When I got my cortina it was running a 1.6 and someone had fitted a 5 speed. It ran fine.
I have recently finished a 2.0 conversion. At the same time I fitted new wheels and tyres. First run out it was ok until I hit 55 mph, then bad vibrations start happening. They come in really bad at 60-64mph ease off a touch at 70, and then get really bad again at 75.
Most noticeable place I can feel it is through the gearstick, it vibrates and buzzes so bad that I cant put my hand on it. I can also feel it coming up my right leg from the accelerator pedal.
I thought it was coming from my new wheels, I bought new tyres and a friend of my lass fitted them on the cheap but he didnt balance them, I took them and got them balanced this morning. Had another run out today but the problem is still there.
As a side note the new engine seems fine, it revs ok, and pulls nicely and quickly despite the vibrations.
Any ideas what could be causing this? people at the meet today suggested the prop shaft, but this was fine before the engine swap and hasnt been removed or touched. Someone else ages ago mentioned the clutch not being properly aligned. Any advice greatly appreciated cos I am stuck with this.