i have a 2.5r w/o.s 18tm w/trinity hi-flow pipe-i used the stock coupler to connect um cause the trinity manifold wouldnt work w/o.s-make sure u tighten um w/ heavy duty zip ties-I've had no problems and will lift front wheels from a dead stop to a 4-6mph roll-will even lift um from a higher speed-3-5inches and roll out w/ that little wheelie-hahaha