What tire size will work with a 15x8 front wheel?
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69_340_GTS
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I doubt you'll find any tire that will work. The wheel has nowhere near enough back spacing.
autoxcuda
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Needs to be 4 1/2" backspace to fit 245/50/15 or 225/50/15 tires. And I don't think anyone makes a 245/50/15 anymore.
Other than that you'd have to try a 60 series tire that would be too narrow for 8" wide rim. Like maybe a 205.
I've fit 245/50/15 with 15x8 4 1/2" backspace on my 68 Dart. And it was close. Also ran 225/60/15 with 15x7 4.25" backspace with poly strut bushings and 3 defy positive caster that pushed the wheel back a little.
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This. There is literally no tire that will fit on a 15x8 with 3.75" of backspace that will clear the fender, because the rim will stick out past the fenders.
For example- I run 18x9" rims with 275/35/18's up front on my Duster. You can't go wider than that without body mods, I've got about zero extra clearance to my fenders. Now, lets do some math. An 18x9" rim is 10" wide outside to outside. I have an effective backspace of 6.1" for those rims compared to a 73+ BBP disk set up. That means I have 3.9" of front space, or 3.9" of rim sticking out from the wheel mounting surface up front on my car. 275/35/18's are 10.9" wide at the section, we'll forget for a second that measurement is taken on a 9.5" wide rim. So, that means the outer plane of my tire is 4.35" outboard from my wheel mounting surface using 73+ BBP disks. On a 15x8 with 3.75" of backspace, there's 5.25" of front space. That means the rim, by itself, would stick out .9" further than the outside of the tire with the 275/35/18's I run. And really it's probably a full 1", because I don't have that section width using a 9" wide rim, they'll be squeezed in a bit.
Barracuda's have wider fenders up front than Dart's do. You'd never clear 245's on 15" rims on a Dart without serious body modification. 245/50/15's on a 15x8" rim with 4.5" of backspace would stick out a full 1/2" further than the 275/35/18's on my Duster (with a demon front end). I don't have an extra 1/8", let alone an extra 1/2".
Plus, your fenders have been modified right? Rolled and pushed out?
autoxcuda
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I have a 68 Dart GT conv also. I just don't talk about it much. I've run 225/60/15 on cop rims.
I did run 245/50/15 on 15x8 4.5" backspace rally's briefly. The 245's were really too close. Yes they would rub a little on the top fender brace bolt. But like I said, the thick poly bushing and positive caster helped with front tire clearance. Those are still very short tires. The short tire allowed me to flirt with disaster.
I now have 245/60/15 with 15x 6.5" rally's. BUT I had to push out the front corner of the wheel lips by repositioning the lower fender brace forward of the factory hole on the bottom of the fender. Pushed it out and 1-2".
Well that sounds pretty conclusive. I originally wanted a 15x7, but the wheels I chose(Cragar 69 delux) are discontinued, and limited to whatever is left in stock. The 7's weren't available.
How about tire size for a 15x6 with 3-1/2" bs? That's the next best option I believe.
How about tire size for a 15x6 with 3-1/2" bs? That's the next best option I believe.
I keep forgetting how short a 245/50/15 is! Yes that makes sense, it's only 24.6" tall, no tucking the wheel into the fender on those.
205/65/15. Could do a 215/65/15 as well, although that's a 26" tall tire so you'd want rears at least that tall as well. Plans for the rear wheels?
autoxcuda
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225/60/15. But watch the front bottom of the fender lip to tire when turning. Have someone turn the wheel and watch until it's at its closest.
Take the bottom front fender support and adjust it outward as possible. If more room is needed add a hole on the bottom fender flange forward of the original hole.
That should fit, a 15x7 with 4.5" of backspace is actually a +12 offset, so that's good, even better than the factory 15x7's. A 225/60/15 should fit as autoxcuda pointed out, and you should definitely check the front lower corner of the wheel opening for clearance. I ran 225/60/15's on 15x7's with 4.25" of backspace on my Duster and had to max out that lower fender to bumper brace, but that was all I did. The additional backspace should give you a little more room on that corner too.
You might be able to run 235/60/15's with that backspace as well, but since those would be 26.1" tall you would probably have to modify the front lower corner of the wheel opening to get those to clear. The outboard clearance to the fender would be fine, but because of the tire height the corners could be a problem. And your ride height and even your alignment would play a part in that as well. The 225/60/15 would be a much safer bet if you didn't want to worry about making any modifications to the corners.
DakotaDuster
"I'm all in."
I have these on my fronts, and although they are too wide for my wheels they'd be perfect for a 6" wide wheel, while keeping the front end down swith a sorta raked look if that's what you're after.
holy crap that's a bitty little tire! 22.76" tall? That's way shorter than the factory ever ran on these cars. Heck those tires have a shorter sidewall than most of the guys with 17" rims. I have more sidewall on the rear tires of my Duster and I have 18" rims.
Any size you want if you want your car to look like this.
DakotaDuster
"I'm all in."
It is small for sure. Here it is on my 15x4s... as you can see it's too wide of tread width for my wheels by the sidewall bulging. I goofed up on ordering after about 4 hours of finding/ordering parts. Was too close to Mopars in the Park to send back. Had mounted to get me by just for the show. Love the tread pattern... wish they offered a proper size for a 15x4.
Sorry to the OP for high jacking but got a quick question.
72bluNblu I got a 68 Valiant that I'm swap front disk onto. I got a set of 2 inch drop spindles I've had for a couple of years and 11 3/4 rotors.
Looking to get rally look a likes from summit to match the back (245 60r15 small bolt pattern) for now until i swap axles at a later date. Looking to put 225 60r 15 and have the fender cover about half the sidewall.
There's two rim options 15 x 7 with 4.25 bs or 15 x 8 4.5 bs which would be better and or fit ??? Thanks
72bluNblu I got a 68 Valiant that I'm swap front disk onto. I got a set of 2 inch drop spindles I've had for a couple of years and 11 3/4 rotors.
Looking to get rally look a likes from summit to match the back (245 60r15 small bolt pattern) for now until i swap axles at a later date. Looking to put 225 60r 15 and have the fender cover about half the sidewall.
There's two rim options 15 x 7 with 4.25 bs or 15 x 8 4.5 bs which would be better and or fit ??? Thanks
67autocross
A new iron curtain drawn across the 49th parallel
Like this... these are 225 60 15s on 15 x 7 with 4.25 backspace. I would say you are better off with 4.5 backspace... and you will likely still have to tweak things to keep them from rubbing. This car has 1.14 torsion bars and shocks with a good bit of compression dampening and I can still get some rubbing at times.
I got 1.09 bars
But seems to me yours is pretty close to the fender and 8" rims would move it out 3/4 of an inch further that way since its only got a 1/4 inch more back space.
Exactly.
15x7's with a 4.25" backspace will be a better fit. The 15x8's with 4.5" of backspace will be closer to the fenders, just like your math suggests. The 8" rim is an inch wider, but only has an extra 1/4" of backspace. So you lose a 3/4" of fender clearance. And you can only run 225's anyway, so you don't need the 8" wide rim.
I might add you don't need drop spindles with 1.09" torsion bars either. You can lower that car as much as is practical with just those bars and a smaller lower bump stop, and you'll have better suspension geometry than with drop spindles.
Thanks for the info
Ya we talked a few years ago about the drop spindles but that was after I bought them.
So gonna try them out,
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