Engine Bay Heat!!!

[Alpineandy]

Engine Bay heat is a real problem for rear engined cars, as we all know
.
I'm fed-up with having the alternator rebuilt on my Yellow A310 and am now trying to work out a cure.

I hear that exhaust bandage isn't a good idea as it maked the exhaust manifold rust quicker than a late 70s lancia, and seems to knock out the silencer boxes.

Has anyone tried these 'exhaust manifold blankets'?
Do they do the same thing?

Any other ideas?

[simontaylor]

How about a home made heat shield to keep the worst of the manafold heat off and a bit of ducting to bring cool air from under the car on to the alternator. ????

[Alpineandy]

From some ally ducting I've made a heat shield on top of the section that runs directly under the alternator, which has a mild effect, and I'm trying to get hold of a couple of meters fo 1&3/4 or 2 inch heat resistant ducting to run air from the 'ear' air intake (which was missing when I bought the car) but I can't find anywhere local.
The air duct should make some difference (it does on the red one) but the time when it isn't very effective is stuck in traffic, when there's no air being forced in. So I'm hopeing you clever guys know a trick or two and will past it on.

Ive used exhaust wrap a lot in the past (its so good you can put your hand directly on to it) but on more modern alumiumised systems or stainless which are less prone to rusting. I take it your system is plain mild steel? As long as the system is properly re painted all over then wrapped then you won't get a problem. I find the problem is more common on front engined transverse cars where the manifold is at the front, more direct to the elements, dont know how this fairs on an Alpine.

[Alpineandy]

Thanks for your imput Mr G.
A number of people have said that's the way to do it, But I've also heard many advise not to use wrap on anything other than a race car.
There are various reasons (some discussed at: http://www.clubcobra.com/t47158.html )
So I was hoping for some alternatives.
Ceramic coating sound expensive, What about a can of Radiator enamel down the inside of the pipes..... OK I'm grasping at cheap straws here.

[simontaylor]

What about just keeping an eye out for a replacement manifold for when the original rusts through?
Or, self insurance: Just keep your car keys next to a jar. Every time you touch the car keys, put a pound in the jar. You will hardly notice the cost but you should have a good deposit for when you need to spend money on the car, like a manifold or an alternator.

I can see on the Cobra forum what theyre getting at. Theres a cheap market for steel headers for Yank V8s, but when you make an aftermarket manifold it has to be well supported or it will crack under severe heat. Andy, have you aftermarket manifolds or originals? Their statement of there being too much heat is rubbish. The old Renault F1 had wrapped manifolds and these were turbo!, the manifolds would glow, and modern rally cars today, all have wrapped mandrel bent manifolds, again with alot higher temps than a n/a V8. Keeping heat in your manifolds speeds up gas flow and aids combustion. If youve got the standard cast manifolds then youll be ok, if they are aftermarket, you may want some bracing applied across the primarys to minimise any movement or flexing.

[Alpineandy]

. The old Renault F1 had wrapped manifolds and these were turbo!, the manifolds would glow, and modern rally cars today, all have wrapped mandrel bent manifolds, again with alot higher temps than a n/a V8.
If youve got the standard cast manifolds then youll be ok, if they are aftermarket, you may want some bracing applied across the primarys to minimise any movement or flexing.

David,

The manifold and system is devil (I believe).

The F1 and rally cars systems are replaced regularly (for F1 almost - Daily).

I may decide that the best option is indeed to clean up, paint and wrap the manifolds, But I'm really looking to find out as many alternatives as possible. I don't have the spare cash for Stainless at the moment (probably not for a couple of years minimum) so I don't want to dive into wrapping and for it to rust through in 6 months, so your advices about cleaning/painting is already a big benefit.

I also vaguely remember that there was some special paint (resin like) to go over the wrap which sealed it from water etc. Anyone know if that's still available.

Anyone actually had their exhaust ceramic coated, any good and how much?

If I do 'wrap' the next question will be 'how can I get rid of the heat from the exhaust box', Any Ideas?

[pgoldsmith]

I know yours is a 310 but with GTAs they have a circulation fan and extraction fan for the turbo. Could you not in some way use a fan to pipe air in around the engine and alternator? Correct me if I'm wrong but with GTAs for the Swiss (and Germans I believe) they have their fans running constantly at 6v when a temp of 60 degrees is reach and then converts to 12v if 90 degrees is hit. If you could fit a circulation fan in place with ducting and set it at a 6v it may provide just enough cooling air to help?

[Alpineandy]

I'll have to have a good think on this one, It sounds like a cunning plan.