Thread: Exhaust Heat Wrap, how hot & how much

Originally Posted by AndyG

Am looking at wrapping the exhaust to reduce heat next to transmission and my leg: ( Defender)
Starting from the first join from the manifold, what's the likely max temperature in this area. I see tapes go up to 1500 C, but that must be for manifolds/ turbos on performance vehicles. 500 C should be enough for the next section?, or 850 C ?
By my calcs, invoking the 200 mm circumference and 100% overlap, then i should get 2.5 m wrap out of 20 m tape ?
Finally thinking of removing these sections of pipe to wrap them, this will be a first for me. How hard ?
thanks Andrew

I was going to do the same after doing a bit of reading on here went to a real exhaust shop not the local Franchise types asked about Wrapping they suggested ceramic coating rather than Wrapping so off i go to it to the place they recommend (can't recall name ATM) that's the way i'm going now but will wait till after Winter is over coz ATM i'm still needing the zircon on all the time to stay cool in the box & figured the heat will be welcomed in mid Winter.
If u think this is the way u'll go too then PM me & i'll look for the card & FWD details to ya.

Not sure what engine you've got, but I'd say 850deg would be higher than a turbo-diesel would normally get.

I've never got around to doing the one on my county (wrap is still sitting on the shelf), but one tip I did pick up was to wrap from the rear towards the front as the overlaps are facing away from the direction of airflow/mud etc.

Steve

Ceramic coatings are to make things pretty. There is no insulation value.

Post turbo you won't see more than about 650C unless a complete muppet has tuned your engine.

Originally Posted by Dougal

Ceramic coatings are to make things pretty.

...not if you've got a decent ceramic coating!!!

You can use the zorst wrap stuff but it's horrible to work with and it'll only last for a few years before it falls apart. I'm also not sure how it will cope with the the kind of crud thrown up off-road.

Ceramic coating is a neater option for channeling the heat but can get quite expensive.

FWIW - I've been jumping through these hoops with my TVR as the heat from the manifolds can damage the chassis rails. I looked at the wrap option but discounted it for the above reasons. Instead, I've gone for a thin ceramic coating on the manifolds, to take some of the heat and used gold reflective tape on the chassis to reflect the rest of the heat.

M

Originally Posted by camel_landy

...not if you've got a decent ceramic coating!!!

3mm of ceramic coating might give usable insulation. But I'll bet most coatings are only microns thick.

Thanks all,a good wrap is $100 , will give it a go & consider it a consumable, as I will do things to the exhaust in time.

Originally Posted by AndyG

Thanks all,a good wrap is $100 , will give it a go & consider it a consumable, as I will do things to the exhaust in time.

This is the stuff that was recommended to me, I bought it ages ago but its still sitting in the shed waiting to be fitted.....

TAN Exhaust Heat Wrap Titanium Fibre 30M L X 50mm W 10 X S Steel Zipties | eBay

exhaust wrap (eg the kevlar type) will attract mud, retain water, and can lead to rusting of a mild steel exhaust system. If you've got full stainless, go nuts.
Many factory options use steel pipe with a heat shielding clamshells around them, but this is not easily fabricated at home.

Ceramic coatings can work. its common in racing applications, as its light, prevents heat soak and heat dissipation, and can even assist turbo operation through retaining as much heat energy pre-turbo (more gas volume) for more extracting more boost peer m3 of gas thru the exhaust turbine. Doing a whole exhuast would be cost prohibitive though.

In all honesty, if its just a hot trans tunnel that you are experiencing, then just get a heat shield, mould it to the system, make a few brackets and fix it up. Reflecting back all that radiant heat is probably going to drop temps by half alone.
Somethign like this: http://www.aclperformance.com.au/prod_heatshield.htm