well i am finally getting ready to throw down some cash at some wheels i have been drooling over. So now i have some questions. I thought i had all this undercontrol untill today when number just werent adding up.
Here is my problem:
the wheels i am looking at are 18x8.5 and 18x9.5. these wheels come in a +20mm and a +35mm offset. Now i started thinking about what the backspacing would be on these wheels and which offset i need. I calculated it up for each wheel with a +20mm offset. The 8.5 = 5.038" BS and the 9.5 = 5.538" BS. I thought all this added up correctly untill i searched for a fr500 deep dish wheel's info to check my math. So now i am real confused because on a 18x10 fr500 wheel with a +22mm Offset it is a 6.38 backspacing. to me and the calculations i get would make the backspasing on this wheel at 5.867. why isn't this adding up?
Here is how i got my numbers for the fr500 wheel
Take the centerline of the 18x10 wheel which = 5"
now add the offset which is 22mm = .867" which added to the 5 is 5.867 total backspacing. How do they end up with 6.38?
Here is my problem:
the wheels i am looking at are 18x8.5 and 18x9.5. these wheels come in a +20mm and a +35mm offset. Now i started thinking about what the backspacing would be on these wheels and which offset i need. I calculated it up for each wheel with a +20mm offset. The 8.5 = 5.038" BS and the 9.5 = 5.538" BS. I thought all this added up correctly untill i searched for a fr500 deep dish wheel's info to check my math. So now i am real confused because on a 18x10 fr500 wheel with a +22mm Offset it is a 6.38 backspacing. to me and the calculations i get would make the backspasing on this wheel at 5.867. why isn't this adding up?
Here is how i got my numbers for the fr500 wheel
Take the centerline of the 18x10 wheel which = 5"
now add the offset which is 22mm = .867" which added to the 5 is 5.867 total backspacing. How do they end up with 6.38?