avoiding fender rubbing: a suspension design Question

My 66 bonneville has been heavily modified. The rear axle is a 10.5" 14 bolt FF and the front has 8-lug spindles from a 3/4 ton truck to match. The lower control arm was modified for the truck ball joint and I have temporary race-style tubular upper arms. The uppers would actually be just fine if I were confident that they were beefy enough but I'll probably end up fabricating some that will be better suited to the weight.

The front tires (225/65/16) match the original diameter but the truck spindles push them out about 3/4" - just enough that they rub the fenders in a turn. I also plan on going larger with the tires for weight concerns (this car is getting a duramax and will be used for towing up to 7000 lbs occasionally).

This also got me thinking about modern cars, particularly German cars that have tires that are almost flush with the fenders and they don't rub. I always assumed that it was because they found a way to modify the kingpin axis so that the arc of the tire's turn doesn't push it out while steering.

My Bonneville in stock form:

And my Bonneville with the truck spindles:

I think the look with the truck spindles is perfect, but I can't have it rubbing fenders.

What is the "correct" way to fix this? Do I need to select longer control arms and then use a spindle knuckle that doesn't protrude as far out?

first thought.... change wheel offset?

Second thought, roll the fenders?

fasted58 wrote: first thought.... change wheel offset?

I can do that, but one of the reasons I want to change the arc of travel is to keep the current look. I can always use more offset to suck the tires in but then it wouldn't keep the look I've created.

I can't help but think that there is some parameter about the geometry that can change how the tire moves during steering.

BITD, NASCAR pit crews kept a baseball bat in its tool kits for just such an occasion.

roll the fenders ?

edit: someone beat me to it

Lowere the inner pivot point of the upper comtrol arm gives more camber gain, might help. When do the tires rub, bounce, turn or both. Fender flairs are awsome. Work the fenders out for more clearance. Reduce the amount of wheel travel. I've rn out of ideas.

Wheel travel won't help. It rubs simply when turning. Therefore camber gain won't help either.

Double check me on this statement... isn't it true that increased kingpin axis provides camber gain when turning both directions, and increased caster angle provides camber gain when forward in the arc, and camber loss when rearward in the arc?

Basically, increasing kingpin makes the camber tilt in when steering both ways, and caster makes it tilt in when the tire moves forward in the arc, and outward when it swings backward in the arc. Is that correct?

Trying to remember my Milliken

Sounds about right.