These are our billet wheel version of our ko4 025/26. These turbos utilize a slightly bigger / taller compressor wheel and are rated for 28 psi. Assembly of each set is done in house and all machine work on our housings is done locally. These are great for e85 built motor application and come with one bar wastegates and an 18 month unlimited mile warranty. Wastegates are set prior to shipping at 9 psi however please verify post install both are set to 8-12 psi depending on tuners recommendation.