backspacing help

[Ci restorations]

Looking to buy wheels from someone they are 8.5x18 up front and 18x10 rear both with +25 offset. Will these fit a gn. Thanks for info ahead.

 

[Chuck Leeper]

both with +25 mil backspace

Huh??

 

[Ci restorations]

Huh??

?

 

[pacecarta]

i think he meant mm not mil

+ offset is deeper backspace pulling wheel in toward frame , - would push rim out
+25 mmthats +1" from CL
sounds like its a vette rim

on a 10" rim the cl is half the rim width (10.5") or 5.25 BS to center and then the offset of +25mm which is 1" additional puts the rear rims at 6.25" backspace
most trying to squeeze in a 10" rear rim would end up around 4.5 to 5" BS to get as close to the frame as possible ...those that dont hug the frame ...well those tires stick out and look like azz , i notched my frame to run a 10" wide 5" BS 275/60-15 mickey pro , without the notch it needed a 1" spacer
the answer is NO those wont work without an adapter , ideal without a frame notch for rear is around 4.5" and even that will vary from car to car depending on frame position , axle center and tire buldge over the rim and tire over height
stock height on the GN was 26.1"

8" rim with a 4" backspace fit pretty well front and rear and if your fronts are +25mm (9.0" rim cl is 4.5" +1" ) they will have 5.5" BS

 

[Ci restorations]

i think he meant mm not mil

+ offset is deeper backspace pulling wheel in toward frame , - would push rim out
+25 mmthats +1" from CL
sounds like its a vette rim

on a 10" rim the cl is half the rim width (10.5") or 5.25 BS to center and then the offset of +25mm which is 1" additional puts the rear rims at 6.25" backspace
most trying to squeeze in a 10" rear rim would end up around 4.5 to 5" BS to get as close to the frame as possible ...those that dont hug the frame ...well those tires stick out and look like azz , i notched my frame to run a 10" wide 5" BS 275/60-15 mickey pro , without the notch it needed a 1" spacer
the answer is NO those wont work without an adapter , ideal without a frame notch for rear is around 4.5" and even that will vary from car to car depending on frame position , axle center and tire buldge over the rim and tire over height
stock height on the GN was 26.1"

8" rim with a 4" backspace fit pretty well front and rear and if your fronts are +25mm (9.0" rim cl is 4.5" +1" ) they will have 5.5" BS

i think he meant mm not mil

+ offset is deeper backspace pulling wheel in toward frame , - would push rim out
+25 mmthats +1" from CL
sounds like its a vette rim

on a 10" rim the cl is half the rim width (10.5") or 5.25 BS to center and then the offset of +25mm which is 1" additional puts the rear rims at 6.25" backspace
most trying to squeeze in a 10" rear rim would end up around 4.5 to 5" BS to get as close to the frame as possible ...those that dont hug the frame ...well those tires stick out and look like azz , i notched my frame to run a 10" wide 5" BS 275/60-15 mickey pro , without the notch it needed a 1" spacer
the answer is NO those wont work without an adapter , ideal without a frame notch for rear is around 4.5" and even that will vary from car to car depending on frame position , axle center and tire buldge over the rim and tire over height
stock height on the GN was 26.1"

8" rim with a 4" backspace fit pretty well front and rear and if your fronts are +25mm (9.0" rim cl is 4.5" +1" ) they will have 5.5" BS

 

[Ci restorations]

Thats what i figured someone posted these for sale on here said they didnt need spacers but thats alot of backspace. Most Ive seen in 5.5 inch in the rear with a 10 inch wheel. What would good backspace be for 8.5 up front and 10 in rear?

 

[Ci restorations]

They were advertised as 25mm offset

 

[pacecarta]

if thats -25 than the rims are close to what you'd expect to fit a regal

 

[Ci restorations]

if thats -25 than the rims are close to what you'd expect to fit a regal

thank you