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Guys w 18s...HELP...

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Old Apr 12, 2015 | 02:46 PM
  #1  
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Default Guys w 18s...HELP...

Hi all!,

OK!

I am looking to put 18s on my 69 vert which has 500hp 454...but wanted to know thoughts on
  1. is there a performance difference between 8 inch wide vs 9.5 inch wide rears? (thinking YES, obviously)
  2. Do you run a REAR sway bar with 18s?
    is it ok without...based on no space...
  3. Did you move parking brake?
  4. after reading, I see most go 5" backspacing for 18x9.5...recommendations?

THANKS!!!
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Old Apr 12, 2015 | 04:20 PM
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Well using a 8" with the correct offset is the same as stock.
Factory sway bar is fine and no issues with the parking brake.

As for wider it needs to be matched with the correct tire width. 275 should be perfect.

It all depends on the offset to clear the parts on the inside. Then not too much to stick out beyond the fender.

There are some great websites with offset calculators that let you also input suspension and and body parts.

With the wheel you have there now measure inward to the closest contact point. That should be the brake bracket. Then measure to the fender.

Take those wheel offsets and plug them in. Then you can play with extra data by say relocating the bracket.
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Old Apr 12, 2015 | 08:03 PM
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hmmm...great info!

were you able to keep the sway bar? how wide are yours?

R
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Old Apr 12, 2015 | 09:07 PM
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Originally Posted by Factor
hmmm...great info!

were you able to keep the sway bar? how wide are yours?

R
285/40/18 on 9.5 with 5" back spacing on the rear no swaybar
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Old Apr 13, 2015 | 11:16 AM
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THANKS!

any issues with no sway bar? (cornering?)

R
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Old Apr 13, 2015 | 12:07 PM
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I think if you used a factory swap bay with the correct endlinks you would be fine.
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Old Apr 13, 2015 | 02:12 PM
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18x9 C5 Zo6 knock offs on my 79 with spacers I didnt have to move the ebrake cable, stock style trailing arms rear sway bar wasn't connected before the swap and have heard from guys that auto cross/road race these cars a rear sway bar isn't needed.
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Old Apr 13, 2015 | 02:37 PM
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I run an 18x9" 4.75" backspacing with a 275-40-18 tire. Parking brake bracket is in stock location and I run a rear sway bar. It's tight.

Last edited by Neil B; Apr 13, 2015 at 02:43 PM.
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Old Apr 13, 2015 | 04:30 PM
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Originally Posted by mvette76
285/40/18 on 9.5 with 5" back spacing on the rear no swaybar
I'm almost identical except my b-s is 5.5". Each rear inner tire kiss the side of the inside wheelhouse on hard bumps otherwise, I'm a happy camper. I slalom around potholes as needed to avoid contact.
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Old Apr 13, 2015 | 05:48 PM
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Originally Posted by Dustup7T2
I'm almost identical except my b-s is 5.5". Each rear inner tire kiss the side of the inside wheelhouse on hard bumps otherwise, I'm a happy camper. I slalom around potholes as needed to avoid contact.
285/40/18 On 9" rim with 5" backspace - no sway bar - light 'polishing' of inner fenderwells. With low profiles and wide rubber many will debate whether the sway bar is actually needed!
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Old Apr 13, 2015 | 11:08 PM
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great info!

any issues cornering with no sway bar guys?

i am assuming stock parking brake locations...

thanks,
Ron
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Old Apr 14, 2015 | 10:54 AM
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ALSO...anyone stick out past the quarter??

Thanks,
Ron

I totally want wider, but dont want to sacrifice too much. obviously 18x8 is easy and can keep all stock stuff without any worry...

talked to VBP...they recommended offset trailing arms and rear dual sway bar...kind of pricey...thus wondering if the wider rims are worth the price?....

love the thoughts!!!

thanks,
Ron
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Old Apr 14, 2015 | 11:43 AM
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I have 285 on 18x10 with 5.75 backspacing. Had to add a 1/4" spacer as I wasn't comfortable with the space left between the tire and frame. With the spacers, there is no rubbing at all even on hard cornering. I do run with offset trailing arms which have parking brake bracket moved and also an offset swaybar. If I was to order new wheels, I would go with 18x9.5 with 5.5 backspace, it really seems the best fit with the hardware I'm running.

Before this mod, I didn't have a swaybar in the back but I can't tell you if the swaybar alone makes a difference as I changed quite a few things at the same time. But IMO, a soft spring with a large sway bar will always outcorner a stiffer spring with no sway bar and make the ride more comfortable anyway. Right now, I have a composite 360 spring and thinking about going down a notch.
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Old Apr 14, 2015 | 02:10 PM
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TT2 18x9 with 275/40-18 5" BS, had to remove my aftermarket sway bar due to some rubbing. No big deal since I only race straight forward ;-)

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Old Apr 15, 2015 | 09:14 AM
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lohkay- great info! thanks! what kind of "offset sway bar"? is it the rear dual mount from vbp?

Peter...SEXY CAR! thanks!
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Old Apr 15, 2015 | 10:19 PM
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I have 18 x 9.5 rears with 5" BS with 275 tires. No sway bar. I relocated e brake but may not have had to. Handles fine with out sway bar. Fronts are 18 x 8 with 4" BS with 255 wide tires.
No rubbing anywhere.


Last edited by tixeon; Apr 15, 2015 at 10:40 PM.
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Old Apr 15, 2015 | 11:22 PM
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Old Apr 17, 2015 | 08:02 PM
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Originally Posted by Factor
lohkay- great info! thanks! what kind of "offset sway bar"? is it the rear dual mount from vbp?

Peter...SEXY CAR! thanks!
I bought it from vansteel with their offset trailing arms. It wouldn't surprise me if its the same as the VBP. Essentially, it has an offset bracket that goes in the original location on the trailing arms and you need to add mounts that bolt through holes you drill in the cross frame.

Let me know if you want more info.
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Old Apr 18, 2015 | 11:27 AM
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AWESOME!!!

Thanks guys!

Peter...looking at your car again...LOVE IT! Great stance too! What susp do you have in the back to get that low?
and front?
Front tire size & rim too?

thanks,
Ron
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