Exhaust finish : aluminizing vs ceramic coating?

[TTM]

Good Afternoon Gentlemen,

I have just had the silencer refurbished on the Ace and am now looking at various finish options.
I believe the previous owner had the complete exhaust aluminized, from the manifolds to the tip, as suggested by its white colour. However it seems that aluminizing favours heat radiation. I cannot say this is something I am interested in, which brings me now to consider ceramic coating instead, specifically to avoid heat radiation.

I am very interested to hear the opinions of the good folks on here.
Going stainless is not an option as I wish to retain the original exhaust.

Thanks.

[Vincent998]

Hi:

From your post, I can't tell what exactly your objective is - appearance, corrosion reduction, heat reduction, or perhaps all of them? Although I have not had experience with aluminizing, I have a bit with ceramic coating and with heat wrap. I found that ceramic on my V8 headers eventually flaked off and did not seem to do much to reduce heat in the engine compartment. What I did then was to heat wrap the headers from the flanges all the way down to the exhaust pipes. The result was that header temperature was literally reduced by half; temp measured with an IR gun went from 600 to 300 degrees and it made a huge difference in under hood temperature and also in firewall temperature and probably in the life of all the gadgets under the hood (bonnet).

I hope this is helpful.
David

[TTM]

Hello David,

Thank you for your interest and feedback.
I am mostly interested in protection against corrosion.
Heat wrap is probably the most effective solution to prevent heat radiation but I experienced a collapsed (Inconel) exhaust in the past due to excessive heat because of wrapping, and this is something I would quite gladly avoid with the well-used 60 year old exhaust of the Ace. I will always accept to cook a little bit sitting at the wheel rather than risking damaging the exhaust in any way.

Thomas

[Norman]

I have a zirconium finish on the exhaust of my 2.6, both on the cast iron manifolds and the stainless-steel Y-piece that joins their outputs together, and can't honestly say I've noticed any difference in heat soak. I was offered a choice of colour and chose silver, but the finish pealed off the stainless in no time, leaving the white base, which looks OK in its own right and, 15,000 miles on, still seems intact. So if you go this route and have the option of omitting the finish coat, that might be worth considering.

[TTM]

Thank you Norman for the feedback.
I brought the complete exhaust to a local company who do ceramic coatings which can withstand 1000°C on all sorts of metallic parts (including guns...) and I have chosen a satin black finish. They offer gold, black and various shades of silver but went for black in the end as I thought that would suit the almost black, very dark green colour of the car quite well.
I can't wait to get the exhaust back as having it refinished has been on the to-do list for years and I'm quite excited by how nicer the car will certainly look with a nicely finished exhaust and a silencer which doesn't look anymore like it's going to fall apart!

[TTM]

Pleased to report that the exhaust is back on the car. The ceramic treatment, claimed to reduce perceived temperature by 30% to 40%, has made a significant difference in under-bonnet temperatures and the cabin does not feel like the oven it used to be. I can open the bonnet after a drive and proceed with various adjustments without risking to burn my fingers anymore. It is perhaps too early to draw any conclusion regarding durability but so far this looks like money well spent.

[Vincent998]

Did you measure the actual temperature of the manifold with an IR gun before having it coated? Data would be very interesting! You could measure it now and measure the temp on a similar car with an uncoated manifold to get an accurate idea of how effective the coating is..

David

[TTM]

Well David, sorry to say I did not think about doing pre and post measurements. I do not even have an IR gun.
I am positive however that this is not a placebo effect and that the car is more comfortable to drive with less heat radiating from the exhaust, at least in the current warm Summer weather. I may have a different opinion on cold days!