turbo better when hot or cold?

[wayeshock4]

Is it better when the turbo is hot or when its cold? My friend insists on its better when its cold. and wants to insulate and make all these vents to keep it cold? any help would be great thanks!


Devin

 

[DSMSpyder99]

colder is more DENSE than hot air there for colder air has more oxygen molecules making it more effecient when it combust. Colder air is ALWAYS better than hotter air for N/A or FI

 

[TurboJunky]

I think he's referring to the turbo in itself being hot or cold.

FWIW, I've seen tons of turbos in custom setups wrapped in heat shielding material...

 

[wayeshock4]

yea i mean the turbo itsself... like do u want it to be hot or cool? ive been told it been hot spools better

 

[DSMSpyder99]

you will NEVER get the ACTUAL turbo to be cold if you have an EGT gauge you can see this plan and simple :laugh: Just crusing at 75-80MPH (SoCAL freeway speeds) my EGT peak around 1300*F

 

[xcelr8n]

I think he's referring to the turbo in itself being hot or cold.

FWIW, I've seen tons of turbos in custom setups wrapped in heat shielding material...

but thats not heat shielding wrap, its heat insulating wrap... to keep the heat in, wheres that pic of the glowing exhuast when you need it

 

[blcknspo0ln]

i'd like to see a turbo be actually cool enough to touch after a couple minutes of spirited driving :laugh:

 

[98spydert]

yea i mean the turbo itsself... like do u want it to be hot or cool? ive been told it been hot spools better

What people mean when they say that is to keep the heat moving through the turbo by insulating it. Yes it's better to have the entire manifold, the hot side of the turbo, o2 housing, and down pipe wrapped or at least heat coated with jet hot or something.
I have my o2 housing coated, I plan on wrapping my down pipe and getting the rest coated for an example, not only to keep the heat "flowing" but to reduce under hood temps a little.

 

[vteg]

Turbine housing is better hot, and compressor is better cold.

Since they are connected there is a conflict of interest

 

[heavyD]

Turbine housing is better hot, and compressor is better cold.

Since they are connected there is a conflict of interest

That is the correct answer. You need the turbine housing hot as it is the heat energy of the exhaust gas that is the motive for the turbine wheel. On the compressor side you want the air to be cool as the dense air contains more O2 molecules. That is why we have intercoolers on our cars.

 

[Nebo]

If you retain the heat in the exhaust housing from either insulating or by a thermal barrier coating wouldnt the exhaust housing have a better chance of cracking from retaining in all that heat??

 

[dsm-onster]

Hmm, turbos and even exhaust manifolds are DESIGNED to function at 1300 degree teperatures. it's the problems the heat radiating from them causes to surrounding components and air that is going into the intake manifold for us who've cut our air cans. Bigshots on the track at times insulate the turbo with kevlar and other substances TO KEEP HEAT IN. The theory is that less energy leaving the system the more ove it is converted to spoolup. I don't know for sure of the validity of the theory or whether it would even help on a street set up. Nevertheless, i would focus on maybe wrapping the exhaust system in the engine bay including the turbo and not waist time/money on venting air to the turbo.