View Full Version : Down pipe ceramic coating

25th January 2004, 20:41
Just bought a new H & S downpipe for the rally car and thinking of having it ceramic coated to cut down on heat to the surrounding areas, so don't have to fit the heat sheilds or should I not bother, any comments guys?

25th January 2004, 20:44
I reckon wrap is better - ceramic coated headers I had radiated more heat than another set wrapped.


Jolly Green Monster
25th January 2004, 21:44
I believe I walked past your car a couple of times on Friday http://bbs.22b.com/ubb/smile.gif

Cage looks good!


25th January 2004, 21:49
heatwrap from rally design inmho.


26th January 2004, 02:49
I used Thermotec thermal wrap for my DP.

Jolly Green Monster
26th January 2004, 09:19
I think I have cooltec exhaust wrap on my downpipe which has worked very well for some 25,000miles or so.


Edited to say it is exhaust wrap

[This message has been edited by Jolly Green Monster (edited 27 January 2004).]

27th January 2004, 01:55
I have used both ceramic coating and exhaust wrap.There are two types of ceramic coating. One is white/cream and may be plasma sprayed. The other is some form of dip process.(Cam Coat, Warrington) Both are effective but expensive.
Exhaust wrap can be cost effective if time is taken to do it properly and the results are similar to ceramic coating. (DEI exhaust wrap from Nimbus)

I note that Prodrive ceramic coat(cream/white) and then exhaust wrap. Might be OK for Prodrive where components have a limitted life of a rally or two but when I tried it, the stainless pipes were destroyed because of the extreme temperatures reached because of heat retention so from now on it is one or the other and proper wrap is my current preference.

27th January 2004, 19:57
Thanks for the info guys,
Ceramic coating looked nice on the WRC car at the Autosport show. A company called Zircotec do the cream one for about 35.00 per foot of pipe. Not so bad on a downpipe but expensive on headers. Downside is if it gets scratched/damaged its hard to repair.
Going to go with a good quality wrap. At least it can be replaced fairly easily.

Don't Lift
22nd February 2004, 00:28
There is another school of thought on this. If you wrap/coat it then the exhaust itself gets effing hot. If you only rap the downpipe then where the next section meets there will be massive heat build up where normally there would not be.

I have seen gearbox oils/bodywork suffering heat damage as a result. The solution would be to wrap the whole exhaust. (Time consuming and expensive).

I appreciate the physics of keeping the exhaust velocities high and suggested increases in power but with a bloomin great turbine in the way the gains in performance are negligible.

I wouldn't bother if I were you. If it was the definite way to go then everybody would be doing it. It isn't.

22nd February 2004, 08:46
Dissagree.. the turbine is not in the way.. you need to get the exhaust gases away from the turbine effectively so that it takes less fumes to spin up the turbine / keep it spinning.. faster the fumes are away from the turbo the faster the exhaust fumes are drawn out of the engine giving more chance for a totally empty cylinder and more room for inlet charge..

I know of more cars with a wrapped downpipe than not!?! so more people are doing it than not imho


22nd February 2004, 08:57
My exhaust system is wrapped from the heads to the turbo, and nd after the turbo to the mid section mounting flange.

I've been running like this for 30k miles or so, no problems on the underside of the car what so ever. In fact I've had the car in the air after a hard drive (looking to see where a knocking noise was coming from) and have been able to touch the centre section without too much worry of getting burnt.

Sure it get's hot, but theres a lot of air under the car cooling it at the same time!

22nd February 2004, 09:17

Good point too mine has done about 20k miles with downpipe wrapped and no problems with regard to gearbox or body work near centre section etc.


Don't Lift
22nd February 2004, 09:32
I would suggest the reason than in your opinion more people have a wrapped dp than not might be the type of people you know. It is highly likely the cars you are referring to are owned by persons frequenting thisd type of BBS?

You also have to bear in mind that as characters you are more likely to modify something than not and the purveyors of such products are banking on that.

Has anybody noticed any improvement? Just because you have not had any problems does not mean it is a beneficial modification does it?

That is my point. It is a waste of money if you want a performance gain. If however you want bling, then coating your exhaust pipe is bling. :cool:

22nd February 2004, 11:11

Main reason I wrapped my down pipe was to ensure the bulk head didin't get hot!

Don't forget that the stock headers, up-pipe and downpipe all have heat shields to keet under bonnet temps down!

It get's damn hot under the bonnet with out any of these....and the plastic undertray would never last ;)

22nd February 2004, 13:17
using a good quality exhaust wrap material reduces under bonet temperatures, keeps the top mount intercooler colder and therefor improves power on an Impreza. It works, i have used this on full WRC spec Escort Cosworth rally cars for years, it makes a big diference when running an agresive ALS strategy in preventing under bonnet fires.

I have also used this on NA V8 race engines and it lowers intake temps for the centrally mounted doundraft carbs or throttle bodies.

It's main benefit is in reducing radiated heat which has knock on efects to power and reliability. You wont find this stuff on F1 engines because they use refective gold heatshields and airflow to achieve the same efects.

As to heating the gearbox if you use this, rubish. There were no diferences in temperature of the gearbox when running with the stock exhaust setup or with a lagged decat downpipe (which i lagged to the joint). The biggest diference to gearbox temp was when i started to use Redline Heavy Shockproof oil, it dropped temperatures significantly and ensured gear selection was always silky smooth when on track rather than tightening up with heat expansion with the OEM spec oils.

22nd February 2004, 15:18
Originally posted by Don't Lift:
Has anybody noticed any improvement? Whilst not a direct performance improvement, wrapping the downpipe changed the frequency (and level) of the exhaust note, such that motorway crusing no longer induced migraines smile.gif

I can now drive to a trackday and concentrate on the driving - thus indirect performance improvement ;)

Don't Lift
22nd February 2004, 17:04
Was referring to Sierras reference gearbox oils. I humbly bow in deference to others' first hand experience with the Impreza! tongue.gif

However, John's comments then concentrate more on competition based applications.

John mentions charge temperatures. Has anybody actually tested charge temps before and after wrapping ensuring similar loads and ambient temperatures? The theory works fine, the practicality is that on a road car it is a pointless performance modification. Stu C however has found a benefit! :cool:

22nd February 2004, 19:50
I have run full GroupA Saphire Cosworth 4x4 with ALS (leading the national forest rally championship) and never had any problems with gearbox oil temps lagged or unlagged. We even bought the Turkish championship winning GroupA Sapphire Cossie 4x4 and that was lagged, it also had transmition and diff coolers to keep the oil temp under control due to the high ambients in Turkey, exhaust temp radiation are not a problem with regards to the gearbox oils.

My road going 350BHP 2WD Sapphire Cossie with 3" system never showed any problems.

I had a charge temp gauge on my STi, lagging the downpipe helped keep charge temps lower in standing traffic, it made very little diference to charge temp once on the move apart from the charge temp not being as high after standing still, so took less time before it was safe to give the car full boost.

22nd February 2004, 19:57
Forgot to add, i lagged the downpipe on my westfield cosworth, this helped keep the bodywork temperature down below melting point and stopped the engine mounts going soft due to heat. It was just part of the whole package of heat control on that car, the most eficient control came via wrapping control cables in silicon tubing and then stainless steel overbraid, followed by a tin foil outer wrap. Then mounting these behind an alluminium shield to act as the initial barrier. The brake master cylinder had asbestos and foil blankets wraped around it. Every little helps. :D

Don't Lift
22nd February 2004, 21:10
I agree with the motorsport applications and your Westie (that was a fun car). The gearbox heat issues I was referring to was with a T5 and 500hp, not 4wd. If you try and counter all angles and comebacks in one post you end up writing an essay!! LOL

In my opinion it is a mod not applicable to road cars. Did I not say that earlier? redface.gif :D tongue.gif

22nd February 2004, 21:44
Well, if you don't wrap replacement aftermarket manifolds, up-pipes and downpipes on a scoob then your going to have to look at other ways of keeping things like the: oil filter, CV boots, steering joint knuckles, turbo oil feed/drain pipes, clutch master cylinder, brake master cylinder and servo etc etc cooled! It's all very tightly packed under there!

taking trout's engine on the dyno as an example, look at the temp differences between the wrapped up-pipe and the unwrapped manifold...

Originally posted by Possum Fink:
Getting hot in here!

Getting hotter!

22nd February 2004, 22:10
My cossie and westfield were road cars, as was my STi5 RA. :confused:

Don't Lift
23rd February 2004, 00:43
Originally posted by johnfelstead:
My cossie and westfield were road cars, as was my STi5 RA. :confused: And only in the westie was it a worthwhile mod. I also will ask you to admit that your westie was not your average modded scooby/evo/cosworth type road car now was it?!!

And just coz your STi5 was a road car does not necessarily make it a worthwhile mod does it? Oh never mind. Brick wall, head, not listening....yawn

P.s. Nice piccies of David's motor but anyone see how white a standard manifold gets? Pretty white. MOD UNNECESSARY ON ROAD CAR............. tongue.gif

23rd February 2004, 01:09
Who are you to say it wasnt a worthwhile mod on my cars? I think I am more qualified to say that than you. No, my westfield wasnt a typical road car, but the problems that encountered were typical of all high power turbocharged cars used on the road.

I have already explained how useful lagging the downpipe on my STi5 was in typical ROAD CONDITIONS where you are sat in standing traffic heat soaking the intercooler, ignoring all the other benefits.

I think you are the person not listening. :rolleyes: Please cut out the attitude, just because people dont agree with your opinion doesnt mean you have to get all arsey about it. tongue.gif redface.gif :rolleyes:

Lateral Performance Ltd
23rd February 2004, 01:41
Don't Lift,

You'll find that most people who post on here, either have, or do monitor air charge, under bonnet, and EGT's, etc'.

The vast majority are road cars, with the occasional track, or drag day.

They are saying that on "OUR" cars, there IS a benefit to wrapping/coating headers that don't have heat shields. It can easily reduce under bonnet temps by 30C !

P.s. Nice piccies of David's motor but anyone see how white a standard manifold gets? Pretty white. MOD UNNECESSARY ON ROAD CAR............. tongue.gif As it's been mentioned, out "standard" manifolds, up pipes, and turbo's are covered in heat shields to stop heat being radiated, and removing these has a detrimental effect. Since they don't fit after market products, we use the alternatives.

Brick wall, head, not listening....yawn
:rolleyes: Know what you mean !


Don't Lift
23rd February 2004, 01:52
Originally posted by johnfelstead:

Please cut out the attitude, just because people dont agree with your opinion doesnt mean you have to get all arsey about it. tongue.gif redface.gif :rolleyes: Sorry Dad. Which one of us has the attitude? And there's me thinking one is allowed an opinion. Looks like I am going to have to agree with you in future if I'm to have my pocket money on Saturday :rolleyes:

My posts here are an opinion. Head, brick wall was a mickey take. Get over it John, we don't all have to agree with you:p

23rd February 2004, 02:00
Why dont you post under your originally registered username Ben? Your style as that user was pretty agresive and also quite often wrong too if i recall corectly.

Don't Lift is Ben Culverhouse in case you were wondering.

23rd February 2004, 12:08
My car is essentially a road car.. been on the strip once.. would love to do it again or a trackday but cannot afford it.

I monitor intake temp and ambient temp and about to monitor temp at filter too..


24th February 2004, 12:34
At the throttle body would perhaps be more useful for the same effort. Just a suggestion.

24th February 2004, 12:43
Originally posted by harvey:
At the throttle body would perhaps be more useful for the same effort. Just a suggestion. Sorry Harvey, typing error smile.gif

Currnetly monitor intake temp at the throttle body and ambient temperature, but about to move one of them to the filter (or add another temp gauge) and play around with ducting to try and get some cooler air to the filter.


24th February 2004, 13:55

my first Attempt @ wrapping

[ 24. February 2004, 02:00 PM: Message edited by: fuz ]

24th February 2004, 14:34
Its the Purple Glove!!

24th February 2004, 22:05

At the throttlebody?

When I mentioned to people exhaust wrapping the inlet manifold they laughed.. I believe you also thought it wasnt necessary?

Anybody now think it may be an idea? or would it be better to try and loose heat?? :confused:


25th February 2004, 00:26
Makes sense to me to measure the intake temp at the throttle body, it's basically the last place you get chance to measure it and it is after all the temp that the engine will be sucking in, give or take the changes through the inlet manifold.. or was this the jist of your post?


25th February 2004, 03:09
Don't know where you got that from David as I happen to think that although unsightly wrapping the I/M, especially in conjunction with an insulation spacer will help keep the inlet manifold cool.
Got my spacers yet?

25th February 2004, 09:30
I think Harvey was talking about measuring intake temp and David is talking about wrapping it?

Unless I am muddling you are talking about two different although temperature related things?

Simon smile.gif

18th March 2004, 23:50
What does BLING mean? I see the word was used in this thread and as no-one questioned what it means I assume I'm the only one who doesn't have a clue!!!! :rolleyes:

Andrew Carr
19th March 2004, 07:45
Well 'Bling Bling' is a rap term used to describe large showy jewellery and is now in the OED (Ye Gods, what is the world coming to!)

In terms of motor vehicle adornment it refers to anything that Adam and Christian think makes their cars look better :eek:

I guess being immortal makes it hard work keeping up with the latest trends :D


19th March 2004, 08:38
Originally posted by AndrewC:
I guess being immortal makes it hard work keeping up with the latest trends :D

Andrew... PMSL!!


colin c
19th March 2004, 18:56
How much exhaust wrap would be needed to wrap a Hayward and Scott downpipe, what size is best 1" or 2 " and were is the cheapest place to buy it from.

Cheers Colin.

20th March 2004, 09:07
1 roll of longest 1 inch wide available (50 feet IIRC) should do it nicely.

You won't wrap the whole doenpipe, but enough of it to take it down to where it levels off and goes under the car.

Andrew Carr
20th March 2004, 10:06
Personally I would/did use 2" wrap for the downpipe, there are no tight bends like on headers and its easier to get the correct overlap on a ~3" pipe with 2" wrap.

Agree with not wrapping the section which runs under the car.

Andrew the imperialist...

Andrew Carr
20th March 2004, 10:08
Personally I would/did use 50mm wrap for the downpipe, there are no tight bends like on headers and its easier to get the correct overlap on a ~75mm pipe with 50mm wrap.

Agree with not wrapping the section which runs under the car.

Andrew the metricalist...

20th March 2004, 18:07
2" or 50mm wrap comes in 50 foot rolls and is best applied damp/wet and tied on with tie wire and use special tie pliers or borrow a set if just a one off job. Plenty tie wires to make it last. Also black or silver VHT paint when the wrap has dried adds to the wrap life. The alternative is to use tie straps but that works out more expensive except on a one off job.
The DEI wrap has a marker showing the overlap.
My supplier is Nimbus Motorsport 01377 236170. They have a web site but cannot remember address. At Wetwang E. Yorks so convenient for some guys but their postal service is spot on.
Wrap price and ties depends on quantity. VHT paint from memory is 6.50. If you plan to do it regularly get tie pliers and wire which is available from Rally Supply shops or let me know and I will find a source address.
One roll is half used on a 3" D/P.

colin c
20th March 2004, 19:08
Cheers for the replies.

Looked in the Demon Tweeks catalogue at the price of the 50' by 2" exhaust wrap :eek:


20th March 2004, 21:04
I am sure I posted Cooltecs website earlier in the thread.. apparently no good for headers but fine on my downpipe for 30 odd thousand miles so far.. I think 10metres did my downpipe great and was about 20.. iirc


colin c
21st March 2004, 11:54
Hi Simon,

Just been through the whole thread, no email address for Cooltec. 20 sounds better than 50 something + vat from Demon prices ;)


Andrew Carr
21st March 2004, 20:28
As usual Simon is trying to think about two (sic) many things at once :D

Check this: http://bbs.22b.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=9;t=000223