What was the standard size of a oem police style rim? 15x? Thanks for your help
Police wheel Question?
- Thread starter sabre67
- Start date
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66340SEDAN
FABO Member #3649
They made a few different sizes depending on the year and model, but I’m guessing you are wondering about the common 15” slotted hole type used during the late 70’s-80’s? Those were all 15x7 and used a snap on hub cap
Thanks for your reply
Yep, 15 x 7 and yes they are Heavy, Heavy.
Lots of rotating mass to spin up there every time you take off and slow down.
Lots of rotating mass to spin up there every time you take off and slow down.
Thanks all, great help
Jarlaxle
Well-Known Member
What's the backspacing on the 18s? I want to swap my Duster from 14/15" Rallys to 17s, but am terrified of spending a pile of money and finding out that the wheels do not fit.
My 18x9’s have a +35mm offset, so that’s a 6.38” backspace. The DoctorDiff 13” brake kit I run adds about 5mm, so effective backspace compared to a 73+ mopar disk is about 6.2”.
With 17’s though you can’t go that deep, the outer tie rod end will hit the lip of the rim on a lot of 17” wheels if you go past about 5.7”. It depends on the design of the wheel, there are some that can do more but with 17” I wouldn’t go past 5.7”, which also means a 255 is about the widest you can safely go without significant fender mods
Jarlaxle
Well-Known Member
255 is fine-I was honestly thinking 225 or 235. (I know that 235/55R17 is a common tire size.)
So...17x7 should work...probably 5" backspacing...right? (Which is...what offset? Crap, I'm confused.)
So...17x7 should work...probably 5" backspacing...right? (Which is...what offset? Crap, I'm confused.)
So for a 235 in the front you’d have to run a 235/45/17, even a 235/50/17 is 26.3” tall which will be tough to clear in the front because of the height. For a 235/45/17 you’d need at least a 17x7.5, I’d just run a 17x8. You’d want 5.25” of backspace for that so you’d be looking at +18 for the offset, and anything up to 5.7” would be fine.
For a 225 you’d be looking at a 225/50/17, that would be 25.9” tall and would work on 17x7 and for a 5” backspace you’d be looking at a +25 offset.
For the rears I’d need to know what axle you’ve got
Jarlaxle
Well-Known Member
Norm.P
Well-Known Member
Does this apply to Darts as well?
They were 7" wide and the Super Coupes and Aspen R/Ts used a special 8" version.
Yes it does
Norm.P
Well-Known Member
Thanks Blu! If the size were 17x7 instead of 17x8, does the backspacing change?
It doesn’t have to, with a 17” rim ~5.7” remains the maximum. With a 17x8” about 5.25” is a good amount, so with 17x7 keeping the wheel in the same spot would be more like 4.75”. I wouldn’t run less than 4.25”, but since you’re going to be limited to nothing wider than a 225 on that 17x7 even up to 4.25” of backspace would work.
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