13'GT Black

1. What cause factory rear axle offset? Does that mean phb chassis mount has different measurement in every mustang?

2. Im getting a thump noise that i also can feel sometimes in the rear when i accelerate quickly and let go of gas. Is this normal? 13' GT Auto

3. Im thinking about getting roush phase 2, what type of upgrades should i also get to put the power down or before installing supercharger? The only mod i have right now is whiteline adj. phb that i used to correct my offset and i can definitely tell it firm up the rear and handling a bit. Will all the upgrades make my ride harsh?

13'GT Black

bump
no experience/knowledgeable owners out there?

Van217

Factory rear axle offset... I believe you're talking about the rear axle being centered underneath the car. I would assume that the pan hard bar mount on the chassis from the factory would be the same on all mustangs. If not then they would have to come with adjustable pan hard bars or adjustable mounts. Just an adjustable pan hard bar would not firm up the handling a bit unless the car already had lowering springs or suspension work done to it. A stock suspension set up would not require an adjustable phb nor would one really have any effect on the stock set up. why was the axle not centered in the first place? That would be my main concern.

The thump noise you hear and feel could be your two piece drive shaft taking up slack within its joints when you let off of the gas.

As for the supercharger I do not have one but have done research and as far as I can see its pretty much bolt on ( with some serious mechanical talent) and is safe on stock engines. If your serious about that much power then suspension might be something to look into in order to put that much power to the ground. And with suspension work to put the power down your ride will be harsher. How harsh depends on the suspension you pick. I chose to go with the entire Roush set up. Lowered about an inch all the way around, tight handling, no more dive or squat, and just a slightly rougher ride than stock but not bad at all for the long rides.

CMcNam

1.) How much is it off? I imagine there is some differences in each car coming out of the factory. I wouldn't stress it too much unless it's really off (.25-.5" maybe). Since you already have an adjustable PHB you can just use that to correct it.

2.) Concur with the driveshaft conclusion, but unless we can get some more details it's hard to say. A video might help.

3.) You won't really need anything to supplement it and the panhard bar won't have that much of a noticeable impact on the ride so that might just be a placebo effect you're feeling. However, if you do find yourself lacking traction (I imagine you might) I would always start with stickier tires and perhaps a better set of rear lower control arms (think bushings here, the factory bushings are soft for a comfortable ride but don't help traction any).

I will caveat that you shouldn't make any modifications unless you really know what you need. It'll save you money in the long run, so if you do supercharge it get used to it first and then figure out what you need to make it better. It helps the learning process, something I wish I had thought about before I modified mine. My car is perfect for me now, but I know how hard the mod bug is to ignore!

jz78817

unlikely. there are tolerances allowed in body assembly, but in practice should only be +/- a few mm or else it would be difficult to actually build the car. Axle offset is usually only an issue if you change the ride height of the car; if you lower the car w/o changing the panhard bar the axle will move a bit towards the driver's side. A panhard bar swings in an arc and there is some side-side movement of the axle as it goes through its travel. an adjustable bar lets you account for that. Even better, a Watt's link eliminates that side-side movement but costs a lot more.

rjstubbl

I would contact someone like Brenspeed. They have supercharger kits that include everything required.

13'GT Black

I just find it wierd why everyones mustang rear axle have offsets, itching to know whats the reason behind it, most i seen or read online are around .1"-.5" off but mind was .65" off. Mine was considered alittle more than out of ordinary, i did read few(less than a hand full) online owners with offset greater than .5" with factory setup. PHB chassis is the only reason i could think of that can actually cause the rear to shift side to side with factory setup.

I was so worried i even took it to a frame shop to have the car measured, and everything was in spec......wierd. Now with whiteline adj phb installed, its truly centered now. Believe it or not whiteline adj phb did actually stiffens up the rear abit, i can feel it driving straight down the road or when corning on uneven roads. I can feel less movement in the rear lol.

Probably is the 2 piece driveshaft, gonna go for a one piece in the future.

@CMcNAM
that actually is a pretty good advice, i can go for the basic stuff like tires and brakes first and go from there.