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Old 01-13-2017, 12:51 AM   #26
SkinnyG
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Re: Upper link bar angle

You will have ~some~ pinion change because your upper and lower link arms are not the same length. If they were the same length, the pinion angle shouldn't change at all.

Just optimize the pinion angle for whatever ride height you will run the most. Other heights will be a compromise (good thing you made it adjustable *big*grin*)
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Old 01-13-2017, 02:15 PM   #27
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Re: Upper link bar angle

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Originally Posted by Garagely5150 View Post
I tried to match the pinion angles. I was told 3* is optimal. But all I could get out of my tranz is 8* if I jacked up the tranz any more it was putting a lot of stress on my motor mounts. So I made my axle 8* as well but I just articulated my axle up about 10 inches and put it back down and it seems to be ok but after I checked my axle pinion angle again it's more like 7* and when I cycled it up the pinion angle dropped to 0 at 10 inches high
I would rework your motor mounts to correct that angle a bit. You could pie cut the front of your mounts and raise the trans then weld them back together. Check your clearance between your oil pan and rack and pinion.

How do you plan to get 10 inches of travel up? Bag on bar? That is a lot of travel and could result in a harsh ride with the needed pressure to get there.

I would install my notches now to see the actual angles of everything as you are kinda working opposite. I would also shorten the lower bars in order to minimize the change in pinion angle.

Lastly, from a visually pleasing perspective I would rework the upper front link tabs to make them "flow" better.

Hope this helps.
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Old 01-13-2017, 11:59 PM   #28
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Re: Upper link bar angle

I was just cycling it and I jacked he frame up 10 inches. Not planning on going that high. It's not notched so I can only cycle it one way to check for binds. I am gonna put a gusset up the upper tabs it's not ideal but should work. I don't really know what else to do there. That's where the bars fall.... I should shorten the lowers bars huh? Cuz I was told longer the better and I didn't cut any of them. I read the top bars should be 70% of the lowers
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Old 01-15-2017, 04:25 AM   #29
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Re: Upper link bar angle

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Originally Posted by Garagely5150 View Post
I was just cycling it and I jacked he frame up 10 inches. Not planning on going that high. It's not notched so I can only cycle it one way to check for binds. I am gonna put a gusset up the upper tabs it's not ideal but should work. I don't really know what else to do there. That's where the bars fall.... I should shorten the lowers bars huh? Cuz I was told longer the better and I didn't cut any of them. I read the top bars should be 70% of the lowers
I assume you are going to go a lot further down than the 10 inches you went up. Since your upper links are tacked in you already know where your holes are. I would cut up some construction paper and play with the shape a bit until you find something you like. I think a tab that has a 90 degree angle cut into the bottom that spans the upper and side of your cross member would look good. You will need to cut them and drill them yourself. If that doesnt make sense let me know and I will use my crappy paint skills to draw something.

Longer is better to a point. The 70% thing isnt really correct and I would say that your upper bars should be AT LEAST that long. You can make them longer (or lower bars shorter).
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Old 01-15-2017, 01:29 PM   #30
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Re: Upper link bar angle

When designing a short-long-arm "double wishbone" suspension for front suspension, a 70% upper arm is a reasonable ball park (but there is a lot more to it than that).

On a rear suspension, upper arms are only short because there is usually a back seat there.
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Old 02-05-2017, 10:46 PM   #31
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Re: Upper link bar angle

Redid my upper bars. Found my instant center. Now my upper bars would intersect with the lowers in front of the bumper. If they kept going obviously
.. also I decided to back half it bc there was a lot of pitting on the rear rails.
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Old 02-05-2017, 10:49 PM   #32
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Re: Upper link bar angle

Back half removed
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Old 02-05-2017, 10:59 PM   #33
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Re: Upper link bar angle

Reworked upper bar tabs. Back half cut off
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Old 02-06-2017, 02:55 PM   #34
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Re: Upper link bar angle

Bars and tabs look a lot better.
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Used parts build: http://67-72chevytrucks.com/vboard/s...d.php?t=638991
My brother's Nova: http://www.67-72chevytrucks.com/vboa...d.php?t=727985
Rear suspension rework: http://www.67-72chevytrucks.com/vboa...d.php?t=750557
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Old 02-13-2017, 05:35 AM   #35
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Re: Upper link bar angle

TRIANGULATED REAR 4-LINK ASSEMBLY
AND INSTALLATION TIPS

https://assets.adobe.com/link/17afad..._public&page=3
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