Thinking about sticking a cone filter on the end of the turbo in my 650cc car engine. Just got to thinking about the effect of temperature on the turbo. I know that hot air causes less fuel to be injected, and can increase fuel efficiency, but was wondering if the hot air would reduce compressor efficiency in a way that would decrease gas mileage. I would tap the end of the filter and install a preturbo nozzle to drop temps to bring back performance. I already have the pre-turbo setup working, but was considering increasing the flow since I would be increasing the temperature

 

the hotter charge into the engine might need MORE fuel to keep combustion temps under control and ruin the percieved efficiency gain from the reduced cylinder density and its fueling requirements.

cooler and denser inlet air should mean cooler and denser into the engine, yeah the lb/min of fuel might be more on paper but i reckon its still a winner.

flipside is, wouldnt the hotter and less dense inlet air from the engine compartment be "easier" for the compressor to churn up due to less drag on the wheel?

dont know much really, but cold air is good, thinking too much is baaaad

 

fixed
just cut the last bit out

 

do this math when u get a chance..
p2/p1 ratio = 14.7 + "boost in psi" / 14.7

if the air cleaner is restrictive, the 14.7 number ( 1 atmosphere ) gets changed to a less numberm due to the restriction of aircleaner, and less air pressure at the inducer of the turbo.
try the numbers ..eg 14.7 , then use 13 ..
all with the same booost number, and then have a look on a compressor map.
you may be surprised to see what effect it has.
sure i can tell you the answer, but having a play with those numbers , u will learn stuff

 

It's not the resriction that I am worried about, it is the temperature of the air. A filter on the turbo will decrease restriction but increase temperature.

 

The math wantabe suggested doing is how you quantify the loss due to temperature and the gain due to less restriction so that the two can be compared.

Should I have capatalized wantabe? It is a proper noun but he himself does not have it capatalized. I'm going crazy!

 

hello andy

 

So your main concern is that the Air Filter is adding a temperature change to the inlet air?

What I'd be concerned with are temps at WOT, Pre-Turbo can only do a little to drop these it's mainly for adding 1psi back to the Compressor Map, POST-turbo is what you should look into as a denser charge has the ability to make more power and be knock resistant.

 

Is it true that 1* of inlet air temp change equals 1* of exh temp change?

Dave

 

what goes in , must come out
energy cannot be created or distroyed
BUT , transferred is ok.
eg via intercooler transferring the ITA temp to water...or extra fuel to turn liquid into vapor ...etc,etc