Wheel offset

So, I keep seeing people comparing wheel offset as if it is the only variable in the equation. Commonly it is Pro wheels vs TRD OR wheels (+4mm for Pro's vs +15mm for OR).

The other variable is wheel width. The Pro wheels may differ by 11mm but the wheel width is also 0.5" less. So going with the Pro wheels only pushes the outer face of the wheel out by 5mm, not 11. 0.20" vs 0.43". Not a huge difference but still a difference.

The other place I see it is with aftermarket wheels. Offset is 0. Sure but the wheel is also wider so you're pushing it out 15mm plus half the difference of the width. The outer face of an 8.5" wide wheel at 0mm offset is gonna be 27.7mm farther out than that OR wheel, the outer face of a 9" wide wheel at 0mm offset is gonna be 34mm farther out.

Yeah, offset matters but without discussing wheel width, the offset only tells part of the story.

 

Yep. You got it. Whenever I consider offset I always have to draw a sketch to keep it straight. Another factor is the tire profile.

Interesting observation about the outer edge of the pro wheel only moving outboard slightly. And yet it’s enough to necessitate that the fenders get cut at the port.

 

I don't know, it seems the *tire* width at its maximum is going to be the same whether the wheel width is 7" or 7.5", in other words the amount of apparent poke is going to be mostly a factor of offset and it's valid to use it as the primary variable. Think if it as the tire bead is moving in or out a little bit while the maximum width of the tire midway between the rim and the tread stays the same.

 

OK, I can see where you're going and I had not thought of it that way. The tread width should be pretty static regardless of wheel width (I do believe the maximum tire width would change a little depending on the width of the wheel). I was too focused on the wheel aspect and not the tire.

 

Wheel width can be a more of an issue on some cars than others. On Type 1 VW’s (I made that infographic for fellow Thing owners) wider rims can rub the inside edge against suspension components. That doesn’t seem to be a factor on 4Runners.

 

Just to add to the convo. I found this site to be very helpful.