18x9.5 +12

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My 18x9's are +35. I lose 5mm to my 13" brakes, so, +30 if you're comparing to a 73+ disk brake track width.

What's the 5mm's you lose to your brakes? The thickness of the rotor at the hub?

Curious if you know if your brake kit has any built in offset beyond the 73+ brake track width. I know that AndyF's kits pushed the wheels out some extra amount at some point, probably when he started using his own hub. As I recall, this was so that late model 17" Mustang wheels were easier to use and put the wheel/tire in about the same place as it would be on a stock car. I know there was cross pollination between Andy and Cass, but I don't know if Cass's hubs are based on Andy's design. If they are, there might be some additional offset built into your brakes that negates some more of the positive offset on your wheels.

Just curious if you have looked into that at all.
 
After rolling the fender as flat as I could, the tire now clears pretty good at the ride height I plan on running. But when I set the suspension on the bump stops, it starts to hit the fender as the steering is approaching full lock.
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Keep in mind, this is not the final product. It started raining before I could finish the one side I’ve been working on, but it’s to a point now where it would probably never rub. I just used some random hardware I had laying around to see if this would even work. And it does!
I attached a turnbuckle to the unrolled part of the fender and the inner fender piece. This allowed me to loosen the turnbuckle until the fender was pushed out just enough.
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Every picture was taken with the suspension resting on the LCA bump stops. Once I add another turnbuckle to the front side of the wheel well, I don’t see it ever rubbing anywhere.
I may not even need the other turnbuckle, so I’m going to wait until I drive it with this setup before I drill anymore holes.

I did the same pushing/holding the top of the lip out. But I just used washers.

you might consider a countersunk Allen bolt for attaching to lip so the tire won’t catch it.

I didn’t have access to a fender roller like that. It was about 10 years ago. So I used the baseball bat technique
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I did the same pushing/holding the top of the lip out. But I just used washers.

you might consider a countersunk Allen bolt for attaching to lip so the tire won’t catch it.

I didn’t have access to a fender roller like that. It was about 10 years ago. So I used the baseball bat technique
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I plan on getting some different bolts, this is just stuff I had laying around for testing purposes.
 
I'm still perplexed how you fit that much tire under there. I have to find someone who has a fender roller or buy one for myself. I'm scratching my head how I'm going to get 265/35/R18's under my Dart.

In the back it's because you've got a Dart. The Dusters/Demons/Dart Sports have a full 1" extra space going to the quarters. Even with the 1/2" spring offsets 275's can be really tight on the Darts.

In the front they should fit fine, I had very little issue with the 275/35/18's beyond the front lower corner of the fender. The fender roll was only because of how much I've lowered my car, and like Craig has shown the only rubbing I really ever got was going in and out of parking lots- bascially the combination of having the wheels turned and suspension compression at the same time. Since I've rolled and pushed the fenders they're well clear. I've considered going to 285/35/18's, but I'd need new rims up front since the 18x9's are too narrow for that.

After rolling the fender as flat as I could, the tire now clears pretty good at the ride height I plan on running. But when I set the suspension on the bump stops, it starts to hit the fender as the steering is approaching full lock.
View attachment 1715684871
View attachment 1715684872
View attachment 1715684875
Keep in mind, this is not the final product. It started raining before I could finish the one side I’ve been working on, but it’s to a point now where it would probably never rub. I just used some random hardware I had laying around to see if this would even work. And it does!
I attached a turnbuckle to the unrolled part of the fender and the inner fender piece. This allowed me to loosen the turnbuckle until the fender was pushed out just enough.
View attachment 1715684874
View attachment 1715684876 View attachment 1715684877
Every picture was taken with the suspension resting on the LCA bump stops. Once I add another turnbuckle to the front side of the wheel well, I don’t see it ever rubbing anywhere.
I may not even need the other turnbuckle, so I’m going to wait until I drive it with this setup before I drill anymore holes.

Looking good!!! :thumbsup:

Great work on the fenders, they look awesome. Great idea with that turnbuckle as well. Not sure I'd leave that on my car, but since the suspension is on the stops and there's clearance I suppose there's no reason not to. You could do it up nicer with a pair of 1/4" heims and a threaded tube, although that would be more expensive of course.

What's the 5mm's you lose to your brakes? The thickness of the rotor at the hub?

Curious if you know if your brake kit has any built in offset beyond the 73+ brake track width. I know that AndyF's kits pushed the wheels out some extra amount at some point, probably when he started using his own hub. As I recall, this was so that late model 17" Mustang wheels were easier to use and put the wheel/tire in about the same place as it would be on a stock car. I know there was cross pollination between Andy and Cass, but I don't know if Cass's hubs are based on Andy's design. If they are, there might be some additional offset built into your brakes that negates some more of the positive offset on your wheels.

Just curious if you have looked into that at all.

It's the brake kit, yes. The DoctorDiff 13" cobra style rotor kit adds about 5/16" to the track width, or basically 5mm. I'm not sure if its the hubs or the rotors or where it comes in. Andy's original Viper kit added like an extra 1/2" to the track, but that was before the aluminum hubs that are used now.

I've spoken with Cass about it, the current 13" kits only add 5/16" compared to the track width of the stock 73+ disks (although that track is wider than the SBP cars). I try to always give my offsets relative to the 73+ factory disks.
 
....snip.... It's the brake kit, yes. The DoctorDiff 13" cobra style rotor kit adds about 5/16" to the track width, or basically 5mm. I'm not sure if its the hubs or the rotors or where it comes in. Andy's original Viper kit added like an extra 1/2" to the track, but that was before the aluminum hubs that are used now.

I've spoken with Cass about it, the current 13" kits only add 5/16" compared to the track width of the stock 73+ disks (although that track is wider than the SBP cars). I try to always give my offsets relative to the 73+ factory disks.

Dang. I hate gaining any track width because it forces you run more backspace on the rim.

And that makes you loose that aggressive deep look to the rim.
 
Dang. I hate gaining any track width because it forces you run more backspace on the rim.

And that makes you loose that aggressive deep look to the rim.

It really isn’t much. I run an 18x9 +35 on the front, it basically positions the wheel the same as a +30.

And if you’re willing to do some fender work Craig has shown you can go all the way to +12, which he’s made look a lot easier than I ever thought it would be. There’s a lot of rims in the 18x9.5” size with offsets in the +20 to +25 range. I know because I’ve looked at them but discounted them because of the offset. With your Barracuda and the work you’ve already done on your fenders I don’t they they’d be that much work with the right tires.
 
It really isn’t much. I run an 18x9 +35 on the front, it basically positions the wheel the same as a +30.

And if you’re willing to do some fender work Craig has shown you can go all the way to +12, which he’s made look a lot easier than I ever thought it would be. There’s a lot of rims in the 18x9.5” size with offsets in the +20 to +25 range. I know because I’ve looked at them but discounted them because of the offset. With your Barracuda and the work you’ve already done on your fenders I don’t they they’d be that much work with the right tires.

I just think when you go to these larger diameter rims, you visually loose that deep look even keeping the width and offset constant.

I like the deep look of my minilites. They are 15x9 with 4 1/8” backspace and 4 7/8” on the front side.

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Brad’s 18x11 rear rims have 5.5” backside and front side. but I think they look more shallow than mine. Even though they technically are not.


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I just think when you go to these larger diameter rims, you visually loose that deep look even keeping the width and offset constant.

I like the deep look of my minilites. They are 15x9 with 4 1/8” backspace and 4 7/8” on the front side.


Brad’s 18x11 rear rims have 5.5” backside and front side. but I think they look more shallow than mine. Even though they technically are not.


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My setup and 72bluNblu's is exactly the same wheel width, offset, brakes, and tire size. A lot of that has to do with the rims you choose. The torque thrust M's are made differently than the enkei's, being that the spokes are made to curve around the brakes...best picture I have:

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The harsh reality of the smaller rim diameters is the tire choice blows and a rim under 18" you have to worry about tierod clearance to the rim and tire, which in most cases forces a smaller tire width.

Honestly I would have gone with a 17" rim if the tie rod wasn't an issue, just because of the road conditions in my area. My other two brand x cars run 17's with the same OD.
 
My setup and 72bluNblu's is exactly the same wheel width, offset, brakes, and tire size. A lot of that has to do with the rims you choose. The torque thrust M's are made differently than the enkei's, being that the spokes are made to curve around the brakes...best picture I have:

View attachment 1715687336

The harsh reality of the smaller rim diameters is the tire choice blows and a rim under 18" you have to worry about tierod clearance to the rim and tire, which in most cases forces a smaller tire width.

Honestly I would have gone with a 17" rim if the tie rod wasn't an issue, just because of the road conditions in my area. My other two brand x cars run 17's with the same OD.

agree completely. I’d like the lighter weight and smaller diameter 17” rim too.

But that ship has sailed

I’m aiming to cram a 295 to 305. But I don’t think there’s much tire choice and the availability will fade in the future. Thoughts?
 
It's the brake kit, yes. The DoctorDiff 13" cobra style rotor kit adds about 5/16" to the track width, or basically 5mm. I'm not sure if its the hubs or the rotors or where it comes in. Andy's original Viper kit added like an extra 1/2" to the track, but that was before the aluminum hubs that are used now.

I've spoken with Cass about it, the current 13" kits only add 5/16" compared to the track width of the stock 73+ disks (although that track is wider than the SBP cars). I try to always give my offsets relative to the 73+ factory disks.

Gotcha. Sounds like the hubs that Cass sells aren't a direct swap for the one's Andy used then. Good to know.

...and a rim under 18" you have to worry about tierod clearance to the rim and tire, which in most cases forces a smaller tire width.

Honestly I would have gone with a 17" rim if the tie rod wasn't an issue...

I wonder if that was the other (only?) reason Andy pushed the face of the hub out some? So the tie-rod would clear.

So far I am ok with my 17x8's and +24mm offset, but not by much. If I want to go to a 275 (someday) on the front, probably going to have to step up to an 18" wheel.
 
Gotcha. Sounds like the hubs that Cass sells aren't a direct swap for the one's Andy used then. Good to know.



I wonder if that was the other (only?) reason Andy pushed the face of the hub out some? So the tie-rod would clear.

So far I am ok with my 17x8's and +24mm offset, but not by much. If I want to go to a 275 (someday) on the front, probably going to have to step up to an 18" wheel.

I had the same wheels and tires on with an 11.75" setup but I had to use a 5 or 10mm spacer (I can't remember honestly) so the wheels wouldn't hit the hotchkis control arms at full droop with the wheels turned. With the Dr Diff 13", everything clears, but let's be honest it's still not a lot of space.

Fresh picture from the garage today. Closest point is about a 1/2" clearance or so. Not a chance on a 17" wheel.
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I had the same wheels and tires on with an 11.75" setup but I had to use a 5 or 10mm spacer (I can't remember honestly) so the wheels wouldn't hit the hotchkis control arms at full droop with the wheels turned. With the Dr Diff 13", everything clears, but let's be honest it's still not a lot of space.

Fresh picture from the garage today. Closest point is about a 1/2" clearance or so. Not a chance on a 17" wheel.
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yeah, those Hotchkis A-body UCA’s take a wide turn from the UBJ’s..... I could not run rear mounted pin calipers with 11.75 disks. I had to swap spindles side to side and mount calipers in the front. -not sure about slider calipers.

That worries me about 13” disk upgrades too.

I want them rear mounted so I can run brake ducts.
 
yeah, those Hotchkis A-body UCA’s take a wide turn from the UBJ’s..... I could not run rear mounted pin calipers with 11.75 disks. I had to swap spindles side to side and mount calipers in the front. -not sure about slider calipers.

That worries me about 13” disk upgrades too.

I want them rear mounted so I can run brake ducts.

I had the same issue when I put the hotchkis control arms on. I think the Dr Diff kit is front mount only with the hotchkis UCAs.
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I had the same wheels and tires on with an 11.75" setup but I had to use a 5 or 10mm spacer (I can't remember honestly) so the wheels wouldn't hit the hotchkis control arms at full droop with the wheels turned. With the Dr Diff 13", everything clears, but let's be honest it's still not a lot of space.

Fresh picture from the garage today. Closest point is about a 1/2" clearance or so. Not a chance on a 17" wheel.
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I just realized that my homebuilt brake setup includes a slip on rotor over a cut down OEM rotor for a hub. So, I guess I have a .25" or so spacer on the front as well.
 
I just think when you go to these larger diameter rims, you visually loose that deep look even keeping the width and offset constant.

I like the deep look of my minilites. They are 15x9 with 4 1/8” backspace and 4 7/8” on the front side.

View attachment 1715687334

Brad’s 18x11 rear rims have 5.5” backside and front side. but I think they look more shallow than mine. Even though they technically are not.


View attachment 1715687335

Love those mini-lites on Brad's car, that thing is sweet! I followed his build for a long time on the Cuda-Challenger board. But the front tire clearances on the Challenger's are quite a bit different than on the A bodies. On my Challenger I was running 17x9's with a 0 offset, 5" of backspace. They had plenty of room. Despite Craig showing that the +35 isn't absolutely necessary on an A if you want to do fender work you're still not gonna get away with a 0 offset like the E's can use, and that definitely changes the front space you'll have.

agree completely. I’d like the lighter weight and smaller diameter 17” rim too.

But that ship has sailed

I’m aiming to cram a 295 to 305. But I don’t think there’s much tire choice and the availability will fade in the future. Thoughts?

In 17's there's pretty much nothing street legal past a 275/40/17 anymore. There's a few track only tires in 295/35/17 and 315/35/17, but that's it. And they're all sub 100 treadwear, so they're not even legal for a lot of the autoX or optima street car classes.

Heck even in 18's the selection gets pretty limited once you get past 275's. There are a few street legal 295 choices still, but not much again until you get to a 335. I was looking at possibly doing an 18/19 stagger in the future because of that, with my reverse mini-tub and quarter rolling I may be able to do 315's or 325's in the back now. But there's pretty much nothing in that width that's the right height for these cars on an 18" wheel.

Seems like those UCAs are going to have to go when I do this.

You can go to the SPC's Peter sells, I run my 13" cobra calipers to the rear on my Duster. At least the 1st gen ones, looks like the new 2nd gen SPC's may be wider down at the ball joint. Although I may get those for my Challenger and get rid of the Hotchkis UCA's on it.

I think the SPC's are a win anyway compared to the Hotchkis UCA's. They're a heck of a lot easier to adjust, and the Delrin bushings will outlast the heims by years and years.
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In the back it's because you've got a Dart. The Dusters/Demons/Dart Sports have a full 1" extra space going to the quarters. Even with the 1/2" spring offsets 275's can be really tight on the Darts.

In the front they should fit fine, I had very little issue with the 275/35/18's beyond the front lower corner of the fender. The fender roll was only because of how much I've lowered my car, and like Craig has shown the only rubbing I really ever got was going in and out of parking lots- bascially the combination of having the wheels turned and suspension compression at the same time. Since I've rolled and pushed the fenders they're well clear. I've considered going to 285/35/18's, but I'd need new rims up front since the 18x9's are too narrow for that.

It's pretty obvious that in the rear I wouldn't be able to fit more than a 275. The front on a +12 wheel surprised me. I didn't figure that a fender roller would stretch the fender out that much. Although, my car is pretty low as is.

I'm thinking about upgrading at least tires in the near future, if not wheels too, but to play it safe I may end up going with a 265/35/18 as I want to reduce the likelihood of rubbing altogether.
 
It's pretty obvious that in the rear I wouldn't be able to fit more than a 275. The front on a +12 wheel surprised me. I didn't figure that a fender roller would stretch the fender out that much. Although, my car is pretty low as is.

I'm thinking about upgrading at least tires in the near future, if not wheels too, but to play it safe I may end up going with a 265/35/18 as I want to reduce the likelihood of rubbing altogether.

That’s definitely a good plan. I know I always get caught up in running as much as I think I can fit the first time. But tires don’t last forever, running a little bit smaller than what you think is possible and going bigger next time around is a safer plan for sure. And with tires nowadays even if you don’t wear them out you’re buying a new set in like 6 years anyway.

Believe me, I’m not sure if anyone could be more surprised than me about those 18x9.5” +12’s. And I’ve rolled my front fenders already. I may not have pushed them as much because I was trying not to pop my paint, but still!
 
That’s definitely a good plan. I know I always get caught up in running as much as I think I can fit the first time. But tires don’t last forever, running a little bit smaller than what you think is possible and going bigger next time around is a safer plan for sure. And with tires nowadays even if you don’t wear them out you’re buying a new set in like 6 years anyway.

Believe me, I’m not sure if anyone could be more surprised than me about those 18x9.5” +12’s. And I’ve rolled my front fenders already. I may not have pushed them as much because I was trying not to pop my paint, but still!

My only problem with a 265/35/18 is that it's about 3/4" shorter in diameter and my car is already low. If you look at the new tires coming out, they all seem to be coming out wider for the same size. For instance, compare the section width of a 275/35/18 for both a Falken 615K+ (10.8") and an RT660 (11.2"). The RT660 is 0.4" wider on the same width wheel. A 265/35/18 RT660 is still 10.9" wide. It is making tire selection a little more difficult for me because I'm forced to go down to a much smaller diameter tire on my already low car. Depending on how things go, I may need to get a wider wheel (9" current) and maybe stick with a 255/40/18 which is the same price or more expensive and has less availability than it's wider counterparts.
 
Here they are all mounted at the ride height I’ll be driving at.
I’d go lower if I could get in my driveway without dragging the exhaust.
1” spacer on the back to even out the front and rear track widths
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After daily driving the car for a while now, this wheel/tire size has been great. The fronts do not touch anything under any circumstances, but the rears barely scrub the rear fender arch when I drive into a steep driveway diagonally. I could easily fix this with a slightly smaller spacer, or a a few taps of a hammer, but it’s such a slight scrub, I’m not going to worry about it.
Also discovered that the car now handles better than my seats hold me in place. Haha
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