Hi guys i useally read more then write here but i have a trouble with my Z , I got a fresh motor rebuild, new everything , when i drive on the highway drive at about 60-70 mph and when i let off the gas and press it again it feels like something rams in the transmission and then everything gets back to normal ? I think its the Diff or clutch but im not sure . Thank you .
EDIT: forgot to mention its a 280Z 1978