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Old 01-20-2018, 10:08 PM
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Neil B
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Originally Posted by DIY-79
It’s very close. It’s something I too am concerned about. The tighter the bolts are screwed the flatter the spring became. I’m hoping I’m past the 1/2” recomended offset between the upper u-joint and lower u-joint and can loosen the nuts some. Monday a lot of questions will be answered.
My halfshafts are level with an 8 inch bolt showing 3/4" of threads below the lock nut. That's with a VBP 360 spring.
Old 01-21-2018, 10:15 AM
  #22  
DIY-79
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Maybe my suspension needs to settle. I haven’t driven it yet. I was just happy that both sides were equal. The shocks were dialed in at 10 clicks. Maybe I need to drop to 0, let it settle and then dial them back up.
Old 01-21-2018, 01:19 PM
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Originally Posted by DIY-79
Very nice. I’m going to go with the Rival S also. What backaspaing you running. When I pulled the c clips I slipped the side yokes out until I had about an 1/8” still past the spider gears. That allowed about 1/3” of side yoke outside the diff. Should translate to a bit more room. I took a piece of flat steel and drilled a hole in it and I I mount it on the rotor. Then I can spin it around and measure to the frame to get my max BS. I’ve been crunching numbers using specs from Tire Trac to find total backspacing (backspacing of the wheel + overhang of the tire).
Im running 18x12.5 wheels with 5.25 backspacing.
Old 01-21-2018, 01:42 PM
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That’s awesome. Looks your fenders are stock too. What size tire? I’m looking at a Weld S77 11 x 18 with 5.2” or 5.6” backspacing. By my calculations a 315/30R18 should fit. I came up with an equation to figure the total backspacing of the tire and wheel together.

(Section Width - Wheel Size) / 2 + Backspacing

so for the Rival S

(12.6 - 11)/ 2 + 5.2 = 6” Total BS

or

(12.6 - 11) / 2 + 5.6 = 6.4” Total BS

then add whatever clearance you want to run. 1/4” or 1/2”.
Old 01-21-2018, 01:58 PM
  #25  
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Originally Posted by DIY-79
That’s awesome. Looks your fenders are stock too. What size tire? I’m looking at a Weld S77 11 x 18 with 5.2” or 5.6” backspacing. By my calculations a 315/30R18 should fit. I came up with an equation to figure the total backspacing of the tire and wheel together.

(Section Width - Wheel Size) / 2 + Backspacing

so for the Rival S

(12.6 - 11)/ 2 + 5.2 = 6” Total BS

or

(12.6 - 11) / 2 + 5.6 = 6.4” Total BS

then add whatever clearance you want to run. 1/4” or 1/2”.
My fenders are flared. I'm running 335-30-18s on a 12.5 wheel.
Old 01-21-2018, 02:07 PM
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That makes more since. Camera angles are deceiving. Looks awesome. There’s a car in the big tire combo thread that’s running 315’s on 10” wheels with no flairs. 5.25” BS. That’s where I got my inspiration. The tires will stick out of the fenders but I have a 420lb spring and will be running QA’s at 10 or higher. Did you try to match the tread width of the tire to the wheel size? I’ve read that a key to getting as much of the tread width to ground contact as possible. The wheel should be a 1/2” either direction of the tread width with the same being optimal. Section width doesn’t matter except for BS purposes.
Old 01-21-2018, 04:20 PM
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Originally Posted by DIY-79
That’s awesome. Looks your fenders are stock too. What size tire? I’m looking at a Weld S77 11 x 18 with 5.2” or 5.6” backspacing. By my calculations a 315/30R18 should fit. I came up with an equation to figure the total backspacing of the tire and wheel together.

(Section Width - Wheel Size) / 2 + Backspacing

so for the Rival S

(12.6 - 11)/ 2 + 5.2 = 6” Total BS

or

(12.6 - 11) / 2 + 5.6 = 6.4” Total BS

then add whatever clearance you want to run. 1/4” or 1/2”.
Don't forget that an 11" wheel is actually 12" wide lip-to-lip.
Old 01-21-2018, 04:57 PM
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Originally Posted by Neil B
Don't forget that an 11" wheel is actually 12" wide lip-to-lip.
You just reminded me of that. I knew I was forgetting something. I had laid one of my current wheel/tire combos on the ground and did the math and was coming up with less BS than the equation was giving me. I've been brainstorming for the answer. This is why BS and offset are different. I learned all that once and had forgotten it. Increasing the wheel width by 1" actually makes for less total backspacing. I can't wait to see how much actual BS the car has tomorrow. A 11.5' wheel with 5.6" BS should fit. I don't think a lot of people understand that when you increase wheel width it drives the wheel and tire away from the frame for a wheel with the same BS. Also, section width decreases by .2" for every 1/2" wider you go over what the original section width was determined to be. IE: Section width of 10.5" measured on 10" wheel decreases to a section width of 10.3" on a 10.5" wheel, or 10.1" on an 11" wheel. I got this info from Tire Rack who measures all their tires and posts the results.
Old 01-22-2018, 01:12 AM
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You got that backwards. Section width increases ~0.2" for every 0.5" increase in wheel width.
Old 01-22-2018, 07:11 AM
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Originally Posted by Metalhead140
You got that backwards. Section width increases ~0.2" for every 0.5" increase in wheel width.
Double checked Tire Rack. Your right. That’s two bits of info in this thread I had wrong. I’m starting to question who my real father is.
Old 01-22-2018, 03:01 PM
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Old 01-22-2018, 03:09 PM
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Neil B, Gordonm, as you can see the upper hem will hit the bump stop bracket. The trailing arm simultaneously hits the rubber stopper. The rubber bump stop compressed enough to allow contact. A 1/2” spacer would work or I can clearly see that grinding out the part of the bracket that it’s hitting would work also. I’ll slap back together, bleed the brakes and drive it as is to see if it hits for me. I’m running a 420 lb spring and the QA’s will be set to 10ish. I’ll adjust from there.

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Old 01-22-2018, 04:24 PM
  #33  
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Originally Posted by DIY-79
Neil B, Gordonm, as you can see the upper hem will hit the bump stop bracket. The trailing arm simultaneously hits the rubber stopper. The rubber bump stop compressed enough to allow contact. A 1/2” spacer would work or I can clearly see that grinding out the part of the bracket that it’s hitting would work also. I’ll slap back together, bleed the brakes and drive it as is to see if it hits for me. I’m running a 420 lb spring and the QA’s will be set to 10ish. I’ll adjust from there.
Mine is exactly the same way. Removing the back side of the bump stop bracket would solve the problem however the upper strut rod may then contact the floor or be very very close. My shock length is 10.5 inches when the upper heim bottoms out. The shock itself bottoms at 10 inches, so we're not talking much here.
Old 01-22-2018, 05:28 PM
  #34  
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Mine looks like it will only continue up into the actual frame. I’ll check closer to see if I think it will dig into the fiberglass floor. I’m gravity bleeding the brakes as I set the rear toe. I used the center hole of the rear crossmember (not the diff crossmember) as my center point and measured to the backside of the trailing arm to get the lower strut rods set so the rear of the trailing arms are the same distance from the frame centerline. Now I’m setting toe to 0. The camber is already set to 0°. Hopefully I’ll be able to get the rear wheels centered to the frame. Then I’ll use the string method to track the front wheels to the rear. Does this sound like a good plan????
Old 01-22-2018, 06:01 PM
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Made plumb bobs and dropped them from the center holes in the frame. The specs I have of the frame show those holes as indexed and used for measuring. Now I can set the toe off the line. I used fishing line and what you can’t tell from the picture is the laser illuminates the fishing line when it’s lined up. I wasn’t expecting that, but it made lining the two plumb bobs up a piece of cake.
Old 01-22-2018, 06:05 PM
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Both sides mirror each other and are same lengths, same angles and same distance from the floor. I’ll check the rear against the laser line and make any fine adjustments using the lower strut rods. Then dial in the toe. Does anyone see any problems with this?????
Old 01-22-2018, 06:38 PM
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Originally Posted by DIY-79
Mine looks like it will only continue up into the actual frame. I’ll check closer to see if I think it will dig into the fiberglass floor. I’m gravity bleeding the brakes as I set the rear toe. I used the center hole of the rear crossmember (not the diff crossmember) as my center point and measured to the backside of the trailing arm to get the lower strut rods set so the rear of the trailing arms are the same distance from the frame centerline. Now I’m setting toe to 0. The camber is already set to 0°. Hopefully I’ll be able to get the rear wheels centered to the frame. Then I’ll use the string method to track the front wheels to the rear. Does this sound like a good plan????
Mine looks like the strut will reach the floor before the outer heim reaches the frame. Im currently looking for ways to reduce the stack height of the heim. This will introduce some camber gain but I'm ok with that.

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Old 01-22-2018, 07:05 PM
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Originally Posted by DIY-79
Both sides mirror each other and are same lengths, same angles and same distance from the floor. I’ll check the rear against the laser line and make any fine adjustments using the lower strut rods. Then dial in the toe. Does anyone see any problems with this?????
I usually set the toe with a simple tow bar/gauge. Once toe is where I want it, I use a laser to line up the rear wheels with the front. I shoot a laser from a straightedge along the rear wheel to a fixed point outside of the front spindle. I usually use an index card taped to a jack stand. I adjust toe equally(opposite) on both sides until the laser is equal distance from the front spindle on each side. If this is right, I don't think the relationship between the trailing arms and the frame centerline matters.
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Old 01-22-2018, 10:39 PM
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Originally Posted by Neil B
I usually set the toe with a simple tow bar/gauge. Once toe is where I want it, I use a laser to line up the rear wheels with the front. I shoot a laser from a straightedge along the rear wheel to a fixed point outside of the front spindle. I usually use an index card taped to a jack stand. I adjust toe equally(opposite) on both sides until the laser is equal distance from the front spindle on each side. If this is right, I don't think the relationship between the trailing arms and the frame centerline matters.
My brain won’t let me not try to index the wheels to the frame. You may be right and it may not matter all that much, as long as the rear tires and front track track the same. I just have to try. I got the toe just shy of 1/8 of an inch. I was able to take her for a drive and she’s very solid. I took the power steering off when I rebuilt the front end. All I have left suspension wise is a spreader bar for the front and tweak the sway bars. I’m waiting to see if I have under or over steer. Then wheels and tires.
Old 01-22-2018, 10:43 PM
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Originally Posted by DIY-79



You're actually going to run your outer u-joint bolts without some sort of locking mechanism like french locks or lock washers?
Just saying.........


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