Air filter inside of the engine vs outside, who wins?

At beginning I thought having a long intake inlet (pre turbo) will affect the spooling time negatively (according to my logs), however, I was wrong, it was due to more restrictive air filter used during that setup.

Today I compared both setups in the same environment, it turned out CAI setup was way colder around 13 degrees less and keeping a similar spooling curve.

red numbers = MAT (manifold air temperature).
yellow numbers = Boost in PSI

Inlet pre-turbo pipe is 4inch. And keep in mind I'm using water to air IC with the water pump and fan off during those pulls.

I would say this might be a different story if you use a more restrictive pre turbo intake diameter as the turbo will work harder (getting warmer) to suck the air.

 

Nice Job. Do the same test after sitting at the lights for 5 mins , that where you will see some huge numbers.
Did you do any testing with W/A IC working ?

 

Thanks Brett.

Yesterday I did some logging with the W/A IC working, although ambient temperature was slightly warmer than the last logs, the results were great.

Ambient temperature: 15 degrees Celsius.



This was while doing few pulls (and after 30 minutes of driving, to give enough time to warm up the water). Max temp was 17.4 and when cruising around town I saw nearly ambient temperatures.
Many people consider W/A IC setups not worth the investment for street setups, while is true that adding more complexity to the car is not good, the benefits outweighs the cost, at least in my case it does.

Next logging will be W/A IC off/on during the same day to have more accurate results.

I would love to see some A/A IC log.

 

Something interesting, after the W/A IC was working you can see the MAT line getting choppy, possibly it's related with the speed of water circulating.