I've run two different sets of injectors from Formula 1 for several years ( 1. 5's & 3. 8's) I love them. The 1. 5's have been sitting in storage for a couple of years since the bigger sticks have been in. Since I retired the truck as my daily driver & only use it to haul hay & horses now I've been thinking about switching back. I just contacted my vendor (Rip) about having them tested. He told me that it's Don's policy to clean & pop test for the price of shipping!