Turbo Blankets -- I'm a Little Confused (valve, exhaust, engine)

[Exitus Acta Probat]

I thought that turbos needed to cool off before turning a car off, because if the turbos don't, then it's bad for them and they'll fail prematurely. Is this still true? If it is, then a turbo blanket seems like a really bad idea to me. I'm asking because on other forums people are talking about how much they love their turbo blankets and they state that the blankets aren't damaging their turbos. What's the real deal for modern turbos?

[Electrician4you]

Turbo blankets go on the exhaust side of the turbo housing. It basically a flexible heat sink

[wankel7]

If it is watercooled and oil lubricated don't worry about it.

[Cheesesteak Cravings]

Originally Posted by Exitus Acta Probat

I thought that turbos needed to cool off before turning a car off, because if the turbos don't, then it's bad for them and they'll fail prematurely. Is this still true? If it is, then a turbo blanket seems like a really bad idea to me. I'm asking because on other forums people are talking about how much they love their turbo blankets and they state that the blankets aren't damaging their turbos. What's the real deal for modern turbos?

The purpose of the blanket is to reduce heat soaking of the compressor side (the turbine that draws in air). On that note, there are also theories that keeping the exhaust gases hot, it can improve spool. Not sure if it would be at all noticeable, but if anything it would be a minor benefit to the major benefit for preventing heat soaking of the compressor side, and of the engine bay, especially if you have a top mount intercooler.

[Blue biker]

Letting a turbo cool off is more to let it slow down, if it's turning 50,000 rpm and you just shut the engine off the turbo loses lubrication.

[GTOlover]

Modern turbocharged cars are so much easier to maintain then the older non-intercooled (oil-cooled only) or early intercooled ones from the late 1970's and mid-late 90's that needed a turbo timer to cool the turbos down to avoid cooking the oil inside the turbo

[MckinneyOwnr]

The blankets serve two purposes. They are intended to keep the turbine housing heat from heating up the charge air being fed back into the engine (while also keeping that heat from the radiating into the rest of the engine bay) and they are also designed to keep exhaust temperatures higher, because hotter air moves quicker through an exhaust system than cold air. So the hotter the exhaust temp, the faster the air flow. The faster you can move air through an engine, the more horsepower you will be making.

[Fargobound]

I think people were putting shields on their turbo second gen MINIs only to find that the factory did their homework better than the aftermarket. The shield would cause so much heat build up that it would melt a hole in the composite valve cover close by.
Today’s turbo cars are nothing like yesterdays turbo cars.

Fuel management
Oils
Cooling efficiency
Turbo design

Have all gotten better.

The aftermarket sometimes invents solutions for problems that are not there.

[rbohm]

Originally Posted by MckinneyOwnr

The blankets serve two purposes. They are intended to keep the turbine housing heat from heating up the charge air being fed back into the engine (while also keeping that heat from the radiating into the rest of the engine bay) and they are also designed to keep exhaust temperatures higher, because hotter air moves quicker through an exhaust system than cold air. So the hotter the exhaust temp, the faster the air flow. The faster you can move air through an engine, the more horsepower you will be making.

well said.

[Exitus Acta Probat]

Thanks for the replies. So I'm guessing nobody who has replied so far and who is ASE certified has had to replace a turbo due to its failure as a result of a blanket?