Question about rear engine air supply !

[mikezen]

Hi !
On the opposite of the front engine (see fig 75 p 358 of the parts catalog), there is definitely no air duct to guide some fresh air directly on the rear air filter (see fig 76 p 360 of the parts catalog) !
This means that the air coming in the rear engine is just "sucked" trough the air filter by the turbocharger, among a volume of air that has already been heated by the engine's temperature ??!!
For a carburetted engine, this would be equivalent to try to take off with the carburettor heat on !
Don't you think this design leads to a big reduction of rear engine performance, especially in emergency single engine operation ?
And yet, there is no critical engine for the pressurized version of the Cessna 337...
Is it because the rear propeller continuously "sucks" the hot air between the engine and its cowling ?
Very strange : have you any explanation ?
Thanks for your answers !