I bought a Fabworx sidewinder manifold. The welds had pinholes, the tubes were almost too short, stay away from this brand. When I had my log mani, I took a grinder to it and ported it. Made 270 at the wheels on a mustang dyno, on a bone stock k20a3. The log manifolds are great for drivable (230-350) horsepower. I stay away from the stainless log manifolds. If you can find a cast iron you'd be in good shape.