Rim Fitment

*Jason94sport* · 06-09-2004, 02:45 PM

94 XLT stock suspension. 15X8 rims with a -30 offset. Will these fit the X? Would they stick out? I know I can use a 4", or 3.5" backspace. What is a
-30 offset in inches?

Thanks

*Jason94sport* · 06-10-2004, 04:54 PM

Bump

*X~FACTOR* · 06-10-2004, 05:37 PM

-1.18 inches

the_tool_man · 06-11-2004, 04:21 PM

Hi Jason94sport:

From your post, it appears that a few definitions are in order.

Offset is the distance between the wheel centerline and the mounting surface of the wheel. Increasing positive offset moves the centerline of the wheel out from the center of the vehicle. Said another way, positive offset puts the wheel mounting surface inboard of the wheel centerline. Many fwd vehicles use wheels with negative offset, which puts the wheel mounting surface outboard of the wheel centerline.

Backspacing is the distance between the wheel mounting surface and the inner wheel lip. Backspacing is always positive unless you are using wheels from a dually.

To make use of these terms, you have to also know the width of the wheel.

If you know any two, you can figure the other with the following:

offset = (width / 2) - backspacing
backspacing = (width / 2) - offset
width = 2 * (backspacing + offset)

Note that width and backspace are usually given in inches, and offset in millimeters, so you also need:

1 inch - 25.4 millimeters

When comparing wheels, two wheels with the same backspacing will have the same clearance to suspension components (assuming the same wheel diameter), regardless of width or offset. Two wheels with the same offset will load the wheel bearings similarly and not change the suspension geometry (assuming the same tire diameter), regardless of width or backspacing. Two wheels with the same width can run the same width tire (assuming the same wheel diameter), regardless of backspacing or offset.

I hope this helps.

Regards,
John.

*Jason94sport* · 06-14-2004, 08:11 AM

I'm just looking at new rims,& the only spec they have are 15X8 4.5" bolt pattern &
-30MM offset. I always thought offset & backspacing were the same thing. Just expressed different. So by your post the backspacing would be:
8/2 = 4 -offset which is -30mm

& 1' = 25.4mm so the backspacing would be somewhere around 3"?

Is that right?

*karl_burns* · 06-14-2004, 09:36 AM

Don't mean to hijack, but what are the specs I should look for? I've currently got som A/R Nitro wheels 15x8. Can any 15x8 wheels replace them? Or only ones with specific backspacing? Can I figure out the backspacing without taking the wheels off to measure?

The ones I found are 5 on 5? Is that OK? Is that 5" of backspacing?

Jason,
Did you get a new job? I know you were looking last fall. How's the sub? Still working all right? I've already gone through a voice coil on my 10w6!

Karl

*Jason94sport* · 06-14-2004, 10:21 AM

Yeah got a new job. All is good. I sold the sport last year. I just got a lightly used 94 XLT to hual stuff in. Can't fit much in my small 2 door Acura.

06-09-2004, 02:45 PM	#1
Jason94sport Elite Explorer South FL 93 Sport 2WD 5 speed Join Date: Apr 2001 Posts: 3,469 Vehicle Specs (Original Poster)	Rim Fitment 94 XLT stock suspension. 15X8 rims with a -30 offset. Will these fit the X? Would they stick out? I know I can use a 4", or 3.5" backspace. What is a -30 offset in inches? Thanks

06-10-2004, 05:37 PM	#3
X~FACTOR Name is Ray Valley Stream, Long Island '97 XLT 4-dr SOHC Join Date: Jan 2003 Posts: 6,729 Vehicle Specs	-1.18 inches __________________ My Mods

06-14-2004, 09:36 AM	#6
karl_burns Elite Explorer Winston Salem, NC - Go Deacs! 98 Sport OHV 5speed Join Date: Nov 2000 Posts: 1,196 Vehicle Specs	I have the exact same question! Don't mean to hijack, but what are the specs I should look for? I've currently got som A/R Nitro wheels 15x8. Can any 15x8 wheels replace them? Or only ones with specific backspacing? Can I figure out the backspacing without taking the wheels off to measure? The ones I found are 5 on 5? Is that OK? Is that 5" of backspacing? Jason, Did you get a new job? I know you were looking last fall. How's the sub? Still working all right? I've already gone through a voice coil on my 10w6! Karl __________________ Karl Burns 2000 Explorer Sport: KKM, BBK 66mm TB, Granatelli 70mm MAF, 3" Intake, 31" BFG AT/KOs 1998 Explorer Sport: Spindle Lift, SOA, Rancho 9000s, powered by Apten, PIAA 1500s and 520s Eclipse, McIntosh, Focal and JL sound system

06-10-2004, 04:54 PM	#2
Jason94sport Elite Explorer South FL 93 Sport 2WD 5 speed Join Date: Apr 2001 Posts: 3,469 Vehicle Specs (Original Poster)	Bump

06-11-2004, 04:21 PM	#4
the_tool_man Wannabe Elite Explorer Spartanburg, SC '01 Sport 4x4 Join Date: Jun 2002 Posts: 310 Vehicle Specs	Hi Jason94sport: From your post, it appears that a few definitions are in order. Offset is the distance between the wheel centerline and the mounting surface of the wheel. Increasing positive offset moves the centerline of the wheel out from the center of the vehicle. Said another way, positive offset puts the wheel mounting surface inboard of the wheel centerline. Many fwd vehicles use wheels with negative offset, which puts the wheel mounting surface outboard of the wheel centerline. Backspacing is the distance between the wheel mounting surface and the inner wheel lip. Backspacing is always positive unless you are using wheels from a dually. To make use of these terms, you have to also know the width of the wheel. If you know any two, you can figure the other with the following: offset = (width / 2) - backspacing backspacing = (width / 2) - offset width = 2 * (backspacing + offset) Note that width and backspace are usually given in inches, and offset in millimeters, so you also need: 1 inch - 25.4 millimeters When comparing wheels, two wheels with the same backspacing will have the same clearance to suspension components (assuming the same wheel diameter), regardless of width or offset. Two wheels with the same offset will load the wheel bearings similarly and not change the suspension geometry (assuming the same tire diameter), regardless of width or backspacing. Two wheels with the same width can run the same width tire (assuming the same wheel diameter), regardless of backspacing or offset. I hope this helps. Regards, John.

06-14-2004, 08:11 AM	#5
Jason94sport Elite Explorer South FL 93 Sport 2WD 5 speed Join Date: Apr 2001 Posts: 3,469 Vehicle Specs (Original Poster)	I'm just looking at new rims,& the only spec they have are 15X8 4.5" bolt pattern & -30MM offset. I always thought offset & backspacing were the same thing. Just expressed different. So by your post the backspacing would be: 8/2 = 4 -offset which is -30mm & 1' = 25.4mm so the backspacing would be somewhere around 3"? Is that right?

06-14-2004, 10:21 AM	#7
Jason94sport Elite Explorer South FL 93 Sport 2WD 5 speed Join Date: Apr 2001 Posts: 3,469 Vehicle Specs (Original Poster)	Yeah got a new job. All is good. I sold the sport last year. I just got a lightly used 94 XLT to hual stuff in. Can't fit much in my small 2 door Acura.