Temp control under the bonnet.

[Steve Webb]

Is anyone using a thermal wrap on the Turbo or any other methods for trying to keep the temp down under the bonnet?
I know a lot of the Integrale boys like to partition off the air filter area to ensure that the engine draws in cold air, but has anyone done anything similar for the Q4 and if so have you seen a difference?
Same goes for the turbo wrap as well, although I'm not a big fan of thermal wraps as they can trap moisture and increase corrosion.

Steve

[jimnielsen]

Steve, I think that the turbo blanket things that you can get are great - they keep the heat in the turbo - not the engine bay. But they are expensive...much better than any 'wrap'. Ceramic coating works great for the headers/extractors - but its really only practical with stainless steel exhausts - and its also expensive.. also much better than any wrap!

I also have a heat shield between the headers and the fan...


http://www.driftworks.com/forum/parts-sale-private-sales/83964-garrett-turbo-blanket.html

jim.

[wrinx]

I'm not a fan of wraps either, they break down fairly quickly and, as you say, cause corrosion :?

Have you thought about ceramic coating for the manifold?

Bonnet vents... :lol:

Edit: No idea about the turbo wrap....surely dissipating heat from the turbo is a good idea???

wrinx

[Steve Webb]

If I were to be getting a new manifold I'd get it coated for sure. I guess from a reliability point of view taking the heat away from the turbo would be best to stop the oil in the turbo from coking up. But from a power point of view keeping the gasses as hot as possible and therefore as expanded as possible is best until they leave the turbo, then cool them down so they take up less space in the exhaust.

As for bonnet vents, not keen on letting rainwater in at the top of the engine, and I'm not convinced about how effective they are. The bonnet tends to be a high pressure area as the air is squashed as it tries to get over the car, so might not allow as much of the hot engine bay air out as you think it would.
The often quoted example of this is the Nissan Sunny GTiR rally car, slightly different set of circumstances as the intercooler for the engine is mounted on top of the motor.
They found that when running in night stages with a lightpod on the bonnet they got a performance boost as the pod created a low pressure spot over the bonnet vent increasing air flow over the intercooler. As a result they ran the car with the light pod even in the daylight.

[Suzumushi]

I'm not a fan of wraps either, they break down fairly quickly and, as you say, cause corrosion :?

Have you thought about ceramic coating for the manifold?


wrinx

I've got ceramic coated mainfold and guess what happend today
damping mat under the bonnet directly above mainfold started to burn
a lot of fire and smoke,
fortunately had fire extinguisher and sorted this out very quickly, almost no damages under the bonnet exept the mat.

so ceramic coated is for sure not enough... or damping mat was really in bad condition,
what do you think about this?
how to protect better engine bay and keep away heat
wrap on mainfold? turbo wrap?
anyone using above setups ?

best regards

[Steve Webb]

Do you mean the sound deadening mat that is fastened to the underside of the bonnet?
I've never heard of that catching fire before, but I've removed mine just in case. What manifold do you have?

I'm not a fan of manifold wraps as they can hold moisture and cause accelerated corrosion.

I've thought in the past that it would be a good idea to have a central vent in the bonnet, similar to the integrale to allow some of the hot air above the Turbo/manifold to exit the engine bay.

[mpampis_]

You can remove two sponge (left-right) and the engine area will refresh with cold air

[1NRO]

Just make gold shields for the space between what gets hot and what doesn't want to be :D

[AlfaJack]

Just make gold shields for the space between what gets hot and what doesn't want to be :D


Like a McLaren F1 :driving-014:

[Steve Webb]

Also goes to show how important it is to have a fire extinguisher in the car. I always make sure I've got one to hand.

[Suzumushi]

Do you mean the sound deadening mat that is fastened to the underside of the bonnet?
I've never heard of that catching fire before, but I've removed mine just in case. What manifold do you have?


took some pictures
http://i44.tinypic.com/t7omq1.jpg

take it out away

http://i44.tinypic.com/20hwv84.jpg

zoom

http://i43.tinypic.com/2akcvg9.jpg

cooked bonnet (or especially for my friend hood)

http://i39.tinypic.com/ncdxme.jpg

ceramic coated stainless steel mainfold

http://i40.tinypic.com/2yozi3q.jpg

and cleaned bonnet(hood) - not too much damage at all - luck

http://i41.tinypic.com/m78adj.jpg

of course i have checked tooday in same conditions and the bonnet is now very very hot :), so it must be protected somehow
i've ordered aluminium matt to replace the old one, hope it will help for now.


Also goes to show how important it is to have a fire extinguisher in the car. I always make sure I've got one to hand.

it's required by the law in Poland to have one in car, otherwise you will not pass the yearly MOT.

regards

[wrinx]

Lucky escape!

I always carry an extinguisher in the Q4....can't think why :lol:

wrinx

[Juan AR155Q4]

Sorry, but I don?t think that wraps will hold moisture, not if the car is periodically run (please, no jokes with Q4+peridically+runing)

[Steve Webb]

Very true Juan, but in the UK and other parts of Europe, the climate means that the engine bay gets damp even without the car moving, if the manifold is wrapped, the wrap will absorb the moisture and keep it damp even after the rest of the engine bay has dried out.

Oh and Suzu, if you remove the two foam parts that are pointed out in the pic below, it should help airflow through the engine bay.


http://www.berlinasportivo.com/forumpics/underbonnet.jpg

[Xti]

Lucky escape!

I always carry an extinguisher in the Q4....can't think why :lol:

wrinx

It's understandable and it's safe, Wrinx.
I have a strange feeling too when thinking at electric part. I don't like surprises.

Also, when my Q4 remains in garage for few days or more I use to disconnect the battery. Is this allright with the electrics (ECU, etc..) ?? Thank you!

Cheers,
C.

[Brul(tm)]

took some pictures
http://i44.tinypic.com/t7omq1.jpg

take it out away

http://i44.tinypic.com/20hwv84.jpg

zoom

http://i43.tinypic.com/2akcvg9.jpg


That looks very familiar.
I hhave had the same problem with the isolation under the bonnet.
Though it looked very nice in the dark when it happend :biggrin:
Also very very hot..... :redface:

[Suzumushi]

Oh and Suzu, if you remove the two foam parts that are pointed out in the pic below, it should help airflow through the engine bay.



Thanks Steve for an idea, done it already and some temporary solution to protect hood below.

http://i41.tinypic.com/dxlidv.jpg

and in the near future i want to make some vents in the bonnet, but first i will get spare one for cutting and welding tests :)


<edit>
some interesting infrared photos

http://i43.tinypic.com/1zlavz9.jpg
http://i39.tinypic.com/4ruuyv.jpg
http://i42.tinypic.com/scfe3k.jpg
http://i39.tinypic.com/ymb1s.jpg
http://i41.tinypic.com/e0hauw.jpg
http://i41.tinypic.com/invnko.jpg


regards

[Steve Webb]

Were those thermal images taken after you had been out driving the car?

Its interesting to see on the shots of the bonnet how hot the area just above the plenum is. Looks like it is nicely warming the air that has just been cooled by the intercooler.