I need help boys. I found a sweet set of rims i want bad, but theyre a 4.5 bolt pattern, so i know i will be needing an adapter. These wheels are 18x9 fr. and 18x10 Rr. It says the offset is plus 40 , I dont understnad offset but i think its differnet than backspacing. The wheel add doesnt say what the backspace is but i assume about 6.5 to 7.0 inches. Will 2inch adapters make these wheels fit?

yes you need to go to adaptitusa.com and get adapters that will work. Ebay typically only sells 4.75 to 4.75 bolt pattern adapters but the previous website has anything you need.

If it were me (I did calculations), i would go with 2" thick adapt up front and 1.5" out back. It gives you a rear backspacing of 5.08" and a front backspacing of around 4.08"...It will tuck the rears the best you can w/o rubbing and keep the fronts from rubbing.

GL

I am running 18x8.5 up front and 19x9.5 out back with wheels with 35mm of offset...my front backspacing is around 4.13" and my rear is 5.13" So youre pretty close to my specs...I also ran a 1.5" spacer up front and a 1" in the rear.

check my sig for pics or go https://www.thirdgen.org/forums/fire...t=#post3596593

I appreciate the input and i looked at your car and i love it . Another question i have is are you able to tell the backspacing by the offset number or is it completely different?

Zero Offset - The plane of the hub mounting surface is even with the centerline of the wheel.
Positive Offset - The plane of the hub mounting surface is shifted from the centerline toward the front or outside of the wheel. Positive offset wheels are generally found on front wheel drive cars and newer rear drive cars.
Negative Offset - The plane of the hub mounting surface is toward the back or brake side of the wheel's centerline.

I think offset is normal measured in Millimeters

yeah heres how i tell

25.4mm = 1inch
take a 10 inch wide wheel with a 35mm offset
35mm/25.4mm = 1.38 inches

so if the wheel was 0 offset then the middle would be 5 inches and you would have 5 inch of backspacing and frontspacing
HOWEVER, since there is a 35mm offset you add 1.38" to 5" and you have 6.38" of backspacing and then 3.62" of frontspacing

That makes total sense now , I appreciate that . So on a1.25 inch spacer would a 10 inch wheel be under or inside the wheel lip ? I guess i should say do you think it would look good? The wheel im lookig at is at wheelreplicas.com and its the FR5 in black, take a look and tell me what you think ,i would appreciate it .

aren't those wheels for a mustang? I was looking at the same website and loved those wheel but the 5x4.5 lug pattern threw me, maybe a spacer/adapter combo would remedy this, but that might be kind of a pain IMO