Wheels techincal information please! Sn95 vs S197 wheels

[Darhawk]

Helllo fellow Stangers,

I am wanting to know the reasons why S197 wheels need spacers or something like that to make them equivalent to sn95 wheels. What is the difference and problems related to running a S197 wheel on a 1994-2004 car? I would like a in depth answer so I can learn about this.

Can someone show me before and after pics of when they installed S197 wheels on their car and then what they did to make it flush with the fenders?

Please help me understand this and what all the offset talk is about.

 

[whiplash473]

from the silverado forum im on..that will explain offset for ya

http://www.fullsizechevy.com/forum/...terior-tech/76444-wheel-offset-explained.html

 

[Walking Tall]

If there is just a certain style you like then American muscle, latemodel and a few other places have S197 style wheels in the correct offset for our cars.

 

[Darhawk]

↑ That is true Walking tall. Believe me, I know wheels and where to get them. I just wanted to know more about the tech info.

 

[Mystic SVT]

This is an example:
Imagine the wheel displayed in the center is a 94-04 offset wheel, notice had the mounting area is aligned with the wheel center?
Now, a S197 wheel would be the one on the far left. Notice how the mounting flange surface has a positive offset. When you mount S197 wheels on SN95 chassis'd cars the wheels will tend to sit further in the wheelwell thus causing rubbing issues with the frame/suspension parts. This is why a spacer is needed to bring the wheel to a proper offset.

 

[Darhawk]

Thanks Mystic SVT for your post, that clears up that part for me.
Is there a point when the postive offest would too great and that a spacer would be too dangerous to drive with? What is the common offset of a SN95 car? Or at what point would the offsets for SN95s become postive?

Use this for example: If I bought these, how far in would these sit? Offset for these are 44 and a bolt pattern same as normal 5x114.3
http://www.ebay.com/itm/FORD-MUSTAN...Parts_Accessories&hash=item19d73dfd92&vxp=mtr

 

[Ninety8stang]

Thanks Mystic SVT for your post, that clears up that part for me.
Is there a point when the postive offest would too great and that a spacer would be too dangerous to drive with? What is the common offset of a SN95 car? Or at what point would the offsets for SN95s become postive?

Use this for example: If I bought these, how far in would these sit? Offset for these are 44 and a bolt pattern same as normal 5x114.3
http://www.ebay.com/itm/FORD-MUSTAN...Parts_Accessories&hash=item19d73dfd92&vxp=mtr

there is a point where a spacer can become dangerous to run and be really stressful on your rearend (bearings, studs, etc.) especially under high loads I.E launching. i ran a 1in spacer on my car for the longest time with no complications when i had my bullitts but i dont think i would really feel comfortable running anything larger than 1 1/4in. If you do run a spacer make sure its a hubcentric spacer as well.

 

[ProKiller]

if you really wanted to run them, do this:
http://www.vintagevenom.com/mustang-full-disc-brake-conversion-kit.htm

 

[Tony]

^yea if i went with s197 wheels id go that route. especially on you cobra hawk.

 

[Darhawk]

I already have spacers @1.25 inches on my rears, so the wheels sit flush with the fenders. http://www.americanmuscle.com/15in-billet-wheelspacers.html
They look like the link, but my were custom made.

So I have been noticing on AM that all the 1994-98 wheels have an offset around +22 through +29. Then I popped over to look at 05-10 wheels and the offset is like +44 to +50. So I guess the new S197 start to turn out bad for our cars around +40mm...I get that part now.

So does that mean with spacer on my rears at 1.25 that my offset has added to and changed by 32mm. Do I add the spacers with the current offset size to get my new offset size? Then based on that I will know what wheels will hit the edge of the fenders?

Or is that totally wrong?