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Anyone know much about these? Sounded very silly, but then a YouTuber I frequently watch released a video testing one out and also walked through a scientific study that showed some impressive gains.

https://youtu.be/FrFeaNGDnOk

Something to note, the percentage of gain is more important than the numbers. The study was done on a large Diesel so don't expect a 2L to get those torque increases. If you just take the percentage change though of 10 percent more torque lower in the range it would be cool.
 

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From what I understand, given the location of the Giulia's turbo, I don't see any possiblity of an application that would fit and do anything useful.
 

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2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
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On this principal, perhaps removing the iron housing of the turbo, polishing the outside, and having it platinum plated (or similar) would provide more benefit? Might be a few hundred dollars instead of tens of dollars, but doesn't require extra room.

The objective being to reduce the emissivity of the turbo. At high temperatures most of the heat is given off as IR radiation and a low E surface will give off less heat (by definition). At dull red temperatures, platinum E is about 1/10th the value of cast iron. This decreases to around 1/20th at lower temps and increases to around 1/2 at white hot. However, at lower temps the IR radiation drops off and conduction and convection become the dominant heat transfer mechanism. At white hot platinum will oxidize and iron might be able to migrate through it.

Of course, it would look good too :)
 

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2020 Alfa Romeo Giulia Sport Ti AWD
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I installed on my Fiat 500 Abarth, but it wasn't for performance, it was to limit the immense heat I had coming off my tuned turbo.

Any performance gain was incremental in my mind. It could also be argued that turbo life is reduced by turbo blankets. So I'd only install on if there was huge heat coming off the Alfa turbo.
 

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My turbo on my other car has a ceramic coated turbo hot side to help protect wiring and hoses nearby. Keeping exhaust gases hotter generally increases velocity but the turbine is the restriction so it ends up not doing much for performance.

I've used a turbo blanket before and they tend to fall apart and fiberglass fibers start coming out. Not my first choice..
 

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The referenced study of performance impact was on a 6.7 liter diesel engine that showed 0.3 Second improvement in turbo spool up. There were hints about fuel efficiency improvements, but not really anything about "steady state" horsepower increases.

However, that spool up time was already enormous, in the 4-6 second range. The practicality of how heat gets transferred into the turbo housing for said diesel may be completely different than for a high performance gas engine. In particular, the gas engine turbo may be spooled up faster than it can heat up. To this end it might be better to insulate the inside of the turbo and/or exhaust manifold. A low E coating on the inside of said channels might get there, I do not know. I previously suggested platinum, as it is low E and can survive the harsh environment. On the inside, platinum might cause some undesirable chemical reactions, though.

I am not sure that a ceramic/enamel coating provides significant insulation.

A "space blanket" of platinum foil might hold up better than the fiber based product. However, it would get dirty (dirty platinum is not low E) and would be hard to clean. Aluminum is lower E than platinum and aluminum foil could be considered an expendable, but I am not sure it would survive full operating temperature for any time at all.
 

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It is noteworthy that a web search will show that platinum plating is used in gas turbine engines to improve thermal efficiency and reduce corrosion issues.
 

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It's all about cost vs benefit. Sure you could platinum coat it but I can't imagine the cost of that. Good ceramic coatings help insulate the pipe quite a bit. Diesel exhaust gas temperatures are much higher than gas engines, so they benefit even more from insulating the manifold or turbo.

It's similar to running 3 dyno pulls back to back. The second and third pulls usually have boost threshold at lower rpm because the pipes/turbo have heated up.

On my track car the coated pipes are noticeably cooler on the outside than when they were plain just by putting my hand near it after running the car. Under hood temperatures improved too.
 

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It's all about cost vs benefit. Sure you could platinum coat it but I can't imagine the cost of that. Good ceramic coatings help insulate the pipe quite a bit. Diesel exhaust gas temperatures are much higher than gas engines, so they benefit even more from insulating the manifold or turbo.

It's similar to running 3 dyno pulls back to back. The second and third pulls usually have boost threshold at lower rpm because the pipes/turbo have heated up.

On my track car the coated pipes are noticeably cooler on the outside than when they were plain just by putting my hand near it after running the car. Under hood temperatures improved too.
The amount of platinum used in platinum plating is very small, the cost is all in the processing rather than the material. The cost of ceramic coating was quite high when I priced re-coating my Etype exhaust manifold 20 years ago. I expect that the cost is higher now. Differential thermal expansion can be a problem for brittle ceramic coatings. Porosity is the primary enemy of metal platings. Electroplating the inner surfaces of materials can be difficult do to the way the electric currents want to flow. However, an old jewelers trick of "painting" on the plating using an electrically charged paint brush might work.

I do not know if platinum plating of cast iron is feasible. Gas turbines are made of high alloy steel, nickel alloys, and titanium, all of which have a different crystal structure than cast iron. Metal to metal adhesion is dependent largely on crystal structure and crystal dimension compatibility. Many platings require multiple coatings to get adhesion; for example chrome over iron requires 3 layers to get it to "stick" reliably and multi-layer plating runs up the processing cost.

Diesel exhaust temps for the same power production are significantly lower than gas exhaust temps. Diesel smog systems have problems with the exhaust gas being too low and measures have to be taken to compensate (use a valve to raise temperatures or add DEF to lower the catalytic ignition temperature, or both). Diesel soot happens because the combustion temperature drops too low due to dropping pressures during the power stroke to complete combustion. The pressure drops more on a diesel during the power stroke due to the high compression ratio of diesel engines. Diesels also are "lean burn", so that there is more air going through the system to heat up compared to a gas engine. Diesels have a higher combustion temperature than gas engines, but that should not be confused with the exhaust temperature.

With direct injection in a gas engine some of these differences will be reduced since the direct injection gas engine is behaving more like a diesel.
 
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