I have a greddy turbo kit, everything works flawlessly besides the downpipe to turbo vband setup. It is a 2.5" setup, i have put on two different 2.5" clamps and they are a tad bit to small to tighten because I cannot get the nut on due to lack of thread. I put on a 2.75" clamp today and it clamped all the way down to the max but not tight enough to fully seal it. Is there a size that's in-between a 2.5" and 2.75?