Board logo

exhaust wrap
r1_pete - 26/9/08 at 08:28 AM

What are folk on here's view on exhaust wrap, there are many contadictory stories about, views and experiences good and bad welcome.

I'm considering it as my manifold has to run quite close to the bodywork and Starter Motor Rescued attachment myexhaust.jpg
Rescued attachment myexhaust.jpg

Mr Whippy - 26/9/08 at 08:42 AM

I'd love to hear of any valid downsides (folk always come out with crazy reasons not to), I love the stuff. Keeps the mud and water off, heat where is meant be and stops you engine bay cooking, especially things like your very close starter

David Jenkins - 26/9/08 at 08:59 AM

Scared the life out of me the first time I ran the car any distance - driving up the road, started to see (and smell) smoke coming out from under the bonnet! Whipped off the bonnet to find the exhaust wrap cooking nicely - it stopped smoking shortly afterwards...

Plus points:
Helps to keep things cool under the bonnet.
Stops you burning your hands when working on the engine.
Supposed to make your exhaust more efficient by keeping the gas moving (not convinced that you'd notice)

Downsides:
I noticed some rust on the manifold when I removed the wrap - I guess it can hold moisture.
The bit of exhaust outside the bodywork gets even hotter than it already is.
Allegedly, it can cause cast manifolds to crack (not a problem for you).

Also, handling the stuff is a bit unpleasant - rather like glass-fibre loft insulation. Made my hands itch, and I could see particles in the air as I worked. Some varieties require a coat of heat-resistant paint when the wrapping is finished. Also, some go on dry, while others go on damp.

[Edited on 26/9/08 by David Jenkins]

bimbleuk - 26/9/08 at 09:21 AM

I've seen cast manifolds crack when using wrap so consider shields instead. I've not had a tubular manifold fail on me but they will fail at a weak/poor weld.

My last manifold was wrapped but at the mo I'm using 2 layer heat shield from Merlin currently and lots of venting on the engine bay. I'm not after every last HP via scavenging for example on my current setup.

I'd certainly consider wrapping on your setup above due to the proximity of the engine mount at least.

[Edited on 26-9-08 by bimbleuk]

nick205 - 26/9/08 at 09:22 AM

The main benefit I see is that it protects other things in close proximity to the manifold - wiring, pipework, starter, alternator etc. I'd suggest you could simply wrap all 4 pipes in one down to the collector and down pipe rather than faffing about wrapping each branch. I also found that stainless jubilee clips worked best to secure it in place. The stainless cable tie items just didn't work for me!

It's pretty cheap to buy (eBay) and IMHO looks good too

As above, I'm not convinced you'd ever notice any improvement in performance on the move - assuming you cooling system is working properly in the first place.

02GF74 - 26/9/08 at 12:35 PM

quote:
Originally posted by bimbleuk
I've seen cast manifolds crack when using wrap so consider shields instead. I've not had a tubular manifold fail on me but they will fail at a weak/poor weld.



Good - you have provided proof for what the sellers of this stuff say - which is that it should not to be used on cast iron manifolds.

The downside usually quoted is that they trap moisture so will corrode mild steel tubular manfilods quicker.


As ^^^ sya, ebay has loads, in different colours too. There are special clips for fitting it that are less jagged than jubilee clips.

BenB - 26/9/08 at 03:06 PM

One of the downsides is that downstream of the insulated part can get too hot. e.g. if you insulate the part up until the pipes go through the bodywork the bodywork is going to get seriously hot!!!
I had heard that you over-heat a cat converter but to be honest I think that might be rubbish- some cars have primary cats pretty much immediately after the exhaust manifold...