[pgtatx]

Core efficiency is important... Both it's efficiency in ability to dissipate heat, and it's ability to flow air...

If you have 2 IC cores with the same dimensions... why does one produce a larger drop in pressure across the core than the other other one. If you look at a cross section of 2 cores... 1 being a name brand top core, and the other being an Ebay knock off, you'll see the answers.

Exterior dimensions alone will not tell you what the core will actually flow. Companies take guesstimated based on size, but reall companies actually test.

If an IC is too small or way too large (which is a common issue amongst the ricer community), you will end up with a not so fun situation.

If you have a turbo that pushes X amount of air, and then you have 5 ft of piping, and a huge core that flows XXX amount of air... you will end up woth significantly slower spool, and show a loss of pressure across the core. People think bigger is better, but that is not true...

If the turbo you have flows XXX amount of air, and you use an IC that flows X amount of air... you will be creating back pressure and significantly increasing the temp of the air. You may even see some some surging...

Find an optimally designed IC... good core and proper end tank design... and you will get the most out of the set up.