Bit of a strange one… so b20 vtec, ran fine beforehand, has been mapped done 4k miles and track sessions ran perfect… I put it in the unit over winter so its sat for about 4months maybe… started it up and ran fine until it got hot, the timing belt is moving over and rubbing on the bottom plastic cover slightly. Both crank pulley washers/guides are on and everything is tight. Like I say I literally parked it up and now its doing this. Took the rocker cover off and the belt is sitting right on the edge of the cam gears rather than central, I can move it back along and the rubbing stops but then after a few revolutions of the engine they’ve pulled back along. Any ideas?