Heat wrap or shielding a 10 valve manifold?

[Gaz]

my inlet manifold gets very hot.. what with it being directly above the exhaust manifold.

I'd really like to try and shield it some how.

Has anyone had experience with using Heat wrap on a KV?

I did once try making a heat shield between the two manifolds out of some old aluminum I had laying around. It was a bit unsightly tho so i chucked it.

Is a lot of the heat soak coming off the exhaust? or is it being transfered direct from the actual head its self ?

[4v6]

One way to reduce the heat transfer is by using a Phenolic spacer between the head and the intake to cut down on direct metal to metal conduction.
The air to air surface radiation can be reduced by a shield.
I made a very similar item to fit on the golf as the turbochargers in fairly close proximity to the intake.

In my case i used two thin sheets of stainless with a layer of thermal wrap/blanket sandwiched between and bolted to the inlet by the fixing bolts.

Certainly helps to keep it cooler.

[Isimmo]

When the vehicle is in motion, heat build-up between the inlet and exhaust will be pretty minimal due to the substantial airflow between the inlet and exhaust manifolds. Stationary, the old girl will transfer heat from the exhaust to the inlet, which is why WR quattros have the injector cooling fan - this is to help prevent fuel evaporation in the injectors (and subsequent poor hot starting) after the engine is shut down. Audi didn't consider a similar system was necessary for a KV and to be fair, I can understand why.

The heat from the exhaust side originates in the chamber, passing into the head before reaching the manifold, so heat soak back into an alloy head from an iron block is going to negligible as the head is bolted to the heat source.

I'd suggest, on a KV engine, you'll just be wasting your time with no or negligible change in the heat transfer.

[4v6]

You have the problem of radiant heat transfer Ian, thatll heat the intake up regardless of the airflowing past as its got line of sight to the hot exhaust.
Id suggest if you placed a temperature probe on the surface of the intake in proximity to exhaust manifold, youd see some very high temperatures being transmitted.
The airflowing over the two parts will obviously transfer some heat away as the intake absorbs it but when you have line of sight in such close proximity that effects going to be small in comparison to the temperatures transmitted.

Itd be a bit like grilling your toast and blowing cold air over it- the toast still gets done due to the radiant heat.

The other heat issue is the exhaust gases as they travel through the ports and heat the surrounding material, which is transmitted to the intake via conduction.

Anything you can do to drop intake temps will show up in cooler charge temps, which means you get a denser charge and a bigger bang for the buck.
At the end of the day, experimentations going to determine a win or lose situation on this question i think .

[20vcqdriver]

Heatwrap worked brilliantly on my 7A exhaust (see attached). Keeping the exhaust wrapped up also speeds up airflow through the Exh manifold as the exiting air is not getting cooled as quickly by the manifold as it exits the engine and therefore turbulance is reduced. Doubt it makes a masive diference but every bit helps.

[4v6]

Originally Posted by 20vcqdriver

Heatwrap worked brilliantly on my 7A exhaust (see attached). Keeping the exhaust wrapped up also speeds up airflow through the Exh manifold as the exiting air is not getting cooled as quickly by the manifold as it exits the engine and therefore turbulance is reduced. Doubt it makes a masive diference but every bit helps.

Ha! Nice job there, must have taken a few hours of winding to get that lot in situ!

[Gaz]

Originally Posted by 20vcqdriver

Heatwrap worked brilliantly on my 7A exhaust (see attached). Keeping the exhaust wrapped up also speeds up airflow through the Exh manifold as the exiting air is not getting cooled as quickly by the manifold as it exits the engine and therefore turbulance is reduced. Doubt it makes a masive diference but every bit helps.

what make/brand wrap did you use ?

I was just a bit worried if there would be any chance of over heating the manifold, that it might crack??

One of my m8s has a 2.0L escort and an heat wrapped Ashley manifold, but hes had to wield it a few times cause of cracking. I think he read somewhere later that it wasn't recommended to heat wrap an Ashley mani. & He has vowed he will never buy an Ashly fanymold again! lol

[Isimmo]

Originally Posted by Gaz

what make/brand wrap did you use ?

I was just a bit worried if there would be any chance of over heating the manifold, that it might crack??

One of my m8s has a 2.0L escort and an heat wrapped Ashley manifold, but hes had to wield it a few times cause of cracking. I think he read somewhere later that it wasn't recommended to heat wrap an Ashley mani. & He has vowed he will never buy an Ashly fanymold again! lol

You won't be able to wrap a standard Coupe Quattro manifold, the cast shape will prevent this.... If you wrap it up, It'll look like a flattened Christmas turkey...

[Gaz]

Originally Posted by Isimmo

When the vehicle is in motion, heat build-up between the inlet and exhaust will be pretty minimal due to the substantial airflow between the inlet and exhaust manifolds. Stationary, the old girl will transfer heat from the exhaust to the inlet, which is why WR quattros have the injector cooling fan - this is to help prevent fuel evaporation in the injectors (and subsequent poor hot starting) after the engine is shut down. Audi didn't consider a similar system was necessary for a KV and to be fair, I can understand why.

You know, i'm sure i've seen quite a few 10 valve non turbos with the injector cooler?

[Gaz]

Originally Posted by 4v6

One way to reduce the heat transfer is by using a Phenolic spacer between the head and the intake to cut down on direct metal to metal conduction.
The air to air surface radiation can be reduced by a shield.
I made a very similar item to fit on the golf as the turbochargers in fairly close proximity to the intake.

In my case i used two thin sheets of stainless with a layer of thermal wrap/blanket sandwiched between and bolted to the inlet by the fixing bolts.

Certainly helps to keep it cooler.

Where would i find a 'Phenolic spacer' ??