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Old 09-13-2017, 08:45 PM   #25 (permalink)
cRiPpLe_rOoStEr
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Quote:
Originally Posted by ProDigit View Post
I would believe that on a hot engine, water vapor increases performance, especially on a turbo car.
Since the added mass, creates added expansion, your turbo should rev higher.
Since the higher humidity added to the intake stream is likely to retain more of the heat that would otherwise be wasted through the engine cooling system, it would benefit basically every engine, not just the forced-induction ones.


Quote:
Routing the AC drain pipe to a sponge in the air intake (or wetting the filter), is a great idea to both increase filter effectiveness, as well as cooling down the intercooler, and at the exhaust point, revving up the turbo.

If you have an eco turbo engine, you can expect a little more torque at lower revs.

If you are running a performance engine, and can choose between 2 types of turbo, it might benefit to take the larger size turbo (lag, but also much higher HP), if your engine can handle the increase in power.

The water vapor of the AC unit is too little to make a big difference, but might actually benefit eco turbo engines, in hot summer days.
No wonder BMW is already messing with a similar setup.


Quote:
Cons of water injection is:
Much faster exhaust rusting.
Water coming out of the tailpipe.
White smoke coming out of the tailpipe (might not pass regulations on some places)
Exhaust rusting depends on many factors, ranging from the material to the amount of vapor that would end up condensing inside the muffler. Under normal operation, it would not be too likely for water to come out of the tailpipe in liquid phase. When it comes to white smoke, if it doesn't have that typical smell like burnt oil we usually notice in poorly-mantained beaters it might not lead to a fail on inspections.


Quote:
Not much is known about how the water interacts with engine oil, and engine bearings and rods.
As long as it doesn't condensate inside the engine, which by the way sounds quite unlikely to happen, there would be no contamination to the engine oil. Even during the expansion at the power stroke, piston temperatures might be high enought to prevent the water to condense.
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