i got a 96 b18b1 in an 89 dx and i have a very annoying problem... whenever i shift into 4th gear after roughly 3k-3.5k rpms it grinds. no matter what i try it will always grind, unless i let the revs go all the way down to almost idle. other than that, shifting below 3k rpms it will go into 4th gear totally fine. i re-tightened my linkage to make sure that wasnt the problem but it still does it anyways... and it only grinds from 3rd to 4th, i can be in 5th gear at 4k rpms and drop it into 4th and it will go in totally fine... any suggestions?