Offset shackels

[Yellow Submarine]

 
Like many here I am trying to figure out tire and wheel size along with brake and suspension mods as necessary. I'm pretty much set on 15" rally wheels and Goodrich T/As. I temporarily have a very nice original Ford stamped set of Magnum 500 14X7" wheels with 30+ yr old T/A 235 14" tires on it now and am figuring future tire sizes based on these.
I considered using them but really want Ralleys in 15".
Ok, for the front I think 235s will be good. The rears are making me nuts. Thinking 275 60s or maybe 295 50s. From what I have read 295s will fit 8" wheels but will require offset shackles. Do offset shackles require re-positioning the spring pad on the e body axle housing? Are 295 50s really ok on 8" wide wheels?
 Please give my your experiences and thoughts.
John

[shawge]

When I went the offset route, I used offset shackles, offset hangers, and an axle with the correct spring perch locations (or get them repositioned.)

[dodj]

Spring perches will have to be re-positioned. Not a tough job, but educate yourself on drive line angles so you get them in the right spot. It can get confusing.

[1 Wild R/T]

Typically the trick is use the 1" offset hangers, use a B body housing & axles.. It drops right on the perches, the pinion angle is already set.. The B body housing & axles are 1.5" narrower than the E body axle so you gain 1/4" on the spring to wheel & 3/4" between the wheel & the outer wheel well....

[HP2]

Just stick with 275s and don't mess with changing up the suspension. Its much easier.

[69CHARGERMD]

"Typically the trick is use the 1" offset hangers, use a B body housing & axles.. It drops right on the perches, the pinion angle is already set.. The B body housing & axles are 1.5" narrower than the E body axle so you gain 1/4" on the spring to wheel & 3/4" between the wheel & the outer wheel well.... "

This is what I did,,but I was starting from scratch and needed a rear end, springs, etc.  295/65/15 now fits perfect.

[dodj]

I used the 1.5" offset shackles so moving the perches was necessary. I also added offset front hangers. Allowed me to fit 315's in the added room!

[Yellow Submarine]

Thanks everyone, very helpful. I think for now I will go with 275s. I will keep my eyes open for a good deal on a b axle housing for down the road
John

[HP2]

other bits of info for consideration...

Using the B housing only minimizes welding and changes the required wheel backspace. It does not create more room.

Offsetting the spring 1" will require new mounting pads on the E body housing.  Offsetting the spring 1" allows use of a B body housing without changing mounting pads.

Using the E body housing will require .5" to 1" (the most commonly found differences) more backspace on the wheel than using the B body housing.

However, B body housings are not all identical in width. They vary slightly. IIRC, the groups are 62-64, 65, 66-67, 68-70, 71-79.  Depending on which one you use, they may require relocating  spring pads and use differing wheel offsets. The 66-70 era  are the most commonly used housings for the E body swap that do not require moving the pads, but the 66-67 housing require .5" less backspace than the 68-70 versions. 71-79 versions are actually wider than E body housings so they will require up to 1" more backspace than using an E body housing.

Once the springs are out of the way, a Challenger can hold a 335 tire before the frame rails become the limiting factor.

295 will fit an 8" rim, but will require lower tire pressure to get full tread contact.  295 on a 10" rim  may require a bit more  pressure to equalize tread contact.

[Yellow Submarine]

Thanks HP 2 . That answers a few more questions I had. For every thing you change on a car 3 more are necessary.