EXHAUST MANIFOLD WRAP

[jwigglesworth]

Simple question- good idea or not?
Haven't got the nice stainless steel ones on mine if this is relevant
Thanks again
Jeremy

[mk1fan]

Been discussed a lot recently.

I have ceramic coated my manifolds. Performance 1 Coatings in Didcot is who I used.

[Oldred_V8S]

Read many alarming things about wrapping causing splits in the manifold.

[GreenV8S]

I think splits are inevitable either way. You have very different lengths of primary pipe solidly connected at both ends with no scope for anything to flex to accommodate thermal expansion. It leads to huge stresses and I think fatigue failures are inevitable. I can't say that thermal wrap or ceramic coating have made this any worse. In fact it's been quite a few years since the last repair, despite very heavy power loadings and ceramic coating. Maybe the bonnet vents have helped by reducing the amount of heat soak, but that's just speculation.

Edited by GreenV8S on Wednesday 27th April 20:54

[AutoAndy]

My uneducated answer from when I thought about it. My answer was, why bother!

[TVRees]

Would the exhaust wrap (i.e. insulation) help to reduce the engine bay temperature a little ?

Since I've got the engine out at the moment, I am tempted to try some wrapping on the exhaust.

[GreenV8S]

TVRees said:

Would the exhaust wrap (i.e. insulation) help to reduce the engine bay temperature a little ?

It did on mine - and I think it reduced the rate of heat-related component failures as a result, although it's hard to be certain. Wrapping is only a temporary fix though since the wrapping will gradually fall apart. Ceramic coating is IMO a better long-term fix if you can manage that.

[Karckso]

mk1fan said:

Been discussed a lot recently.

I have ceramic coated my manifolds. Performance 1 Coatings in Didcot is who I used.

Hi,
I have also used the guys at Performance 1 Coatings www.performance1coatings.com.

Really happy with the job they've done. It's been a while since I've done it and I sold the car in the meanwhile.
I'll see if I can find a photo and post it here.

Cheers

[GreenV8S]

Karckso said:

I have also used the guys at Performance 1 Coatings www.performance1coatings.com.

I did mine myself using Camcoat's Black Satin ceramic paint. It saved a lot of money and is fine for what I need although I'm sure a professionally applied coating would be better. I only coated the outside, which means the coating stops heat escaping from the outside of the exhaust but doesn't stop heat from the exhaust gas from heating up the metal. This means the engine bay is cooler but the metal of the manifold is probably hotter. Some of the benefits that performance1coatings describe would only apply if the inside was coated too so the actual manifold was cooler, although their site suggests they only see internal coating as optional. Did they coat the inside on yours, or discuss that as an option?

[Karckso]

Hi GreenV8S,

Yes, I've asked the same questions!

The internal coating comes as an add-on only. They charge £50 on top of the outside coating.

What they've told me is that, besides the coating being thin, if you coat the inside, you're reducing the gas area and creating more pressure.
also, that the environment inside the pipes are very harsh and that no one can control it, so it isn't very advisable.

In the end, I went with their advice and I'm happy with it.

Cheers,
Karckso

[DamianS3]

In performance terms the wrap / coating is to keep the manifold hot. This promotes faster exhaust gas exit iirc.. While also helping with under bonnet temps.

Damian S3

[GreenV8S]

Karckso said:

if you coat the inside, you're reducing the gas area and creating more pressure

With due respect to the specialists saying that, it sounds like total b*ll*cks. I think the reality is that they know it's much harder to coat the inside, and they don't want to do it, but want to pretend that it's possible so that they can continue to claim the benefits from it in their advertising.