Maximum BS
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From: Bertram (outside Austin), TX
Car: 87 GTA
Engine: L98
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Maximum BS
Anybody know the maximum BS we can run on our cars, without using spacers, a 4th gen rear end, or any trailing arm,body/suspension mods? A straight bolt-on. I've got my eyes on a set 16" x 10" with 7" of BS...
Last edited by Stephen; Feb 5, 2007 at 09:03 AM.
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Max is about 4½" on the front and 5" on the rear.
NO WAY 7" will work with no spacers etc. That's not even remotely realistic, just pure fantasy land. The tires will hit EVERYTHING. Sway bar & steering knuckle on the front; inner fender well, bump stop, & spring pocket on the rear.
NO WAY 7" will work with no spacers etc. That's not even remotely realistic, just pure fantasy land. The tires will hit EVERYTHING. Sway bar & steering knuckle on the front; inner fender well, bump stop, & spring pocket on the rear.
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From: Bertram (outside Austin), TX
Car: 87 GTA
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Well, I wasn't planning on using them on the front anyways, only the rear 2.
So...2" spacers on the rear, or a 4th gen rear with .75" spacers, and they'll fit?
It's just a killer deal for the set.
So...2" spacers on the rear, or a 4th gen rear with .75" spacers, and they'll fit?
It's just a killer deal for the set.
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Measure the clearance from the inner sidewall to EVRYTHING in there, as it is right now. Then take your wheel off and measure the depth from the hub to the sidewall. Then measure how far it is from the The sum of those 2 numbers, minus however far it is from the sidewall to the tire bead of the wheel (probably less than an inch), is the biggest BS you can POSSIBLY use. It'd be wise to keep it about ½" less than that, so you'll have that much clearance.
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From: Bertram (outside Austin), TX
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Yeah...I guess I was just avoiding doing all that. I think I'm gonna get those wheels, and see if I can find a street tire over 295, but still fits. Like a 305. I've run 295s on stock 3rd gens wheels before, so I know they'll fit. Barely, but they give a nice depth to the sidewall.
Last edited by Stephen; Feb 6, 2007 at 12:42 AM.
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From: Bertram (outside Austin), TX
Car: 87 GTA
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Transmission: 700R4
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On Skulte.com....
"rims with a maximum of 5" front and 5.85" rear backspacing"
So...7" BS - 5.85" BS = 2.15" adapter/spacer needed, so a 2" would be great...Or a 2.25".
With a 4th gen rear, it being 1.25" wider per side, that makes for a .75" adapter/spacer needed.
Are the 4th gen rear discs bigger than 3rd gens? 12.75" rotors? I already planned on swapping my 89 (11.75" rotors) rear on to my 87 (10.75" rotors) for the bigger discs.
With a 4th gen rear, I could go 2" bigger rotors, and smaller adapters/spacers, at the same time!
"rims with a maximum of 5" front and 5.85" rear backspacing"
So...7" BS - 5.85" BS = 2.15" adapter/spacer needed, so a 2" would be great...Or a 2.25".
With a 4th gen rear, it being 1.25" wider per side, that makes for a .75" adapter/spacer needed.
Are the 4th gen rear discs bigger than 3rd gens? 12.75" rotors? I already planned on swapping my 89 (11.75" rotors) rear on to my 87 (10.75" rotors) for the bigger discs.
With a 4th gen rear, I could go 2" bigger rotors, and smaller adapters/spacers, at the same time!
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Most people run 5.5 bs with a 16x10 with no problems, no way 7 will work but you only need a 1.5" spacer for them to work. Any less than 5.5bs and your tires will stick out past your fenders
here's a link for you to read
https://www.thirdgen.org/forums/susp...t=10+inch+rims
here's a link for you to read
https://www.thirdgen.org/forums/susp...t=10+inch+rims
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From: West of Toronto
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I believe Kandied91 was running a 6 3/4" bs on the rear with 285's. You can run a 6" bs with no rub on a stock rear end with stock brakes. YOu might want to add .5' just to be safe so go with a 5 1/2" bs to avoid any unforseen issues.
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6.75 backspace is with an 18 inch rim and requires work to fit!
With a 16" rim the lip is closer to the bump stop so you can't run as much backspace.
I have 18x10s with 6.25bs and had to use a bfh to get them to fit
With a 16" rim the lip is closer to the bump stop so you can't run as much backspace.
I have 18x10s with 6.25bs and had to use a bfh to get them to fit
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Well, as muchh as it would be cool to have them, I couldn't find a street tire wider than a 295 for them anyways. I can do that on my stock wheels, so I'm going to pass on them.
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Re: Maximum BS
Maximum BS....have you been talking to my girlfriend? LOL
I'm looking to run 18x10 on the back of my car....looks like 6.5" BS is the key, with a 295 tire.
I'm looking to run 18x10 on the back of my car....looks like 6.5" BS is the key, with a 295 tire.
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From: Bertram (outside Austin), TX
Car: 87 GTA
Engine: L98
Transmission: 700R4
Axle/Gears: Dana M78 3.27 posi
Re: Maximum BS
6.5" bs, on a stock 3rd gen width rear axle, is pushing. Guaranteed not a simple bolt-on, direct fit. I have 7" bs and had to cut a lot more than I expected.
6"bs would require minimal work, but still some. Use a 4th gen width axle & pretty much guaranteed a 100% direct-fit.
6"bs would require minimal work, but still some. Use a 4th gen width axle & pretty much guaranteed a 100% direct-fit.
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From: Trumbull CT
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Engine: 70/70 Turbo 5.3 LS
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Re: Maximum BS
i was able to fit a 17x10.5 mustang rim on mine with 6.8" BS. im running a ford 8.8 which is about 1.5" wider than a stock 9bolt on each side. i didnt have to clearance anything but i did hack off the bumpstop/bumpstop mounting bolts just to be safe. i have more than 1" of space. running no spacers
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