Is The Hot Weather To Blame?

[HRthirtyone]

on my new engine, i am runnning a new thicker radiator with standard shroud and engine fan, also front mount and the performance in 30+ degrees is still good. water temps are down, which in turn keeps everything under the bonnet that bit cooler. I would recommend covering the basics i.e. good cooling system and intercooler before setting up some sort of spray system on a daily car.

Having said that, you should still keep the boost low on a real hot day on your daily just as a common sense thing.

[Cubes]

Once engine coolant temps get up the ecu begins to retard ign. timing.

Unsure what coolant temp that is on the stock ecu but on the R33/R32 GTST pfc's its from 80degree's.

The GTR PFC begins retarding ign timing from 90degree's.

[Munkyb0y]

engine temp wasnt an issue, according to the stock engine temp gauge.

more to do with the heat affecting intake temps methinks.

re: bov. i have a full plumb back gfb. gives me no probs.

[Cubes]

Regarding the stock temp guage.

The stock water temp guage is basically a 3 stage. Cold, operating then HOT.

For example mine see's half at ~70 degree's right up to ~110degree's where it only just starts to move up towards the H.

On hot days in traffic without the a/c on I generally see around 90degree's. With the A/C on in traffic it gets up around 95 and has seen 100degree's on those 40+degree days. Once the traffic gets moving temps quickly come back down to around the mid 90's.

I've never had any issues with heatsoak and what not. BUT I still run the stock airbox and have a great big dirty 100mm cai entering the box from the left inner bumper.

[Abo Bob]

Mine said half when I hit 109 on the track the other day.

[Munkyb0y]

great !!!

well i wont waste anymore time looking at that gauge

[700HP-GTR33]

best way to get decent performance in summer is a waterspray intercooler jet. I have had great sucess with this.

I had a cefiro a couple of years ago that was set up for drift and saw a lot of track work in summer and it was also my daily driver.

I had a temp probe lust before the throttle body to measuer intake temps.

When I first got the car in summer with the stock cooler I saw temps of 60deg + then I put the FMIC on and saw an drop of about 10 to 15 deg.

but I was getting pinging on really hot days. so I decided to fit a waterspray system. All it really was was a windscreen washer motor/bottle with a hose going to the front of the cooler that directed 4 water mist nozzles on the front of the cooler. It had a check valve to stop it from siphoning out of the washer bottle. It was triggered by a pressure switch from an old washing machine that was set to 4psi.

As soon as you started to boost it the system would switch on and spray water in a fine mist onto the cooler. It was amazing it dropped intake temps to about 5 to 10 deg above ambient. and stopped the engine from pinging. I am going to do the same mod this summer on my new car and will do a writeup for those interested. All up it cost about $70 for the patrs and a bit of fiddling but its a really good mod. you just have to remember to fill up the bottle every time you fill the car as it only lasts for about a 300k's with spirited driving on a small scource.

Firstly,

How did you get the washing machine into an engine bay?

And the way I drive I would need a 20 litre tank of water for my FMIC so,

Put the washing machine in the back seats and the 20 litre of water in the front passenger seat.

That way you can wash your clothes and not get thirsty .

[Cubes]

Mine said half when I hit 109 on the track the other day.

Its quite scary how quickly it goes from half to the H.

A 3 stage stock temp guage is good, nothing worse than a swaying temp guage.

109degree's is ok, over 120-125degree's is where the coolant begins to boil. :S

[Munkyb0y]

well if my coolant temps were up there, then that would explain alot.

and here i was thinking it was just intake temps.

[Kennedy]

CAI Box with adequate ducting from below. Game Over

[Munkyb0y]

yes, when you're on boost in the stinkin summer heat.

but how does this help coolant/engine temp?

is it a combo of both that's causing grief in the heat?

Edited October 18, 2006 by Munkyb0y

[Godzilla32]

Ok ive possibly got the answer for your hard starting issue. I was recently at a work training course for EFI diagnosis. If the day/s before you try to start the car is a real stinker the ECU will record all this data and have the system set accordingly. If then you try to start your car the next morning in a cool condition/engine IE:garage/shade/early morning it is more than likely going to have trouble starting with the new data the ECU has logged from hot daily driving. To see if this theory is correct try pulling out the ECU fuse for a few minutes to reset it.

Hope this helps

Deren

[Munkyb0y]

now that's an answer. sounds quite plausible to me.

and that's exactly how it happened. parked it right after a 1hr drive in the stinking heat. started it the next morning in much cooler temps, inside a garage, in the shade.

[Munkyb0y]

here's a theory about CAI. it's not my theory, but makes sense to me.

i'm sure it was mad082 (prease confirm) that said this in a thread somewhere.

intake air goes through the turbo where it proceeds to get hot, because the turbo is hot. so cool air or warm air will turn to hot air anyway.

so isnt it better to have an unrestricted pod that can take in as much air as it needs, rather than reducing it's supply of air by boxing it, in the hope of reducing temps by a couple of degrees?

mad082, correct me if i got it wrong.

[mad082]

it was me.

[mad082]

i would like to see someone with a temp sensor in the cold intercooler pipe to test this theory. having a sensor on the airfilter doesn't mean much. i'd like see the difference after the intercooler.

[Munkyb0y]

i would like to see those results too.

but it totally makes sense that as hot as a turbo gets, it will always heat up the air that passes through it.

[mad082]

and if the turbo is running at 90 degree (using it as an example) then the air would get heated up to 90 degrees whether it enters the turbo at 30 degrees or 20 degrees.

[Godzilla32]

Apparently for every degree you reduce the intake air temperature you gain 1 Hp. The pod filter shroud is probably more beneficial on a non turbo engine as they dont have/need intercoolers.

Just because the turbine is stinking hot doesnt mean it will directly heat the charge air to the same temperature. The air rushes through there so fast it would barely be heated by the turbine next door. Its the compression of air that causes friction between atoms which in turn causes alot of the increased heat.

[GeeTR]

The air rushes through there so fast it would barely be heated by the turbine next door. Its the compression of air that causes friction between atoms which in turn causes alot of the increased heat.

Thanks Godzilla, i thought i was going crazy! "turbo heating air due to radiant"