Challenge for the smart people

Technical Question and Answer - On topic to 71-74 Plymouth B-bodies only.

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NCbluebird
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Challenge for the smart people

Post by NCbluebird » Mon Dec 07, 2009 11:38 pm

LOL now that I have your interest.......

I want to tuck my rear tires into the fenders and keep the fatties I have. Part of the problem is the previous owner put American Racing Outlaw II milled 15" wheels on but with incorrect backspacing on the rear, hence they stick out a bit and the rear was lifted, first with Gabriels and then one stopped working, instead of fixing or replacing they stuck a set of coils ontop of the rear end to the frame, crazy I know.

Well I bought a new set of Gabriel Air shocks to install, I want to get rid of the coils and I'd like to bring the rear down a bit, but don't want to buy all new wheels. I'm currently running 275/60 -15 , they're brand new. What I need is to see if anyone can locate a pair of American Racing Outlaw II milled wheels that will fit right and let me tuck those tires inside the fender so I can bring it down a bit

Anyone up for the challenge???

lol

steved
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Re: Challenge for the smart people

Post by steved » Tue Dec 08, 2009 1:30 pm

are some rear ends narrower? maybe grab one of those? now you're buying a rear end, not a set of wheels...

Can someone chime in with drum to drum measurements, on what I presume is an 8 3/4 rear?

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Re: Challenge for the smart people

Post by 72RDRNR » Tue Dec 08, 2009 2:40 pm

From what I have been told by different tire professionals 275 tires need atleast a 9" rim (atleast for 17" rim with 40 series tires). If that same holds true for the 15" rim then you would have to step up to a 10" wide since they don't make a 15x9 in that style. The problem with the 10" wide is the offset is -38 and a couple of sites say that is too much. So I would maybe try talking to someone at American Racing or some retailer that has some experience with our older cars. Now I just saw that the only backspacing available on the 15x8 is 3.75" I dont think that will be enough to get them to tuck under, probably what you have on there right now. I hate to say it but from the 30 min I just spent looking (not very long so maybe I am wrong)I don't think it is going to work with those rims. The more I look the 15x10 only have 4" BS and I dont know if that will be enough either.

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Re: Challenge for the smart people

Post by NCbluebird » Tue Dec 08, 2009 3:30 pm

yeah I think honestly I'm going to be stuck finding another set of rims altogether. Hopefully I can use the tires, they're brand new

So, how about this, what recommendations from the site do I get for a Petty Blue with black strobes RR for wheels and keeping in mind I'd like to move the current tires within the fenders. Torq Thrust II with black centers, polished rim? Polished Torqs? or something completely diff.

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Re: Challenge for the smart people

Post by 71440 gtx » Tue Dec 08, 2009 3:44 pm

72RDRNR wrote:From what I have been told by different tire professionals 275 tires need atleast a 9" rim (atleast for 17" rim with 40 series tires). If that same holds true for the 15" rim then you would have to step up to a 10" wide since they don't make a 15x9 in that style. The problem with the 10" wide is the offset is -38 and a couple of sites say that is too much. So I would maybe try talking to someone at American Racing or some retailer that has some experience with our older cars. Now I just saw that the only backspacing available on the 15x8 is 3.75" I dont think that will be enough to get them to tuck under, probably what you have on there right now. I hate to say it but from the 30 min I just spent looking (not very long so maybe I am wrong)I don't think it is going to work with those rims. The more I look the 15x10 only have 4" BS and I dont know if that will be enough either.

mmmmmmmmmm i have on my 71 gtx 275 60 15 on 15 x 7 ralley wheels so why do i need a 9 rim for 275 60 15 :shock:
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Re: Challenge for the smart people

Post by NCbluebird » Wed Dec 09, 2009 11:44 am

Ok another question while contemplating a new set of wheels and tires.

I have confirmed with talking to American Racing that I cannot get a set of Outlaw II wheels in 15x8 or 7 with more than 4" backspacing, so my original intention of just replacing the rear wheels with one of greater backspacing is not gonna happen. I will need to do a full 4 wheel replacement. But I do want to stay with the 15" so I can re-use my current tires.

Since I'm running 275-60x15 in the rear I was thinking a 15x8 with 4.5 backspacing, what about the offset????

and up front presents another query, currently I am seeing people say to use 15x7 with 3.75" backspacing, but is that with drums up front or discs? I have drums now and will be installing a disc kit in a couple weeks, does that change the backspacing consideration? and what offset?

I'm looking at some cragar SS wheels for the period correct look. But I certainly could be pursueded to look at some BOSS 338 in 17s or 18s as well <wink wink>

B

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Re: Challenge for the smart people

Post by steved » Wed Dec 09, 2009 1:17 pm

the new cragar eliminators!! they're stunning and 160 bucks a pop for 17's. eventually that's the way I'm going...gonna enjoy my police rallyes for now.

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Re: Challenge for the smart people

Post by ffej » Wed Dec 09, 2009 5:40 pm

you could get a spring relocation kit. on my 72 ive got 15x10 weld prostars with mickey thompson 29x12.5x15 tires and they tuck up under the rear wheelwells really nice.just a thought :) ,jeff
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Re: Challenge for the smart people

Post by Elvad » Thu Dec 10, 2009 6:36 pm

The correct rear end for our cars is 2 inches wider than other B-bodys it is an E-body rear end width. You could do that, an A-body is even narrower but very rare.

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Re: Challenge for the smart people

Post by 71440 gtx » Thu Dec 10, 2009 8:02 pm

Elvad wrote:The correct rear end for our cars is 2 inches wider than other B-bodys it is an E-body rear end width. You could do that, an A-body is even narrower but very rare.
a e-body is 60 ins a 71-74 b-body 62 ins
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Re: Challenge for the smart people

Post by 72RDRNR » Fri Dec 11, 2009 3:40 pm

71440 gtx wrote:
72RDRNR wrote:From what I have been told by different tire professionals 275 tires need atleast a 9" rim (atleast for 17" rim with 40 series tires). If that same holds true for the 15" rim ...

mmmmmmmmmm i have on my 71 gtx 275 60 15 on 15 x 7 ralley wheels so why do i need a 9 rim for 275 60 15 :shock:
I guess the same does not hold true for the 60 series tires, BFG reccomend a 7.5-9.5" rim. So I guess a better response would have been to check out the tire mfg site and see what they reccomend. Not knowing what tires you have I just went to BFG and found this for an example. Most of the tire mfg sites I have seen have similar info.
http://www.bfgoodrichtires.com/specs/radial-t-a/12.html

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Re: Challenge for the smart people

Post by NCbluebird » Fri Dec 11, 2009 4:21 pm

So I was able to locate a matching set of American Racing Outlaw II wheels to match the front set in

16x8 5-4.5 bolt 0 offset and 4.5" backspacing

So I would need to also pick up a set of 16in tires, should I stick with the 275-60 series or what? This backspacing should get me inside the fender with the 275-50 size, would 295-50s put me back outside the fender?

Bill

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Re: Challenge for the smart people

Post by 72RDRNR » Fri Dec 11, 2009 11:54 pm

I will go out and measure mine this weekend for you. I will see how much backspacing I have and how much room on each side of tire. I will also see what my tread/sidewall widths are.

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Re: Challenge for the smart people

Post by NCbluebird » Tue Dec 15, 2009 4:17 pm

ok will a wheel with these specs fit inside the fenders???

Tire - 275-60R15
15x8 5/4.5
-5mm Offset,
4.25" Backspace

I've got a line on an excellent price, was going to pick up two of these for the back and the front will get:

Tire - 235-60R15
15x7 5/4.5
-6mm Offset,
3.75" Backspace

But I need to be sure they will tuck inside

Bill

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Re: Challenge for the smart people

Post by 72RDRNR » Tue Dec 15, 2009 11:36 pm

Just got mine measured:
My rim is a 17x9 with 5" backspacing. Don't know offset
Tires are 275/40 --- sidewall to sidewall it is just about 11" wide.
Outside of tire just clears the lip on quarters, inside there is 1 3/4" between tire and leafs.

Will yours fit?? I am thinking it will. But I would see what some of these others say (ie...71440GTX)
that have the smaller rims and larger sidewalls. Just from the rim measurements you will have little less rim on the outside than I do and that will be good.

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