i have a d16z6 in my 94 ex. the motor i just out in is used but i inspected the clutch and it looked great. however when i got the car back together and took it for a drive, 3rd and4th gear grind when im cruisin at about 60 in 5th and mash the gas the engine revs up like symptoms of a bad clutch or pressure plate, then you let of the gas and you can feel it catch again. is this a clutch prob or clutch cylinder, or tranny prob? need help!

 

sound like you need a new clutch set..