Sorry if you feel stalked, I've no recollection of commenting on one of your posts before. I just post when I think I can add something useful.

When the engine is running there is constant airflow through the inlet system and the inlet charge absorbs some heat from the block and inlet manifold, but not much as it's not in contact for very long before it goes bang.

The intercooler has to deal with the heat generated by compressing the air in the turbocharger, and cool the inlet stream as much as it can. Cooler is better, within reason: a massive intercooler will get you lower inlet temperatures but the extra cooling may be outweighed by the weight of the cooler itself. The fact that some heat will be absorbed from the inlet manifold and the cylinder walls is factored into the ECU calculations.

Heat Soak in turbocharged cars seems to mean different things to different people (from a quick google and looking at other car forums). Many people talk of it related to intercoolers, where they reach a higher equilibrium temperature on hot days that results in poor charge cooling and reduced power.

The sensors in the inlet system read manifold pressure and temperature and feed them to the ECU, which can then work out very precisely the amount of oxygen in each cylinder-full of air and inject exactly the right amount of fuel, resulting in improved fuel economy and maximum power per stroke. The Mass Air Flow sensor next to the air filter is used to fine tune the map.

Spark timing is varied by the ECU all the time to give the best power delivery from each ignition cycle. It's one of the advantages of digital engine control, replacing the distributor which only allowed very crude variation of the spark timing.

As for my avatar; I've run diesels for a long time now, after having two successive Golf GTI's stolen and burned out. Currently running a Toledo TDI 150 Sport, whose badge is my avatar. Lovely car, looks completely innocuous, even the badge is tiny. I feel no need to make my car look different or sporty, I just want it to go when I need to. The Toledo delivers that very well. With a turbocharger.
 
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it's ok muttley me and you have had a discussion about heat soak before on a thread about which is best panel filter or open cone, if you can remember??, I'm always up for learning, cos in today's climate knowledge is power and also very helpful to friends and fellow members on here, i think me and you would get on really well if we ever meet, cos there's not many people who know what there actually talking about or who are willing to learn about things which can help themselves and others, i respect your knowledge and if I'm wrong I will admit it (not many people admit there wrong nowadays cos there's too many arrogant people!!), well I've learnt something today so it ain't a day waste d!!
 
Oh, yes, drilled airboxes.

You're too kind - I have no engineering qualifications (only an applied science degree, umpty-mumble years ago) but have been performing DIY engine mechanics since I could first ride a motorbike. There was less to go wrong then, but it went wrong more often. So I've got some relevant experience but I don't to this for a living, and don't have the exposure to a wide variety of problems and fixes that someone like Bill of Badger5 or MJ of Volksmaster has - listen to them rather than me for real-world experience.

Car systems today are very much more reliable, and very rarely go wrong (think how many cars there are out there and how few reports we get to see on the forums). Built-in diagnostics help a great deal too.

I agree completely about always being ready to learn. A lot of my use of the forums is to see what's gone wrong with other people's cars and how they fix it, just in case it happens to me.
 
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So with heat soak how much difference to heat soak (if any) would having the same sort of scoop you get on a scooby make. By no means would i do this I am just curious.
 
I know thats is why it is there , was just using the shape and location as an example mate but does having cool air flowing over and around the engine reduce heat soak at all or would it just be pointless exercise with reduction of aero dynamics ?
 
Ha yeah the scooby vent would be a def no no but if you were to create a lip about 30cm long where the bonnet catch is so there was air flowing in over the slam pannel. I realised heat soak affects my 01 lc alot when i took it for a power run. Apologies to YELLOVNI my last post seemed a bit irate.

Chappers next time you see him ask him his username. He could have bought the car at that power and has no idea what he is running etc, or just trying to show off to ya!
 
Dont worry about it next time ill get all internet tough guy on ya though so be warned ;)

On another note i did see a mk3 cupra with a renault 19 16valve chamade bonnet vent fitted just were the battery is so inline with the airfilter....didnt look stupid either.
 
that's good then, i would love to see some of the bodged one haha, I've never messed with anything like body kits so it's new to me, I prefer the OEM+ style
 
Liquid cooled engines rely on the radiator for cooling. Adding a vent to put extra air into the engine compartment isn't likely to help very much. It won't hurt, but I doubt it would be worth the effort or spoiling the looks of the car.