Advice on keeping a cold engine bay..

Shy19s

Oil running through my veins.
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Hey guys, just got back into the UK and been driving around recently and noticing a very hot engine bay..

I could go for a drive, stop somewhere and the coolant temp could still be up near 90 after 40 mins to an hour of me being in it..

how long after a boosting session do you guys drive off boost for, to let it cool down?

I've got a turbo timer that i usually leave on for about a minute after i turn off the ignition too..

Anyone know if immobilisors cut out the fan once armed?

Thanks in advance.
 
I would have thought that just from removing all the plastic covers in the engine bay you would be removing items that do a good job of preventing heat from escaping!!!!

Not the prettiest look but I'd bet you'd see a temp reduction
 
Thats all gone. long time ago.
 
Remove the bonnet :undwech:















PS. Sorry couldnt resist.
 
Don't know about the immobiliser.
For reducing the heat, then the obvious is vents/louvres. Could also try "jacking" the rear of the bonnet up to allow more air flow, removing the sound deadening stuff and engine covers.

I'll probably get slated for saying this, but I've been thinking of 'subtle' vents lately - maybe a thin one across the rear of the bonet for improved air flow or a small one in the bonet or side wing to line up with a cold air feed. :tumble:

Not thinking of scoops :undwech: just slots cut into it

I've also noticed that the engine bay's getting pretty warm this year!!

[edit] yeah, that website just put me off the idea actually!!
 
Last edited:
Just had another look at the web-site - it was gone 1am when I first looked and I was probably a bit tired, looking at the same / wrong thing everytime.

Anyway, the Golf in this pic is was I was thinking about (the standard grill that sits just below the windscreen wiper):
nov02-2.jpg


or something like that
 
HAHA, I wasn't messing about mate.

Yeah idealy you want a vent near the back like i the pick to let the hot air out and maybe a few louvres near the front to draw in so extra cool air.
 
Well, just been thinking, some F*&$%^^(ING SH!YE (NUT in my works car-park reversed their big-assed 4x4 into my car and then £ooked-off!!!! - Leaving behind two dirty great scatches in my bonet - down to the metal and it's creased :nunu:.........

:idea:.......however, being a "glass half-full" type of guy, that means I can mess around £oooking-up my bonet, knowing I'm gonna need a new one anyway - to see what works best in getting cold air in and hot air out - every clound 'n' all that I s'pose!!
 
When money and job allows im getting some vents put in the bonnet, somewhere near me's just got and evo 6 and i love the look of his bonnet, 2 vents in the middle and a vent over the filter for cold air. Not saying that i want my bonnet to look like thet but defo wanting to get a cold air vent cut in for induction.
I'm probly ging to get slated here but really been looking into a carbon fibre bonnet but cant really find any.
 
Ceramic coating of turbo housing, downpipe and manifold.... that will keep heat out of the engine... not cheap though.

<tuffty/>
 
So how much would that cost then and who does it?
 
Bill at Badger 5 can get it arranged, no idea who he uses but he did Mat20vt's A3 conversion and ceramic coated the mani and DP.

Here is another place http://www.zircotec.com/page/-_performance_colours/47

No idea cost wise but I suspect it isn't cheap. I may look into it when I get my 3" DP made up by Bill but an alternative is using that fibreglass exhaust wrap stuff but it isn't the best stuff in the world to work with.

<tuffty/>
 
Oow whens bill doing your DP paul?
Ive looked at heat wrap but never had much experience with it so dont know whats good or not?
 
Incidently, my boss had the reg number SHY 19S on a few different cars, he sold it with his old range rover years ago....Today amazing fact !!
 
You can always drill speed holes ala hommer simpson!!!!

adidasboy - did you see the 4x4? any cameras in the area? I HATE 4x4 drivers [well not all of them, I am sure there are at least 5 that I will meet one day that I wont hate]
 
Why not leave the bonnet alone and sort out your coolant and get an oil cooler?:cold:
 
Oil coolers is an interesting one, but got no where to put it.. got a front mount in the way.. where else do people put them..? maybe behind the top vent... the only slats, vents i would ever get is the 4 slits in the wing, subtle and effective, only problem is the A3/S3's are very round cars, the slats are abit square..
 
you can also get zinc plateing on dps works just aswell realy and half the price of ceramic use it on a mk2 escort coswort were doing at the moment, plus having a freind who dose it aswell also helps:yum:
 
this is actually something which has been bothering me too.

After getting my turbo replaced I want to make sure everything is ok. Ive never had a car which has run such a temp under the bonnet as my S3 even my mrs's old cupra never felt as bad.

Not sure about the louvre thing tho.

Would a mesh grille make any difference?
 
if you get louvres, you will need to make sure that any water that runs in through them doesn't drip onto anything electrical.
 
Getting cool air into the engine bay isn't the issue I don't think, its getting the hot air out. I have found that opening the bonnet for a 10 mins or so after a run drastically reduces the heatsoak under the bonnet but obviously its not a practical solution.

Methods for getting heat out of the engine bay is always going to be a compromise between practicality and looking ridiculous. If you can prevent heat generation in the first place thats gotta to be a start... hence ceramic coating...

<tuffty/>
 
Thats the only concern i have regarding vents, water, how do the evo boys etc prevent water in the engine, electrics etc?
 
Thats the only concern i have regarding vents, water, how do the evo boys etc prevent water in the engine, electrics etc?


Drip trays.

If you look at an Evo's bonnet then you're hard pushed to see andy actual 'engine' through them.
 
and what about removing the fog light?

Just the one????

But seriously.... only thing removing foglights 'MAY' achieve is increased airflow to the SMIC's which once a car is mapped are inefficient anyway.

You could also consider spacing the bonnet hinges race car style. Raises the rear of the bonnet allowing hot air to vent out.

<tuffty/>
 
Remove all the plastic cowling around the wipers and bulkhead, and then the undertray.

Makes the underbonnet less stuffy.
 
the louvres work by sucking out the hot air dont they, not letting in cold air?, unless its raised and facing forward, if its just cut out in the bonnet im sure the hot air would be sucked out.
 
None of this is really necessary in a 1.8T... You won't really gain anything trying to cool it down a bit unless you put on a big *** scooby style vent at the back above the turbo and manifold...but then it would look hideous.

Best you could do if you think you need to is get some ducting hose and feed some through the the back of the engine bay at the turbo.
 
I looked into cool louves on my last car and iirc its an expensive job with having to supply a bonnet, ship it, press it, paint it etc.

Am I missing something or is there a reason why you need to let the car cool down quickly ? If its been ok for the last few years it can't make much difference now?

As someone suggested you could get some bonnet raisers and lift the back end RS Turbo stylee :o.k::laugh:
 
you could change the coolant temp sensor and get some kenlow fans or uprated ones?
 
That's funny Dani, I to was looking at CF bits n bobs (mainly bonet and wing mirrors) last night - but it's just sooooo fooooking expensive!!

Air in / out of the engine bay through louvres, slots vents (whatever you want to call them - NOT scoops) I think depends mostly on the angles that they're cut into the bonet / wing - think of it like a desk fan or an aeroplane / boat propellor, the angle determines the direction of air flow.


Bruce - I hear ya buddy - fooooking tw@ts!!! - they probably didn't even realise - (NUT!!
 
The cool Louvres will create a vacuum and the cold air will go through the front grill as normal but force the hot air out the louvre. It wont be too expensive to get a bonnet louvred if you can visit their workshop in Hampshire because they can do it while you wait. £5 a louvre up to 20 then £2 each there after but you shouldn't need more than about 10 (£50), then get your bonnet resprayed. I could get the bodyshop i use to spray a bonnet for under £100.

Too be honest as said above it wont make too much difference because there are members running 350bhp BT kits who dont need them.
 
I disagree, unless you have a wind tunnel and can accurately place them, they will not necessarily create a vacuum, or force air out.
They will let hot air escape, but in order for it to be assisted in any way, they have to be placed strategically. As full as the engine bay is already, I can see air being forced out the top in any way. It could be all for nothing is all you do is create a vortex around the hole [or what ever fancy word you want to give it :rolleyes:] which could possibly trap air their any way.
Wouldn't mind seeing a write up with temp reading before and after, but it really would be a shot in the dark.
 
itll more likely cause a vacum when put on the side, as you said, the bonnets angled, but if the air goes cleanly over the louvres then it will cause a vacum, better at the back closer to the middle of the bonnet, then cold air will deplace the hot air.

its different but i saw an aeroplane with one window taken off, they filled the aeroplane with smoke and put it in a massive wind tunnel, the air rushing past the window sucked the smoke out. i think an aeroplane would have more vortexs than a car.
 
.......Wouldn't mind seeing a write up with temp reading before and after, but it really would be a shot in the dark.

That's what i was thinking - seeing how mine is now shagged - I thought I could have a "little play". Thing is, I'd prefer to do a 'before & after' temps test during the summer, but knowing what I've got planned over the next couple of months, I'm not sure if I can really afford it - knowing my luck, I'd cut a load of holes here, there & everywhere and then go light in the wallet - leaving me to drive round in a slab of edam for a couple of months!!!

As someone said in another thread, one concern using heat tapes on and around the turbo would be the turbo itself then not being able to release the heat build-up.

@Rich, think I asked in another thread, but I'll ask again anyway!! - how did you get on with that cone filter mounted into the standard air-box that you was doing a few years back - notice any benefits?
 

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