I'm going to wear out this forum with my newbie questions but here is another one. Since I bought the '70 4/4 car it has never gone above 45 mph while I was busy tending to minor things. Yesterday I had the chance to drive it at a decent speed. I got it up to 76 mph by GPS( the speedo doesn't work yet). It ran great and held the road well with what appears to be plenty of power left if I want to try it. However, at about 46 mph it developed a severe whistling noise. I depressed the clutch and it didn't go away. I backed off on the gas and it was still there. It continued to make the noise even up to the 76 mph figure. It almost sounds like a metallic ringing noise but for the life of me I can't figure it out. I taped up any firewall openings, the windscreens rubber area, windwings, bonnet belt, and any other areas where I felt that the air could be causing the noise with no positive results. Any ideas or am I going to be trying to live with this forever? The wife won't ride in the car with that noise so I have a serious problem! The engine when reved up at a standstill is very quiet with little valve train noise and the are no obvious mechanical items that are loose. I have had it on my lift for a couple of weeks while I was detailing the chassis and engine bay and during this time I tightened all hardware and carefully inspected everything there. Nothing seems out of place. Once the road speed drops below 45 mph the noise goes away. I think that I can rule out the gearbox and engine so that is good, but where else can I look. Obviously this is not a common problem but any hints would be appreciated. I'm open to any ideas. Could it be something simple like brake pads etc.? The wheel bearings appear good and the tires and wheels are nearly new. The front suspension was rebuilt a couple of years ago. I replaced the air cleaner element recently but I can't see how that would make this noise with air going through it at a higher load on the engine. I suspect that it is some odd thing that is taking place and I hope that someone has had this same problem.
