66 Mustang, new tyres - rubbing on the guard

[FickleLife]

I have put 225/60/15 on the rear (no problems with clearance) and 205/60/15 on the front (problems with clearance). I'm experiencing some tyre rub on the fronts, on the drivers (RHD) guard. I have only driven the car 8km to so from the tyre fitting place to home however on that drive I experienced rubbing on the right guard on one left hand turn at a bit of speed (after which I drove slower around corners that I would have) and also on a driveway, again on the right guard. The previous tyres on the front were 185/75/14, the new tyres 205/60/15 are 20mm wider however the diameter of the new wheel is 6mm smaller if you use a tyre calc. It appears as if there are a few possible things happening here:

1) I have only noticed rubbing on front right, it appears the weight of the driver drops the car that bit lower. It is rubbing on the inner "lip" of the guard, an option would be rolling the front guards and hoping that would fix the problem. On the surface it appears that it would.
2) There's an interesting characteristic on the right hand (driver) side of the car. Both wheels front and rear on the right hand side appear to be 1-2cm closer to the inside of the guard than on the left hand side of the car. It wasn't apparent with the older 185 75 14 tyres but now the tyres are bigger you can see that they are closer to the guards on the right hand side with the naked eye. Why would this be the case?
3) Since it only seems to be the driver side of the car, could there be too much positive camber on the wheel? Would it be worth it to get an alignment?

If anyone could chime in with experience with this problem would be great. Thanks.

[boofhead]

It is important to know two points
1) The rim size (we know 15" but not the width) and very importantly the offset
2) A 66 does not have adjustable strut bars some owners change them to pull forward for more caster - are your caster bars stock?
3) Have you lowered the springs or are they sagging a lot?
4) Are you still using the standard mustang Spindles?

In any case, the tyre sizes should easily fit so it is a rim issue unless the front suspension alignment or car alignment is significantly out.

[FickleLife]

1) 15x7, all 4 corners
2 & 4) The car was converted from a 6cyl and has falcon discs and stubs (unsure which ones), I'll have to inspect the caster bars
3) I don't believe the springs are sagging...

I think I'll roll the guards and see what difference that makes. I have read people having to roll with 205/60/15 tyres.

[teacherspet]

I have the same problem. I put some 7" wheels with 205/60-15 T/A's, lowered the front with a set of King's springs & the tyres just catch the tops of the guards. I have decided to get both front & rear guards rolled (the rears have 8" wheels with 235/60-15 T/A's) but it is worth it just for the lowered look.

[boofhead]

I think it is two factors in play here;
1) Falcon stubs push the rim further out compared to the factory stubs   and
2) The common offsets used (3.5" [some are 4"] on a 7" rim) would not be enough to bring the wheel back to factory width.

Roll the guards is the easy approach at this point.

BTW: Did you get the Stubs modified to match the 66 steering points to remove the extra bump steer they add into the geometry?

[FickleLife]

Thanks teachers pet and boofhead

1) I did notice after the disc brake conversion the wheels were closer to the guards
2) The rims are 3.5" and they definitely stick out further than the stock 14 inch rims

The disc conversion was done some 15 years ago, I haven't driven the car for ~10 years (been overseas), can't remember exactly what was done on the front end but there is no bump steer. The steering geometry feels spot on, a bit of play in the steering box but over time XF power steering will go on and solve that.

[shaunp]

Unless the steering arms have been bent on the Falcon stubs it will have bump steer,  I can guarantee it no question. Jack it up and see if the wheels point in at awkward angles. An xf box can only replace a XA-XF manual box, if it has an earlier falcon box you'll need to bend the drag link.