Author Topic: Anybody running 15x8" wheels on the front?  (Read 4290 times)

Offline Road_Runner

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Anybody running 15x8" wheels on the front?
« on: October 17, 2011 - 11:41:04 PM »
I'm seriously considering putting the 1" rear offset hangers and a 70 B Body rear in the Barracuda and going to 15x10" rallyes on back.  I'll have both 15x7" wheels which are on the front now, and the 15x8"s which are currently on the back so I'm trying to decide which wheels go best with the new 10" rears.  If you run 15x8s on front what tires do you run?  Do you have to use a custom offset or spacers?  I like the way the 7" look with 245/60's on the front now, just trying to decide if the 8" would look/handle better when I go to 10" on the back. 

Thanks in advance, Jim
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black




Offline HP2

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Re: Anybody running 15x8" wheels on the front?
« Reply #1 on: October 18, 2011 - 09:54:44 AM »
I've run a couple different combos of 15x8s. The best fitting were with 235/60 tires and 4.75" backspace. This pulled the tire in tight enough to minimize any potential interference with the fender yet kept it from contacting the ball joint and control arm. The tightest fit was a 15x8 with 4.5" backspace and a 255/55 tire. This set up required a rolled lip on the upper half of the wheel opening and removal of the fender stabilizing brace at the top of the wheel opening.  I've never tried a 245 tire.

Offline Road_Runner

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Re: Anybody running 15x8" wheels on the front?
« Reply #2 on: October 19, 2011 - 10:56:52 PM »
I've run a couple different combos of 15x8s. The best fitting were with 235/60 tires and 4.75" backspace. This pulled the tire in tight enough to minimize any potential interference with the fender yet kept it from contacting the ball joint and control arm. The tightest fit was a 15x8 with 4.5" backspace and a 255/55 tire. This set up required a rolled lip on the upper half of the wheel opening and removal of the fender stabilizing brace at the top of the wheel opening.  I've never tried a 245 tire.

I'd rather stay away from modifying the fender etc. for the tires to clear, so maybe I'll leave wll enough alone and just stay with my 245/60's on the 7" rims. 

Thanks, Jim
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black

Offline brads70

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Re: Anybody running 15x8" wheels on the front?
« Reply #3 on: October 20, 2011 - 08:45:43 AM »
I'm planning the B-Body rear end this winter too and am looking at 10" rims for the back. I'd like to put the 8" rims from the back to the front too. Things get tight up front though? I'll have to do some meausuring .....
From what I've read on here it seems each car is different them you push things to the max, production tolerances I guess?
Brad
1970 Challenger 451stroker/4L60 auto OD
Barrie,Ontario,Canada
Proud to own one of the best cars ever made!!!!!

My restoration thread 
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Offline 72bluNblu

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Re: Anybody running 15x8" wheels on the front?
« Reply #4 on: October 20, 2011 - 12:07:20 PM »
With a 15x8" in the front you'll have to be careful with the backspacing. You'll need at least 4.5" to get it off the fender, but 5" is probably the max before you get into the tie rod, ball joint and UCA.

I run a 17x9" rim in the front, but since I have a 2" drop spindle my tie rod is basically in the same position it would be in relation to a 15" rim. I have 5" of BS, and only about 3/8" to between the tie rod and the lip of the rim. I run a 275/40/17, but its also only a 26" tall tire.

And as Brad pointed out, as you get close to the max your production tolerances really come into play. I had no issues at all with my driver's side, but on the passenger side I had to play with the ride height and roll the fender lip a little to get it to clear.

Offline HP2

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Re: Anybody running 15x8" wheels on the front?
« Reply #5 on: October 20, 2011 - 03:06:33 PM »
Nah, 5" of backspace won't work with a 15" wheel. Depending on the rim steps, it hits either the ball joint or control arm. That is why mine ended up with 4.75" backspace. It was built as a 5" bs rim and I had to add the .25" spacer to get it off the arm.

Offline 72bluNblu

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Re: Anybody running 15x8" wheels on the front?
« Reply #6 on: October 20, 2011 - 05:25:16 PM »
Nah, 5" of backspace won't work with a 15" wheel. Depending on the rim steps, it hits either the ball joint or control arm. That is why mine ended up with 4.75" backspace. It was built as a 5" bs rim and I had to add the .25" spacer to get it off the arm.

Interesting! I guess the geometry is still a little different with the drop spindle and 17" rim. I know mine is about as close as you can make it, and I do kinda wonder if I actually have 5" of backspace on those rims, or if the Summit brand runs a little short on that particular measurement. The rims seem further out than I thought they would be.

Which is another point entirely, each wheel manufacturer will be a little different on their measurements, and the design of the lip of the rim. When you start getting really close, all of those little differences start to matter.

Offline brads70

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Re: Anybody running 15x8" wheels on the front?
« Reply #7 on: October 20, 2011 - 05:26:15 PM »
Here is what I have to choose from? Mine are the bottom rim ( superlites)
http://www.performancewheels.com.au/Home/Wheels.asp?theGroup=C&Cat=Classic

to get into inches from MM divide by 25.4 ( for the backspacing)
I have 7" front and 8" on the rears now.
Brad
1970 Challenger 451stroker/4L60 auto OD
Barrie,Ontario,Canada
Proud to own one of the best cars ever made!!!!!

My restoration thread 
http://www.cuda-challenger.com/cc/index.php?topic=59072.0
 My handling upgrade post
http://www.cuda-challenger.com/cc/index.php?topic=73985.0

Offline Cuda54

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Re: Anybody running 15x8" wheels on the front?
« Reply #8 on: October 20, 2011 - 05:48:40 PM »
I am running 15"x8"with 5"BS all the way around on my 72 Cuda and they do not hit anything. 245x60x 15" up front and 275x60x15" rears they are Cragar SS.

Offline Road_Runner

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Re: Anybody running 15x8" wheels on the front?
« Reply #9 on: October 21, 2011 - 10:37:42 AM »
I am running 15"x8"with 5"BS all the way around on my 72 Cuda and they do not hit anything. 245x60x 15" up front and 275x60x15" rears they are Cragar SS.

That's the same size tire I'm running now on a 15x7" front rim, I'll have to go take a look to see if the extra rim width would really buy me anything running the same size tire.  My hope was to fit something a little bigger to match the bigger tires I would run on the back when I switch to 10" rims, maybe something in a 50 or 55 series if I can find that size. 

Later, Jim
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black