Rear spring relocation kit

[CudaMoparRay]

What would be any possible problems with doing this or is it all gain?
Seems too simple to me. 

https://www.ebay.com/itm/70-74-E-Body-Mopar-Challenger-Cuda-Leaf-Spring-Re-Location-Kit-4-5-per-side/302202684325?hash=item465caf03a5%3Ag%3ACWoAAOSw2xRYg-QT&_sop=15&_sacat=0&_nkw=Plymouth+barracuda+mini+tub&_from=R40&rt=nc&LH_TitleDesc=0%7C0

[Katfish]

No issues, but you won't gain the whole 4.5" on the rim.
Your limited by the wheel housing size as to how much tire you can fit.

[kass_paul]

to me spring relocation kit has always meant something like this

https://tranio.com/usa/adt/1632457/
obviously need to educate myself 

[Brads70]

No issues, but you won't gain the whole 4.5" on the rim.
Your limited by the wheel housing size as to how much tire you can fit.

You will also need to do a "minitub" to make full use of the extra space created. In addition I think this mounts the springs parallel , which will not be helpful if optimum handling is a consideration.
The other issue is it's not so easy ( or cheap) to return to stock if you wanted to down the road. Offset spring mounts/shackles are a simple bolt on, this is more of a permanent modification to the chassis . 

[RUNCHARGER]

Yes: You will have to cut up the inners to make full use of it and rear springs that are closer together are going to lead to less stable handling. The B-body width relocation gives you a lot of room and is less evasive.

[1 Wild R/T]

Yes: You will have to cut up the inners to make full use of it and rear springs that are closer together are going to lead to less stable handling. The B-body width relocation gives you a lot of room and is less evasive.

No kidding.... If 13" isn't enough tire then you can look at that method.....DC was selling a kit for that clear back in the 70's , probably the 60's.... 

The normal offset kit is a bolt in deal, if someone wants to go back to stock they can..... This method is sort of a racer thing.... Reason I say "sort" is because it looks racer like but suspension technology has advanced well past just moving the springs inboard.....

[CudaMoparRay]

The responses seem to allude to the fact that this mini tub would have to be done also in order to get the full 15" clearance which made no sense to me originally because supposedly the first change (spring relocation) gave 4.5" so in my mind added together would be 19.5" on each side   

https://www.ebay.com/itm/70-74-MOPAR-E-Body-Challenger-Cuda-Mini-Tub-Kit-15-tire-clearance-run-355-30-19/302202676563?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3Df3abefe68c8f46ef8de86fea7f2b79c6%26pid%3D100675%26rk%3D2%26rkt%3D15%26sd%3D173399936208%26itm%3D302202676563&_trksid=p2481888.c100675.m4236&_trkparms=pageci%3A378a0615-9435-11e8-bd9d-74dbd180c337%7Cparentrq%3Aecd446911640aa14483b96b3ffec6e8b%7Ciid%3A1

Thank you all for the great technical information now looking at B-body rear instead like suggested.

[HP2]

FWIW, You don't need a B body rear to get extra room. The  first point of interference to wider tires are the springs. Move them in 1" per side and you can now fit as much rubber as the wheel tub is capable of taking without modification. 

The difference between doing this with an E body housing and a B body housing is that the B body housing drops right in on the relocated springs with no other mods. The E body housing will require removing the original spring mount pads and adding new spring mounting pads to the axle tube to line up with the new spring location.

The two different housing also will require different backspacing on the rims to achieve maximum rubber usage.

[1 Wild R/T]

FWIW, You don't need a B body rear to get extra room. The  first point of interference to wider tires are the springs. Move them in 1" per side and you can now fit as much rubber as the wheel tub is capable of taking without modification. 

The difference between doing this with an E body housing and a B body housing is that the B body housing drops right in on the relocated springs with no other mods. The E body housing will require removing the original spring mount pads and adding new spring mounting pads to the axle tube to line up with the new spring location.

The two different housing also will require different backspacing on the rims to achieve maximum rubber usage.

True.... But by using the B body axle your wheels wind up with a deeper offset & deeper looks much better.... Unless you prefer the "sleeper" look of a totally stock depth wheel from the side but plenty of meat from the rear....