The Evo II upgrade adds high temp silicone hoses to the Wagner Evo I intercooler for the E82 135i, 1M, and E90, E92, and E93 335i. Silicone has better and smoother flow than the stock hose connections. It also works better under higher pressures from more boost (less likelihood of boost leaks).
It's easy to make more boost and more power in a turbocharged engine like the N54 and N55 - until other components show their weaknesses. The stock BMW intercooler on the E82 135i, 1M, and E90, E92, and E93 335i is decent enough for maintaining intake air temps on a stock engine (though there's still room for improvement). But adding more boost will raise intake air temps and lead to fuel and timing adjustments that could actually reduce power levels! If your N54/N55 turbo upgrades are not living up to expectations it could be the rest of your system letting your down.
The Wagner Intercooler for the E82 135i, 1M, and E90, E92, and E93 335i is larger to take advantage of the surface area on the front of the E82, E90, E92, and E93. It uses a stepped design to maximize surface area. With more surface area comes more cooling capability and the Wagner has 85% larger area for 90% more air volume compared to the stock intercooler. CAD and FEA design has optimized the air flow into and out of the heat exchanger thanks to turbulator fins, cast aluminum endtanks, and model-specific silicone hoses. There is less pressure drop than stock which means air velocity stays high. The Wagner Performance line of intercoolers uses tried and true bar and plate layout which has excellent heat soak properties and cooling capability (but are a little heavier than the Competition intercoolers). The weight of the Performance intercooler is 19.8lbs.
One of the best attributes of Wagner intercoolers is their direct fit installation on the E82 135i, 1M, and E90, E92, and E93 335i models. The bumper does not have to be removed or modified and the Evo II fits with any chargepipe desgined for the stock intercooler. Wagner uses a durable anti-corrosive coating that also helps dissipate heat. Installation instructions are included.
E82 / E88 (08-13) > 135i
E82 / E88 (08-13) > 135is
E82 / E88 (08-13) > 1M (11-12)
E90 / E91 / E92 / E93 (06-13) > 335i
E90 / E91 / E92 / E93 (06-13) > 335is
E90 / E91 / E92 / E93 (06-13) > 335xi
E89 Z4 (2009+) > Z4 sDrive35i
E89 Z4 (2009+) > Z4 sDrive35is