IMO? The Conforti looks better built (take a look and compare for yourself, links below), and it has a straighter intake path. The ECIS has a 90-degree bend in the piping where in the Conforti it's nearly straight.
Of course, the ECIS costs less and it's a great intake nevertheless. If you're willing to pay a little more I'd recommend the Conforti. The ECIS only costs $250 (+ shipping) where the Conforti is $380 (shipped) from KO Performance.
The big difference with the conforti is the large velocity stack that the filter attaches to and also the fact that it has a straight intake tube versus curved, this gives the Conforti several HP over the ECIS. Now price versus performance is a different story. Similarly the GruppeM uses a straight intake tube but is has a "V" shaped filter which would allow more straight through airflow at a higer velocity and therefore assist in producing a higher output than Conforti. Now based on the very few postings from Jim Conforti himself, he provided no significant evidence do disprove that the GruppeM's performance was sub-par. In fact dyno tests showed the GruppeM performed better. Again, the bottom line is price/style versus performance.
I'd say if your not into looks and want some performance, head to the group buy section, there is a ECIS style CAI going for $229.
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