Hi all. I saw a thread on here a cuple of weeks ago asking people about the pro's and cons of heat wrapping your exhaust manifold but i never read it and now i carnt bloody find it! Haha, anyway what are the pro's and con's of heat wrapping? Will it alter the 'raspyness' of my exhaust?

Cheers everyone Jonny

Bump, does anyone know??

Helps prevent melting your hand to the down pipe when you stick you hand in there without thinking after its been running

Can't imagine it would change the sound at all. Less heat in the bay is a good thing if you've got bike carbs like me and you don't have a cold air feed.

It probably would change the sound a little bit but you may not notice.

The idea behind heat wrap is as said above, to keep the heat in.

This does have certain performance advantages but it would probably be minimal. The heat wrap does the job of reducing the energy lost through heat transfer in the exhaust system. The heat transfer takes energy from the gas which in turn slows the velocity down and due to this the pressure is altered.

Now when you wrap your manifold there is less energy lost to heat transfer and therefore more of the energy is available to be dispersed in sound or speed etc.

Therefore, not only will the heat wrap change the pitch of the exhaust note it will also dampen the noise (as it has to travel through the matting).

If for whatever reason I had to have my manifold off or replaced or anything like that I would have it wrapped whilst it was off. It just makes sense.

The only downside to using it would be if VW actually designed the exhaust flow around the expected heat loss through the unwrapped manifold but I severely doubt VW would put that much time and effort into designing a road car exhaust system!!!

I couldn't justify the cost/how shitty wrapping goes...on a polo tbh haha

Some slightly mixed thoughts here :) thanks for the responses!

say that after you drop your phone on a red hot manifold. Lol.

If you get some, stick with the white variety as the coloured lagging loses its colour after a week!

If you do decide to get some there is a little trick I learnt whilst working for a rally team that used it.

If you wet the wrap as you are putting it on and pull it nice and tight once it dries it pulls tighter and due to this will stay on longer and not deteriorate as quickly.

Also using lockwire as you go along every 4inches or so will help keep it in place and nice and tight!

If you do decide to get some there is a little trick I learnt whilst working for a rally team that used it.

If you wet the wrap as you are putting it on and pull it nice and tight once it dries it pulls tighter and due to this will stay on longer and not deteriorate as quickly.

Also using lockwire as you go along every 4inches or so will help keep it in place and nice and tight!

Thanks mate :)