Front end Bounce

I have a 65 Conv. W289 3 speed,my problem is at 45 mph the left front fender bounces up and down (I can see it from the driver seat) and I can feel it in the chassis. I have completely rebuilt the front end, new clutch and pressure plate, drive shaft balanced, NEW front brake drums turned and balanced, all 4 tires balanced several times tried a couple different sets of tires and wheels and the problem persists. It only happens at 45 mph, slower it goes away, faster it goes away. Any ideas? Could an export brace and or a monte carlo bar help to prevent this by stiffening up the front end? I know the front end is out of alignment, could that be the cause? what do you think

Ron
 
that is weird. is the fender attached to the bumper like it should be? I would get it aligned and see if that fixes it, it's something you should do anyway.

do you feel it more in the unibody or in the steering? It could be deathwobble, which is caused by too much toe in (or too little toe out), and not enough caster. Once deathwobble starts though you usually can't speed up to get rid of it.
 
I have a 2 piece export brace? 2 short pieces welded to the shock tower and then 2 pieces bolted to them and then they bolt to the front lip of the cowl. The other thing I have that I have never seen before are 2 long round bars going from the export brace mounting points at the cowl all the way forward to the forward most point of the inner fenders. I have never seen these on any 65/66 mustang that I have seen at numerous car shows.

Ron
 
Have you checked the bolt on the bottom side of the fender a couple inches in front of the door? If it has come off the fender will move in and out and appear to be bouncing at speed. Just something basic to check out. Hope it helps.
 
New Tires and I check that bolt it is tight. I can feel the bounce in the whole left fromt corner of the car. the type of bounce you would expect to see with a bad shock, however I just replaced them 2 weeks ago and it didn't help at all.

Ron
 
The other thing I have that I have never seen before are 2 long round bars going from the export brace mounting points at the cowl all the way forward to the forward most point of the inner fenders. I have never seen these on any 65/66 mustang that I have seen at numerous car shows.

Ron

Those extra bars are only on convertibles. They have to come off to use the export brace.
 
I have a 2 piece export brace? 2 short pieces welded to the shock tower and then 2 pieces bolted to them and then they bolt to the front lip of the cowl.

The two-piece setup is NOT an export brace, it's a flimsy thing sheetmetal item to reduce vibration. They are crap, and should be replaced on ANY Mustang except maybe trailered show cars that are never actually driven anywhere.

I have a 2 piece export brace? 2 short pieces welded to the shock tower and then 2 pieces bolted to them and then they bolt to the front lip of the cowl. The other thing I have that I have never seen before are 2 long round bars going from the export brace mounting points at the cowl all the way forward to the forward most point of the inner fenders. I have never seen these on any 65/66 mustang that I have seen at numerous car shows.

By the middle of 65 it was obvious to Ford that the convertible was shaky, so they added those two tubes to late 65 convertibles, and ALL 66 convertibles. Just using the export brace would have been better, but would have cost more. Cheapskates.

Use this:

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