Exhaust Wrapping - does it make much of a difference to performance?

[JAL73]

I have a factory standard 420R and am considering having this done.

It doesn’t seem like a very expensive upgrade but wondering whether any others on here have had this done and noticed any difference in performance, sound or reduction in heat ingress into cabin etc.

I understand the main logic is to reduce air temp in the engine bay which might have favourable impact on air density going into throttle body and hence some incremental power gains but no idea if you would notice this or if its worth the hassle. 

[Jonathan Kay]

Discussion from 2018.

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Jonathan

Edited November 23, 2023 by Jonathan Kay

[JAL73]

Thanks Jonathan, reading these threads it seems that nobody is claiming any noticeable performance benefits.

The main positive is that it seems to prevent heat damage to starter motors and wires and keeps footwells a bit cooler but my 420 doesn’t really seem to suffer either of those problems (IMHO) so not sure its worth the bother, especially as there are concerns about resultant excessive heat transfer to other engine/ exhaust components upstream and downstream of the manifold. 

You would think that if exhausts wraps were that effective then they would be offered as factory fitted options I suppose.

Edited November 23, 2023 by JAL73

[Colin_T]

As an alternative to exhaust wrap…. I recently had mine ceramic coated with cerakote . Decided to go for a more natural looking burnt bronze colour, rather than something too silver/blingy.

it was previously wrapped around the manifold and collector. But the radiant heat caused some localised damage to the PPF as the system passes through the body.

since done plenty of sitting in traffic and two trackdays and no further PPF damage so seems to work well.

I think it’s a neater solution to wrapping too as after time they always end up looking tatty.

I had this done by a company reasonably local to me in Essex. Cost was £320 incl vat which included them doing all the blasting and prep work too. 

Food for thought 

 

Colin 

[PlastererPete]

I used a DEI exhaust wrap “sock” (for want of a better phrase) on my CSR. It certainly helped the footwell temps for me, which was the main issue I was having during summer driving. It also meant I didn’t have to take the headers/manifold off, just the collector and silencer. 

[Wrightpayne]

I have a K series which is wrapped mainly to stop the heat killing the starter motor!

[JAL73]

14 hours ago, Colin_T said:

As an alternative to exhaust wrap…. I recently had mine ceramic coated with cerakote . Decided to go for a more natural looking burnt bronze colour, rather than something too silver/blingy.

it was previously wrapped around the manifold and collector. But the radiant heat caused some localised damage to the PPF as the system passes through the body.

since done plenty of sitting in traffic and two trackdays and no further PPF damage so seems to work well.

I think it’s a neater solution to wrapping too as after time they always end up looking tatty.

I had this done by a company reasonably local to me in Essex. Cost was £320 incl vat which included them doing all the blasting and prep work too. 

Food for thought 

 

Colin 

I’ve heard with ceramic coating they coat the inside as well as outside, is that correct? Did you notice any performance gains with the ceramic coating? 

[Colin_T]

6 minutes ago, JAL73 said:

I’ve heard with ceramic coating they coat the inside as well as outside, is that correct? Did you notice any performance gains with the ceramic coating? 

This particular stuff gets applied from a spray gun, so anything inside would only be from overspray or anywhere left unmasked. 

Could feel no difference performance wise before or after with my ass dyno. 
 

my reasons for doing it were primarily to stop damage to the PPF and to make it look better. 

[TomB]

I've run wrap on my K series for at least a decade after loads of starter problems and crusty cables.  No ill effects on the engine so far, but its 'only' a 1.8 Supersport, nothing too lary.  Performance-wise, nothing discernible this far from fitting it, but I remember its did change the tendency for exhaust pops so it was doing something.      

[Wayne Stambaugh]

I’m in the US but we have a company here that puts on a true ceramic coating used primarily in racing. It isn’t the prettiest finish and it doesn’t get better with handling and age but if you really want a performance benefit this is a good one. The name of the company is Swain Tech Coatings. They are located in New York state. You have to send them your exhause parts for coating, you can’t do it yourself. I have had a couple systems done with it and it definitely keeps the heat down in the engine bay and under the car. As for a notice in performance, I think you would probably have to put your car on a dyno to find out. The theory is that it  speeds up the exhaust flow in the pipes and evacuates the the exhaust system more quickly so there is less resistance of gases coming out of the head.  Look up White Lightning exhaust coating on the web address below.

Swaintech.com

[StevehS3]

Interesting topic. Does the actual engine itself get hotter (due to the lack of heat dissipation) or is it cooler by insulating the headers?
Even with a well insulated engine bay I am surprised by how much heat comes into the cockpit. It’s a bit much in the summer but I am glad of it in the winter! 

[John Vine]

I wrapped my R400D primaries with the sole aim of reducing cockpit temps. It certainly did that (assisted by tunnel insulation) but I couldn't detect any change in performance.

JV

[SLR No.77]

I cannot advise one way or the other but only state my experience with wrap which does appear at odds with everyone else …

I wrapped the primaries on my tuned SLR, so a higher powered K, from the head flanges to just inside where the primaries exit the chassis.

Later when I had the cam pulleys off for a belt change I noticed that the brass ferrule moulded into the rear section of the pulley cover (behind the exhaust cam) had actually melted the surrounding plastic. I subsequently unwrapped the primaries and have not experienced the same again.

It’s only one experience but I do think wrapping causes more heat to be retained in the head.

Stu.

[aerobod - near CYYC]

Bearing in mind that you are generating of the order of 100kW of continuous heat from the engine when it is being used for spirited driving (such as on track), exhaust wrapping will just redistribute where that heat is being dissipated from. I can see Stu’s point that in some circumstances the amount that has to be dissipated from the head may increase if less heat is radiated from the headers.

[Ainsley]

As its an insulated wrapper, it probably does reduce the temp in the engine bay, but also I thought it allowed the catalyser to run hotter, thereby making that work better, especially important for your MOT.

[Golf Juliet Tango]

Quote

wrapping causes more heat to be retained in the head.

The heat has to go somewhere, Newton told me that. I'm sure hotter gas goes to the catalytic converter (if fitted) &/or the silencer; that some is returned (or retained) in the head and block is to be expected. 

[BigCol]

9 minutes ago, Golf Juliet Tango said:

The heat has to go somewhere, Newton told me that.

I’m confident you’ve a few years on me, Stephen, but I didn’t realise Sir Isaac was a contemporary of yours! 🤔😳🤣🤣🤣

[Golf Juliet Tango]

Me & Isaac:-  bros 😋

Edited November 26, 2023 by Golf Juliet Tango

[Ainsley]

Any heat in the head should be taken care of by the cooling system, so that should not be an issue.

[Drumster]

I’ve had wrapped primaries on both my x/flow and Zetec engined 7 (therefore no cat required) for 12 and 13 years respectively and other than reducing the heat in the engine bay and passenger footwell I’ve not experienced any other pros or cons.

[Jonathan Kay]

Newton never got to conservation of energy, although a contemporary did.

Heat as motion has an ancient history. But no-one got to heat as energy for nearly another century.

Jonathan