Paolo,

Heat extractors in the hood would definitely help in your climate, especially with a turbo car. Anything that aides airflow in and out of the engine compartment can't hurt this car IMO.

 

Thnx Sieg,

I have noticed huge difference when driving in morning (cooler weather).

On weekend i left after midday and drove for close to 5hrs with a 20 minute lunch break into the sunset.

In first and second gear the car was sluggish. Was embarrassed to be beaten to 80km/h by other non turbo cars.

It was like driving the car without any turbo at all.
Quite bizarre as the 2.3L felt like a 1.3L engine..

Wish they had made vents for the bonnet. It really needs them in hot weather.

 

Thnx Sieg,

I have noticed huge difference when driving in morning (cooler weather).

On weekend i left after midday and drove for close to 5hrs with a 20 minute lunch break into the sunset.

In first and second gear the car was sluggish. Was embarrassed to be beaten to 80km/h by other non turbo cars.

It was like driving the car without any turbo at all.
Quite bizarre as the 2.3L felt like a 1.3L engine..

Wish they had made vents for the bonnet. It really needs them in hot weather.

The aftermarket can help you out.

Seibon HD16FDFO-RS Focus Hood Carbon Fiber RS-Style ST 15-17/RS 16-17

Anderson Composites AC-HD16FDFO-SA Focus Hood SA ST 15-17/RS 16-17

 

So "Heat-Soak" is waiting for me this summer....Hmmmn...

 

Thats the way it is with turbo cars. Bigger inter cooler helps but doesn't take away problem. On city driving it is even worse when there is insufficient airflow due low speed. Also there is probably some software kicking in to limit boost on hot conditions to prevent knocking.

Higher the boost is, more power you loose relative to air temps. To note also non turbo cars loose power in high temp conditions but not so much.
To understand what happens in hot conditions read following http://www.aet-turbos.co.uk/blog/st...k/blog/story/turbos-and-temperature-summer-weather-and-turbocharger-performance

There is severe chain reaction happening for how hot air is when getting in to combustion chamber. Hotter air means less oxygen molecules to react with gasoline.

Also mounting vented hood to your car doesn't really do anything for performance unless your engine is overheating. You just need to get cooler air in to engine.

 

Would removing the insulation under the hood help at all? I know that when the hood is down, it compresses the insulation above the air filter partially sealing it. I removed my insulation to hear more engine noise (which was noticeable), but possibly also allowing more air to be fed to the air filter? Worth a try?

 

I would not do this as you will melt your paint. This is a very common issue the mini cooper world as early mini coopers did not have hood insulation.

 

Paolo,

I have a number of friends who compete in the Optima Ultimate Street Car Series and run the TrackSpec louvers with good success.
Home page

Rousch Racing installed Mustang GT350 louvers in their RS at SEMA, looked great but appear to have somewhat limited venting compared to other options.

Here's few friends running TrackSpec louvers, most serious competitors in the series run some sort of evacuation louvering. Especially the C5-C6 Vettes as they'll bow hoods a couple inches at 140+ mph w/o louvers.

 

That Datsun...

 

That LS3 powered Datsun :smug:

 

I am a but surprised the RS heatsoaks so much, as its factory FMIC is pretty massive compared to the Subaru turbo motors I'm used to seeing. Even compared to BMWs turbo 6 engines, I feel like we have a decently sized IC from the factory.

 

Size isnt everything you know, but efficienty is. Look at some of the aftermarket intercoolers and you will notice they are around the same hight and length but about 60% deeper and have aluminium end assemblies.
So I'd imagine an aftermarket IC would help.
Does anyone run an intercooler fan for stop,start city driving? in hot weather? If so is it benificial?

Ciao

 

Thnx guys for the replies.

I may look at intercooler spray or even better new intercooler.
The stock is crap especially hot days stop start traffic.

The car wants highways open road to cool the intercooler. Will try the engine cover of this weekend and see what eventuates.

Definitely cold mornings and the car is raging. However, drive it in the afternoon hot and don't expect much in the way of boost.

What's surprised me most though, is how my old sti wasn't this bad with heat soak. The subby still had some boost..

 

I've been driving in 30C+ weather for the past week with A/C on and haven't noticed any change.......

 

My xr6turbo suffers the same issue in Sydney. Bonnet vents saw a reduction in intake air temp of 10C and reductiin in under bonnet temps around 20C.
Ventilation definitely helps, particularly letting the hot air out.

 

Sydney summers.. not the same as Melbourne summers.

Just curious hoping someone can answer this.

Why did they not feed cool air inlet to brakes also into the air filter intake?

If hot air enters the air filter intake what impact does that have? I recall someone fed an inlet pipe from front grille into the air intake. Looked weird but probably works.

 

The RS already has cold air intake standard. The airbox inlet is a ducted from above the radiator at the same point as the photo.

Ciao

 

Not sure if coincidence or not but the times I've noticed a drop off in performance seemed to be more humidity related than heat related. The performance drop isn't massive, but if you know what to look out for it is noticeable. I haven't taken the time to google the impact of humidity on turbo performance, perhaps there is none and there's a different reason for the variance I've experienced.

Hopefully as those of us down under slide into winter we'll enjoy a few months of stellar performance lol. Although I was lucky enough to get my RS while it was still quite cold last year, and I can definitely attest to it's savagery when ambient temps are below 18C.

 

Indeed..Thnx nishanj.
This x2

I have noticed this stickiness weather and it just sux. Especially going from coastal to inland where humidity varies.

Hoping the cooler weather will give us something to smile about. Can't wait. :thumbsup:

More reading here
http://rennlist.com/forums/991-gt3-...d-911r/878596-do-all-turbocharged-cars-lose-power-in-hot-and-humid-weather.html
https://passionford.com/forum/gener...al-car-related-discussion/60693-effects-of-hot-humid-weather-on-turbo-cars.html

 

Would this be a solution?
https://www.velossatechdesign.com/product/2016-2017-focus-rs-big-mouth-ram-intake-kit/

 

I live in Alabama, among the stickiest of the ickiest in humidity and temps. I haven't had any issues with heat soak. I have the ETS intercooler and charge pipes. Also, running with a Mountune intake if that makes a difference.

Recently I found an abandoned parking lot where I could hoon without interruption and didn't have any heat problems after 30 mins of abuse.

 

I'd thought i would reply since i created this thread.

About a month ago the car has been fed different fuel.

This has caused a big change one that I feel was causing this heat soak effect when i first wrote this thread.

So if you do experience a similar lack of ooomph, then change fuel.

Good luck everyone.

 

About a month ago the car has been fed different fuel.

This has caused a big change one that I feel was causing this heat soak effect when i first wrote this thread.

What fuel were you running originally, and what fuel did you change to that caused the lack of performance?

 

I went from this dodgy ****ty supermarket caltex to BP.

I will never change from BP ever.

The drone in 2nd gear is my key audible signal that the engine is truly combusting.

Previously no drone, lack of ooomph when pressing accelerator, and frequently feelings of limp mode like heat soak.

Now the car reacts every time i press.

I was on caltex since purchase last November. Now since mid August - BP

BP - better petrol and my engine agrees.
:thumbsup:

 

I'll have to try some BP and see if it makes any difference for my car. All of the Chevron and BP stations are owned by the same family in this area. I wonder what the difference really is as I believe they all come from the same tanks and what not? Different detergents added?

 

Listen for a drone in 2nd gear from rear exhaust.

This for me was definitely audible upon changing fuels.

Good luck everyone.
:thumbsup:

 

Picked up my car this winter (April 2017 build) and have mostly driven it at night in 4-5°C. Took it out yesterday to visit a mate, 20 minutes each direction, in 29°C, and there was no perceptible difference in full throttle acceleration. But perhaps 20 minutes per leg wasn't long enough to experience any negative heat effects.

(I have run the car exclusively on 98 octane fuel. Based on forum feedback I have settled on BP Ultimate after trialling a bunch of different brands [BP, Shell, Caltex, Mobile] in the beginning.)

 

Take it for a long drive >1hr .

I recall the early days, with the poor fuel, definite lag and feelings of heat soak.
Since going to BP, it's beastly.

:thumbsup:

 

Australia uses a different octane rating (RON) to the US. I believe 98 here is roughly equivalent to 93 in your neck of the woods.

 

Something I can really recommend because I lived with it for 6 years and have seen how useful it was.
A Mitsubishi Evo styled bonnet vent, the side ones are nowhere near as good, this I can guarantee you will let hot air escape from the bonnet, when I drove on track I could see the "desert mirage" like heat wave coming out of it and my bonnet was never as hot as for example it was on my mk1 RS Focus

it's placed kind of above the turbo and exhaust manifold on the evo btw