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When and how much pumaspeed?!
 

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I knew that there would be loud BOV for this car!! I just knew it!!!! I can still remember being chided about wanting one:
"It will screw up the MAF signal"
"It will play havoc with the tune.."
" this is the modern age, who really wants a noisy BOV after all?"


HAHAHAHAAHAH VINDICATION!!
 

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Hah Rev, I was going to call you a wastegate monkey, but then saw your occupation was a wastgate monkey.
 

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:confused: I just don't get it.
 

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Sounds cool and a huge waste of MPG!
 

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Chad said:
Sounds cool and a huge waste of MPG!
Virtually all blow through turbo engines have a blow off valve. Just because it vents to the air so you hear it instead of back into the air box has no baring on the MPG.
 

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Virtually all blow through turbo engines have a blow off valve. Just because it vents to the air so you hear it instead of back into the air box has no baring on the MPG.
I think blow back into the air box is for emission standards
 

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Catch can for emissions? You'll need to explain that one. With regard to the BOV effecting mileage, it depends on how the ecu deals with metered air. And there shouldn't be any emissions related to the vented air itself.
 

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SURE! An oil catch can in put 'in line' with the PCV system. The PCV system takes the oil vapor that is generated by the engines heating of the oil as it runs. These vapors collect inside the block in the area called the crank case.
These vapors are then picked up by the intake system and fed into the cylinders so it can be burned in the combustion process.
Unfortunately, this causes some emissions and can POTENTIALLY lower the overall octane of the fuel and cause carbon build up on key engine parts.
PCV= Positive Crankcase Ventilation

An oil catch can grabs these vapors and condenses it into liquid oil when then, after a while has to be drained manually. This is usually done at oil change time and poured in with the used oil to be recycled.
 

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Discussion Starter #19
hammer, this is only theoreticly :) you did not mention any difference in mpg use.
to blow of the pressure is more healthy for the turbine....and sounds much cooler :p
 

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hammer, this is only theoreticly :) you did not mention any difference in mpg use.
to blow of the pressure is more healthy for the turbine....and sounds much cooler :p
To put it simply it makes the engine run with a more fuel rich mix if the valve is past the MAF sensor. The sensor will read X psi but it will be discharged to X-Y psi. This is why diverting back into the turbo rather than dumping maintains fuel economy and helps with lag. But I do agree, they sound sooo good.

A little theoretical example:
Turbo (17psi) -----> MAF (Calculates air/fuel mapping for 17psi) -----> BOV (depressurizes to 10psi) -----> ECU (now maps the fuel injectors for 17psi) = Fuel dump.

This of course can be corrected but who really wants to remap a whole engine :D

Hope this helps, correct me if I'm wrong.
 
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