Compatible Tire and Wheel Recommendations
Converting to a front-steer rack and pinion system does come with a few compromises. In order for steering geometry to be correct, steering arms are closer to the wheel than rear steer. In addition, it's usually desired to have the ride height lower to the ground, putting the front tires further up into the wheelwells and closer to the fenders when turning.
In front, track width is dependent on the brake kit used and can vary 3/4" per side, so wheel backspacing must be determined after choosing the brake kit, or different brake kits can be chosen to work with particular wheels you may want to run. One universal fact is that because the car will be lower, wheels require MORE backspacing to get them further inside the fenders so there will be ample tire clearance when turning. The next universal fact is that because the steering arm is further outboard, 15" wheels are limited in width and backspacing, even with the widest track brake kit available. On A-bodies you can run a 15"x 6" rim with a maximum of 3.75" of backspacing. Alternatively you can use 4" backspace with a 1/4" wheel spacer, or you can also fit a 15 x 6 with 3.5" backspace. On B and E bodies there's an extra inch of fender so the backspacing on 15" rims is the same but the width can be 7". The exception to this is 66-67 B-bodies, which have similar clearance requirements as the A-bodies.
16" wheels are not big enough to clear the tie rod end, so similar sizes are required.
17" wheels will clear the tie rod end, so you can go out to 8" wide and also fit the full range of available brake kits, so backspacing should be matched to the brake kit desired, or choose a brake kit that will allow a particualr wheel to fit. It's not recommended to go wider than 8" on a 17" rim because the rim edge can hit the tie rod when the wheels are fully turned.
On 18"+ wheels, they will not contact the tie rod, so you can go up to 9" wide in front, even on A-bodies. Again, backspacing is very important as you are taking up all the space available in the car and clearances become critical.
Tire sizes in front should be limited to a maximum of 26" diameter and 11" section width. You can use the tire size calculator tech page to convert metric sizes to inch measurements.
In the rear, using the street lynx in the stock mounting location will give you 3/4" extra clearance on the inside compared to a leaf spring. In addition, if you move the links inboard under the frame rail, you must widen the wheelwells in to the frame as well in order to take advantage of the extra space.
For a street car in the rear its wise to leave 1" of airspace on each side of the tire to prevent rubbing on uneven roads and intersections - when the car rolls over crooked streets, the tires camber in as they go up into the wheelwell, so this clearance is really needed to avoid rubbing on public roads. As an example of all this, if you have 14" of wheelwell, use a tire around 12-12.5". In a 15", this tire may be recommended for a 9" rim not a 10. In an 18" rim, a 12" tire may fit best on an 11" rim, and in 19 or 20 a 12" wide rim might be recommended.
Also worth noting in a musclecar is bigger tires look better than thin sidewall "rubber band" tires and the ride quality is also better. So in general use the minimum width rim for a particular tire so the tire appears bigger and fatter than it actually is. Curved wheel designs can also provide the proper backspacing while still allowing a wider lip on the wheel, further improving the musclecar look without sacrificing handling.
Small tricks can make all the difference to combine excellent handling with great looks.
As always, we are always happy to help with wheel and tire selections before you buy anything.