I was looking at a set of replica alloys on discount tire's site and was wanting to know what would best fit my 06... I am wanting to go with a 9" rim on the rear and it shows offset of 45 c and was wanting to use a 8" on front and they have 2 to pick from ...one is listed as 30c and other is 29.5 hc 29.5 ?? is the 29.5 hub centric?? if so I am guessing I would pick up 1/2 inch to the outside and inside over factory rim?? Would the 45c be the same stickout as factory rim??? I would not mind picking up about a 1/2 or so past foctory but do not want my tires outside fenderwells ..Thank you for any help...oh these are the 17" replica alloys

 

Beware of some of the discount wheel shops on the internet!! The '05/'06 GT takes a specific wheel offset that is unique to this model year. There is a shop that I am currently in arbitration with that is advertising 17X8" Bullitts for the '05/'06 Mustang that are actually '94-'04 wheels they are claiming, "fits the '05 perfectly".

Yea, if you want your stock tires to stick out an additional .500" that is [:@]

 

Bush,

I'm a bit confused by your post. Offset is measured in mm, not "c"s or "hc"s, and as far as I know, whether or not a wheel is hub centric or not has no bearing on offset. [sm=dontgetit.gif]

Anyway, as rotorr points out, the last gen had very different offset (in the +25mm range), this gen is in the +45-50mm range. Stock 18x8.5" rims have +50mm (Ford cast the specs in the back of one of the bullit spokes, you can verify with a mirror and flashlight). The lower the offset figure the more they will stick out towards the fender. Some folks are running just under a +40mm offset here, but I think that's at the extreme of what you want to do.

Oh, there are wheel/tire calculators you can find online that are useful for getting a sense of what effect a given combo change will have on your ride. I like: http://gs.tolan-hoechst.com/tirecalc.htm

Best,
-j

 

The following I wrote in another thread. It should answer your questions. If not just hollar.

An inch is about 25mm. But here's a conv chart:
http://www.voltplastics.com/in_mm.html

Great info on offset and backspacing at:
http://www.rsracing.com/tech-wheel.html

In there you'll see as they say: Rear spacing or back spacing is the distance from the backside of the wheel mounting pad to the outside of the rim flange. The offset is the distance from the centerline of the wheel to the mounting surface of the wheel.

Anyway the stock bullit has 6.295" backspacing and a positive offset of 45mm. (Positive offset: When the back of the wheel mounting pad is closer to the street side of the wheel; here the mounting surface is outboard of the rim centerline.

If for example you used 10" rims with the same 45mm offset (mounting face in same relative postion to centerline as the stock bullit rim) then with the two inch greater rim width you are putting 1 inch more outward of your wheel mounting pad and 1 inch more inward of your wheel mounting pad. Now if you only had a 20mm offset for example that 25mm less (approx 1 inch) will be all outward movement of the rim position (just like you had thrown a 1 inch spacer on there). Now you're out 2" which to me is not acceptable, at least looks wise. Because of a special paint scheme on my GT, and I see how debris already kicks up with stock setup I have gone with FRPP 17x8 chrome bullits. ...just don't want the tires outward anymore than stock; but that's me. Up to an inch seems reasonable I guess; up to you.

As far as the rims clearing the calipers that has to do with the spoke design and how it is built with respect to the bolt face. 05-06 GTs require more clearance than most so you have to know that the rims are proven test fit for the 05-06 GT or order one and test it (before mounting any tire) yourself. OEM bullits come incredibly close to the calipers.

Hope this helps. ...Jim

 

Thanks for the info . I thought it was strange that the site showed the offset in c's?? I was going to order over the net since we dont have a discount tire store where I live but took a trip out of town today and spoke to them in person . I am looking at the o.e bullits and the guy told me they had a 45mm offset on the 9" and I think he said 40mm on the 8" . I will be talking to him again monday morning to confirm this once he talks to who ever they order from

 

There are no OEM bullits (FOMOCO) in 9"; 17x8 and 18x8.5 both with 45mm offset. Just go to fordracing.com for info. Watch out for co's that say stuff like exact fit and correct offset (they lie; it's unreal)

 

I need to know info on replacing my 2000 mustang's wheel hubs. Can anyone help or direct me to info on this subject? Thank you very much.

-Ken

 

Thanks fairlane! Ugh, people keep saying OEM 18" bullit wheels are 9" wide--nope, 8.5"

Unfortunately, they are not 45mm offset, it's 50mm offset. The figures are cast into the wheel--I'm not making this up. You see "18x8.5 50mm" behind one of the spokes. I can take pics of it if you like.

OEM 17" wheels have a different offset, but it's not much (I think it effectively cancels out the 1/2" difference in wheel width).

kenco, go to the 4.6 Mustang section, I'm sure they can help you out. If the search function ever gets to working correctly, you might even be able to find the info yourself.

Best,
-j

 

The 2005 O E M 17" Bullits have a 45 mm offset
the # is cast in the back of the wheel.