid state switching, or a latching relay that holds its state after a brief pulse to the energising coil.