defiance

I am looking at f14s deep concave, rear 20x11 +55 and 20x9 front with +35

Trying to make sure the wheels will be flush, no tucking or sticking out.

Any of you guys running this offset on 05-09s?

Cruzinaround

my offset on the Forgestars are 56mm for the rear 20x11's

and for the front it is 42 mm offset for 20x10's

They line up perfect. However...Getting the rear wheels on is tight. You will need to put a jack on the axle...or where the Shocks link to the axle to get the wheel on. If you put it on a lift with all the weight unsprung...You will not get the wheel to spin free as the outer part of the chassis where the Coil Spring pocket is tapers out and rubs the inner side of the wheel. But, this is only with all the weight unsprung and the axles fully extended well over 5 inches of travel...There's no Mustang going to experience this unless you plan on being airborne.

With a 55MM offset you might have an easier time of it on a lift. The odd thing was the 56mm offset was the original spec of this wheel option from AM. They may have changed it after I called them while my car was on a lift and sent them photos of what was happening. The Forgestars are pricey so they don't sell as much as the heavier AMR's that look similar.

They..(AM) told me these offsets were tested on their own vehicles and that the sizing is the same whether a v6, GT, Boss or GT500. That Said....these offsets were a bit tight getting them on for the rear. However, once the car is planted back down on earth...these offsets clear just fine.. they also clear aftermarket calipers...like Wilwoods front and rear.

Knowing AM prefers to side on caution they may have changed these measurements for these Forgestars in the year and a half since I purchased these wheels. Otherwise...I really have no complaints.

Just saying.

jRaskell

I've never planned on being airborne, but it has happened once and nearly happened on a few more occasions.

Norm Peterson

I think you're talking about the shipping tie-down attachment brackets that serve double-duty as reinforcement for the bump stops.

You can safely cut most of these brackets away, leaving a little at the bottom for the bump stop to use if you're retaining the OE bump stops or using OE-style aftermarket replacements. That is what I did for my 18 x 11 Forgestars. I also had to cut back the rear shock boots, though with 20's this might not be necessary.


With 11" wide rear wheels, you may need an adjustable-length PHB for its firmer bushings to keep from getting any rubbing during extremely hard cornering. Depending on tire size you may need to intentionally offset the axle a little as well - a PHB-controlled axle moves more during turns in one direction than it does for turns in the other.


Norm

gmoran1469

Or get a watt's link and forget about that problem.

Norm Peterson

Of course. But I also suspect that a Watts link might not be too high up on the list of desirable supporting mods in this particular instance where appearance seems to be the only concern (2" of wheel stagger, must be flush, etc.).


Norm

Cruzinaround

I wish that was it... Its actually the unibody-chassis at the points where the rear coil pockets are. But, really ... since the chassis wall here tapers in as you follow it up.... The wheel clears no problem. Its literally when the vehicle is unsprung and the axle hangs at the fullest extension. Then the inner lip of the wheel will rub on the chassis. enough to require you to muscle the wheel to spin it...But then you're chaffing the finish of the wheel, even if you can't see it. So the best bet is to put each wheel on one at a time... lifting the axle on each side and a jack stand right on it high enough to clear.... Then...you're good.

And on the hilly roads where i drive there are points where the suspension travel takes it up to this limit, but as far as I can tell...there is no rubbing.

Having the Watt's link is a plus. And the Airlift. Even with the bags fully extended like when I go down a really f'd up dirt road... there's still no rubbing, I can see the inner wheel lips are not rubbed to hell. So I'm good.

I just looked and see that AM now lists the rear offset for their 20x11's as 55mm offset which is tight but should be good with the axle unsprung on a lift. and they only have the 20x9's not the 20x10's for the staggered front wheel option. So I'm guessing they wanted to be safer than sorry? Although their 19's still come in 19x10's.

At least my front's offer a wider contact patch to compliment the rear width.

So Camaro-ish of me. ;-)


Just saying
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Norm Peterson

I think AM knows their customer base really, really well. Though it doesn't square very well with Ford running 9.5" wide wheel up front on several years of GT500 and substantial owner experience with GT500 wheels on "regular" GTs. Then again, there are many 18 x 8's to choose from, which are half an inch narrower than the OE 18's at least through 2008.




Can you get a picture of one rear wheelwell? The procedure you described for removing a rear wheel sounds an awful lot like what Terry Fair had to go through with 18 x 12 rear wheels before he amputated the tiedown brackets completely (drilled out a few spotwelds)


Norm

CMcNam

OP, give Howey at Howey Industries a call. I bought my Forgestars from him. Gave him a description of all my mods and he gave me a suggested offset. They fit exactly flush.

Cruzinaround

I absolutely agree with you.... AM even got on the phone with the shop steward to tell him the wheels will fit when they were swapping my tires etc etc....The shop refused to do the work even with AM confirming the fitment.

So i just took it home and did it myself after the shop mounted the tires.



I have the pics on my phone still I'll get them off and share them... They were taken in the tire shop while AM was on speakerphone with them....

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