Ceramic coating exhaust manifolds

[RobXjcoupe]

My stainless manifolds have gone rusty and I'm considering getting them ceramic coated but I'm a complete novice with this kind of thing.
As the manifolds are not new, would a shot blast surface finish be ok to ceramic coat rather than being polished up first? Also is it ok to coat the separate catalytic converters or is it best to leave those alone?
As always thanks in advance for any info
Rob

[RobXjcoupe]

Thanks for the reply.
I was mooching around my car earlier and thought if I remove and polish the manifolds again is it necessary before ceramic coating. I thought a shot blast surface would give a better key but better to ask first.
Are colour options available in the ceramic coating as I was thinking of black?

[RobXjcoupe]

mk1fan said:

Performance 1 have a colour chart on their website.

Camcoat is another provider. I think they have a colour chart too.

Had a look at performance 1 and ooo choice of colours
Now I'm thinking either tungsten grey or perhaps the gold as my car is a navy blue.
Lots of pulleys to clean up too. So maybe a chrome, silver and grey engine or perhaps gold and grey. If I get those manifolds done first though as I'm after a re-paint and don't want to mark any new paint by donking it with a rusty exhaust manifold :s

[RobXjcoupe]

steve-V8s said:

If you are taking the manifolds off it is worth having a go at matching them to the ports on the heads. The match on mine was very poor and I gained about 20ft/lb in the mid range.

Tried various coatings and ended up with Zircotec which has lasted very well. I did it to reduce heat rather than for cosmetic reasons.

I didn't think of matching the ports.
I must say although the coating is for cosmetic purposes the heat will reduce but doesn't it just make the pipes under the car hotter? So yes reduced under bonnet temperatures but that heat has to escape somewhere else.

[RobXjcoupe]

steve-V8s said:

Suppose the heat has to go somewhere, probably finds its way out the back slightly hotter, some say gas flow is better when hotter.

My aim was to reduce the measured inlet air temperature and the actual inlet manifold temperature. Once you get going the actual air temperature drops fairly quickly but the sensor and manifold takes a while to catch up. In my case if the ecu thinks the air is warm it backs off the ignition advance as a precaution so you lose a fair few horses. If you are doing something competitive you want full power from the start not a bit later, for road use it probably doesn't matter quite so much provided you are not running too much advance.

I won't be doing anything competitive, but my car needs tlc after some minor and major life set backs. Hopefully back at work next month to pay for the nice things 😊

[RobXjcoupe]

griffdude said:

Sorry to ask such a dumb question, but rusty stainless manifolds? Thought stainless manifolds didn't rust?

I've had a set of CliveF's stainless manifolds on my Griff for about 8 years & apart from now looking bronze in colour, they're still as shiny as new.

It's not a dumb question but as the name says it's Stainless not stainfree steel will eventually corode with continued cycles of exhaust heat going through it.
My manifolds were replaced in 2004 and have done the bronze colour with bits of corrosion appearing now. The ceramic coating will help prolong the surface finish. TBH a regular steel manifold that's been ceramic coated would be a good choice but most aftermarket manifolds are stainless as it's seen as a premium choice.

[RobXjcoupe]

bobfather said:

steve-V8s said:

There are lots of different grade of stainless steel, some are more prone to rust than others even the higher grades like 314 will rust if abraded with something ferrous. An exhaust is probably made from 304 which will rust a bit particularly where it has been welded.

The classic case is a stainless steel sink which has been cleaned with wire wool will quickly develop surface rust. Another misconception about stainless is it is non magnetic. It starts off that way but the more you work it the more readily you can stick a magnet to it.

Very true. Clive F appears to use good grade stainless, ACT on the other hand do not. They outsource the manufacture of their StSt manifolds and the manufacturer probably uses the cheapest material available so their StSt manifolds rust badly and quickly. ACT avoid this by accusing the installer of contamination during installation but as I fitted both manifolds and Clive's Y piece at the same time I am convinced that my ACT manifolds are expensive rubbish and Clive's Y piece is great quality

My tvr exhaust manifolds are act and about 13 years old, they are not totally rusty but they are fairly dark with rust spots on them. I do also have a Hayward and Scott exhaust manifold on my xj coupe which is slightly older perhaps 16 years old and looks similar in appearance to the tvr. Unless I build a show car that's never used a stainless exhaust manifold will darken with heat and corrode as mentioned already. Stainless is only roughly 10% chrome anyway and put through cycles of exhaust heat and possibly water splash if used whilst driving in the rain it will corode. Probably but very expensive would be to chrome plate the stainless which I think needs to be nickel first then copper then the chrome.

[RobXjcoupe]

Toma500 said:

These are ceramic coated black been done nearly 2 yrs gone a little grey in certain areas but coating not coming off i think HHC got them done by Performance 1 for me when they removed them i got the heat shielding renewed as well , these manifolds have had the precats removed and that together with the coatings made a fair bit of difference .

I was thinking just that, remove manifolds and renew foil heat shields before bolting all back together

[RobXjcoupe]

Toma500 said:

RobXjcoupe said:

I was thinking just that, remove manifolds and renew foil heat shields before bolting all back together

Go for it a very worthwhile mod getting rid of the pre-cats you dont apparrently need them the coating im not certain makes a lot of difference but looks nice ,and my heat shielding had seen better days and my left knee was getting warm .you can inspect the main cat in the y piece as well make sure its all ok wear ppe though its got some nasty stuff in them .all in all i guess its maybe 25%-30% less hot under the bonnet with all this done ,would be more if you totally de-catted.

I can't run no cats as my car is a 95 and tbh I'm getting fed up of bolting and unbolting the removalable cats and straight through pipes accordingly. I do understand what you are saying though
I'm just after a wipe down engine bay rather than polishing, easier to replace a few corroded bolts than polishing chrome and awkwardly shaped exhaust manifolds lol

[RobXjcoupe]

Might do the rocker covers as well

[RobXjcoupe]

mk1fan said:

I did the rocker covers on the S and I wouldn't do it again. No benefit. Painted and polished covers look better imho and are cheaper.

My current rocker covers were chrome polished but I haven't kept it up so now it's looking naff. Hence I thought a nice heavy duty heat resistance coating to wipe down when a bit dirty.
Might just colour code the rocker covers to body colour then

[RobXjcoupe]

Frio3535 said:

My old griff - manifolds are like a centre piece to the engine so I got them done to match the colour of the interior.

Brave colour but looks amazing 👍

[RobXjcoupe]

Chim450 said:

I recently got my Speed 6 manifolds coated at Zircotec for £345. More expensive than Camcoat and F1 but apparently much more durable as the process is plasma coating rather than “painting” and curing as I believe the others do.
I did quite a lot of research and found that quite a few people found the coating deteriorated quite quickly when it was the paint/cure type but no one had found this with the plasma coating.
You pays your money and takes your choice I suppose.

Agreed I wouldn't want a paint type application, it needs to be finish that lasts a good few years.
Just thinking old jag cast iron exhaust manifolds used to be black enamel and they lasted decades