18" wheels

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Broken & bent rims?
I drive 30-35k miles a year and have always have wide low profile tires on my cars, even in the winter, for the past 25 years. (We are talking less the 2" side wall). I've never broke or bent a rim here in Michigan.

Exactly. Millions and millions of late model cars have 18" or larger rims.

California ranks around 7th for worst roads in the country. They suck, we never do road maintenance. I've broken suspension parts, but not rims. So yeah, I'm not worried about it.

IMO 18's are too big for an ''A'' body, 16's are the biggest I would use. But I am not that young anymore.

Too bad you can't find a decent tire compound in anything less than 17". And I'm not talking race tires, I mean DOT legal street tires in the right width and profile for an A body set up for handling. I don't give a crap what it looks like, it's about function. I prefer 17's, but you can't run 275's up front on an A body with 17's without major fender surgery or a tie rod end-ectomy. And it makes running 13" brake rotors a piece of cake. And they don't suck either.
 
Well it's good to know Flint is in better shape than Chicago!

As far as what rims and tires people like... everybody is different. Some people still like ugly *** Keystone 14" rims that stick out of the fenders and think that it looks right. Others think 18" rims look great and are the way to get performance, looks, handling and women. Giggady Giggady!
 
What would some have to do in order to get the same offset/backspacing on all four wheels? I imagine you would have to adjust the width of the rear-end to work with the front since there is only so much wiggle room to play with up there in front.
 
Correct, you have to change the width of the rear axle. And it depends on your spring location too, that changes what you need for rear end width.

If you have a 1/2 spring offset and stock tubs The closest fit to match the offsets front and rear with wide rims is probably the 65-67 B body rear axle. I have a 68-70 B body rear in my duster and my front offset is 27 and the rear is 38. The 65-67 would be pretty close to even with the max width rims, a small spacer in the rear would make it perfect.

The other option is to just not max out the front tire width. If you stick to an 8" wide rim and 245's you can run a 5.25" backspace all around. With a 1/2" offset you wouldn't need a spacer in the back, with the stock spring locations you'd need a spacer.
 
Correct, you have to change the width of the rear axle. And it depends on your spring location too, that changes what you need for rear end width.

If you have a 1/2 spring offset and stock tubs The closest fit to match the offsets front and rear with wide rims is probably the 65-67 B body rear axle. I have a 68-70 B body rear in my duster and my front offset is 27 and the rear is 38. The 65-67 would be pretty close to even with the max width rims, a small spacer in the rear would make it perfect.

The other option is to just not max out the front tire width. If you stick to an 8" wide rim and 245's you can run a 5.25" backspace all around. With a 1/2" offset you wouldn't need a spacer in the back, with the stock spring locations you'd need a spacer.

My idea is to get a matching set of four so I can rotate them all. I am going to relocate the rear leafs, with stock tubs. so that won't be an issue. I assume it would be possible if one were to get a longer housing and cut that down to the exact length needed to fit the front spec wheels.
 
Just to be clear, those of you with 18x9's on the front, say it is easier To get a 9 wide with an 18 than a 17?

Just saw a valiant at the show this Sunday with 18x9s with 285's on it! I think it was "tomswheels" old car...? Purple valiant.
 
Thanks for your input.
17" rims are hit and miss if they will work. 18" almost always clear for reasons explained several times with possible Interference with the tie rod and when turned lock to lock with the upper control arm.
 
Can somebody fill in the blanks for me? Running disc brakes and 8-3/4 from a '73 dart Sport on my '69 Valiant. Wanting to mount rims without spacers, moving springs, or major fender mods if I can

Front
18"x8" with 245/??/R18 and 5.25" Back Space
Rear
18"x9" with ???/??/R18 and ?.?? Back Space

Considering going with these. My little grocery getter has fresh B5 blue, thinking dark bronze with a machined lip..

musclecar70_4-FL.jpg
 
Going with Mini Lites or a Camaro? Both look good really
 
Just to be clear, those of you with 18x9's on the front, say it is easier To get a 9 wide with an 18 than a 17?

Just saw a valiant at the show this Sunday with 18x9s with 285's on it! I think it was "tomswheels" old car...? Purple valiant.

Yes, it's easier to get an 18x9" on the front than a 17x9. I wouldn't plan on running a 17x9. I've only ever heard of one car that did it with a set of 17x9" Cobra R 5 spokes that had a 6" backspace, and he later admitted he had some clearance issues. Most 17" rims start to have outer tie rod end interference issues at about 5.6" of backspace. That will vary by the rim design. But with a 9" wide rim 6" of backspace is pretty much the minimum with a 73+ disk brake set up and 275's up front, any less and you're into the fenders. With 255's you might get away with a little less backspace, but not 5.6". That's with the stock tie rods, if you used a heim conversion like Hotchkis' tie rod set up you might have better luck.

Tomswheels valiant actually has 18x10's in the front with 285's. But he also use a porta-power to push his front fenders out.

Can somebody fill in the blanks for me? Running disc brakes and 8-3/4 from a '73 dart Sport on my '69 Valiant. Wanting to mount rims without spacers, moving springs, or major fender mods if I can

Front
18"x8" with 245/??/R18 and 5.25" Back Space
Rear
18"x9" with ???/??/R18 and ?.?? Back Space

Considering going with these. My little grocery getter has fresh B5 blue, thinking dark bronze with a machined lip..

245/40/18 would be the profile you're looking for in the front. That's a 25.7" tall tire.

In the back with the stock spring locations I would also run a 245/40/18. You might be able to fit a 255/40/18 but it will depend on your particular car's clearances and ride height. You could also run a 245/45/18 (26.7" tall) if you like taller tires in the back. I'm assuming you've got an A-body 8 3/4 with aftermarket BBP axles? If that's the case you'd want about 5" of backspace for a 9" rim. Some cars might need a small spacer, but it's better to have too much backspace than not enough. But, you really don't need a 9" rim. An 8" wide rim will work for the 245's, and you could run 4.75" of backspace with that. If you want to try to go with a 255 you'd need the 18x9".
 
I don't think you would get a 9" wheel on the back of a 69 Valiant without moving the springs in.
 
I don't think you would get a 9" wheel on the back of a 69 Valiant without moving the springs in.

You can. You don't need to because a 245/40/18 will fit on an 8" wide rim, but the 9" rim will fit. Remember the section width on a 245 is just barely under 10", which is what 9" wide rim will measure from outside lip to outside lip. The valiant's have a higher wheel opening in the quarter than the Dart's do, so it's a little less of an issue unless your car is slammed on the ground for ride height. On the 70+ Dart's there's about 11" from the quarter to the springs with the stock spring location. The 67-69 Darts are a little tighter, but not a ton and there are guys that have run 245's on them with the stock spring locations. You would have to measure your backspacing perfectly because you'd need your spring clearance to be at about 3/8" and your quarter clearance to be about 5/8", but if you did that successfully it shouldn't rub. With the tolerances getting that tight it might not work for everyone though, anybody that wanted to do it would absolutely have to measure their own car.

I would say it's more headache than it's worth since you'll still be stuck with a 245 and running the 8" wide rim will squeeze the 245's in a little to make life easier for clearance.
 
At some point I had a 15 x 8.5 center line wheel on the back of a 68 valiant with "around" 5 inches of back space, those needed a bit of hammering inside the wheel well....now if you are getting wheels that are wide you should be measuring the car you are going to be installing them on.
 
Hmmmmm. I didn't know that. I didn't think the offset hangers moved them that far.

They don't move them that far, only about a 1/2". But that's all it takes. The offset hanger/shackle kit makes the wheel tub the narrowest part instead of the springs.

I have the offset kit on my Duster. With my 295's I only have about 3/8" to the springs, but I've never hit them. I have, on the other hand, had the tires rub on the inside of the wheel tub before I installed my rear sway bar. If you keep the stock wheel tubs, the 1/2" offset is all you need. Even if you did do the full 3" spring relocation it wouldn't buy you any more space without a mini-tub.
 
So, since I've sort of done this already with my car. I got 18 x 9" wheels to fit in the stock '68 Dart wheel wells with a tad bit of rubbing on all 4 corners. I used a stock A-body 8 3/4 and Dr Diff's rear disc brake. Unfortunately I needed two different offset wheels, but now that I think of it, most performance tires are directional anyway so they'll look stupid if rotated. With the 18 x 9" wheels and 255/40/18 tires, I was able to get the front to clear with no problem (I cut out the inner quarter panel supports) and the rears were tricky as my rear end was offset to one side over the other. So, we're just going to roll the fenders. I have a set of MP offset shackles (0.75") that will help me put 275's under there with no problem. I might do a wheel change, but it would be with something I like a little more visually and is lighter.
 
I usually have to replace the rear tires 3 times before I have to replace the fronts. So I save money by not replacing all (4) tires every other time. So I need to have wider rear tires.

Can I ask why is everyone so afraid to mini tub and relocate the springs on their A-bodies?
 
I usually have to replace the rear tires 3 times before I have to replace the fronts. So I save money by not replacing all (4) tires every other time. So I need to have wider rear tires.

Can I ask why is everyone so afraid to mini tub and relocate the springs on their A-bodies?

First on your logic, if you were rotating the tires the rears would last longer and you'd go longer between replacements. The amount of wear doesn't change, it just gets evenly distributed. You're spending the same amount of money, you're just not doing it all at once.

As far as the mini-tub goes, I don't think people are "afraid" to do it. But it does require a pretty significant amount of welding, which not everyone can do themselves. And, it's not a small amount of work so it's not cheap to pay someone to do it. Guys that are paying to have it done (or are doing it as a business) are paying(or charging) $1k to $1,500 just in labor. See this thread cost to inboard rear springs.

Then there's the old "why do you need tires that big"? With Dart's and Valiant's you can get a 275 in there with a 1/2" offset and a little trimming on the quarter lip. Would it be nice to get a 295? Of course. But do you need a 335? Not unless you're putting down 900 hp. And remember, Duster, Demon's and Dart Sports can get a 295 in the back with the 1/2" offset and some trimming. So, I think it becomes a diminishing returns thing. 275's will support a pretty high horsepower car, and are more than wide enough to make an impression at an autoX. Yeah, if the space was there I'm sure more people would go a little bigger, but I also don't think most people want to run 335's. And a relocation and mini-tub is a lot of work if you only want to add another 3/4" of section width you probably don't need to begin with.

And of course, there are plenty of folks that don't want to do that amount of cutting on an original car.
 
I'm currently doing the spring relocation and mini tub. The reason being is it opens up more options. If you look at standard cast and 2 piece 18x12 and 19x12 rims, most are offered with offsets in the +5 to +30 range. I can also go with a wider slick in the back if I ever want to go to the strip. Yes, I am also narrowing a 8 3/4 rear which costs money too. I see rear end narrowing getting thrown around as being cheap. I can't see that coming under $1000 with new axles for the average Joe.

72bluNblu, you should write a book for all these guys. Thanks for all of your info. You're an asset on here.
 
Oh don't get me wrong doing the mini-tub and relocation definitely opens up a lot of options, especially if you set up a custom width rear axle. I just think that for most folks it's a lot of money/work for what they're getting out of it. I considered doing it with my Duster, but I decided the utility of the fold down rear seat was more useful than running really wide rear tires. Being able to run 295's pretty much sealed the deal. My 340 is putting out a little north of 400 hp, so 295's are more than enough. And since all of my cars are drivers first none of them are ever likely to get an engine with more than 450 hp, so 275's and 295's are plenty.

And thanks! :D
I just figure I did all the work and research to figure all that stuff out so I might as well share. I dunno about a book though, there really isn't that much to it. A little research and some math. :)
 
What's the front wheel and tire size of this convert? I've got a similar 67 and want to do 17's in the front and 18's in the back but really don't want to do any modifications to make them fit. Did you have any fitment problems at all?
Fronts are 17x8 4.5 back space 225/45R17 tire no fitment problems or mods done on the front or rear
 
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