I understand that but a caliper 5 inches wide would be half an inch closer to fouling the spokes than a 4 inch wide caliper for example. Also less offset will generally bring the spokes further away from the mounting hub on a 1 piece wheel hence further from rotor and more clearance from caliper? Speaking specifically about Simmons fr1, so my question is, is anyone using these wheels on this car and is yes what offset is working on this exact combination.
The hub where it meets the rim base plate stays the same regardless of the caliper thickness and it's from the hub that the offset measurement is initially determined and moving the outer rim in and out from the base plate centreline changes the offset.
You can make adjustments to the base plate by shaving it to bring the rim and the centre spokes in closer to the brake caliper or add a spacer to the hub to move the centre spokes out further from the caliper but doing adjustment this way to clear brakes then impacts on the position of the inner and outer rim where it may foul the body and suspension.
It's still going to come down to how those centre spokes are designed and that's why you don't see many rims designed for modern cars fitted with big brake with a deep dish rims, they have the spokes to the outer edge with very thick base plates or like the japs who have centres that start in close to the base plate then curve out and back in again to give some dish while clearing the caliper, that's the centre design at work not the offset.
In saying that most rim centres should fit small standard calipers
You are not going to find many owners here running 22 inch rims and the best way to get accurate info is to contact the retailer or manufacturer for the specs on the rim, all good suppliers have this available then get out a tape measure and check for yourself to see if you have clearance around the calipers then make sure you know what tyre size you are intending to use and measure up where it will be in relation to your inner and outer guards.
Like it or not you are asking a question where the people supplying the product are the best people to seek your answers from and the more critical it is for you to get a close fitment to get the best look possible the more you need those specs.
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