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Discussion Starter #1
Gonna shim my 70 to add more caster.. Read both sides of the fences on the knurled bolts vs. grade 8 shoulder bolt to even tack welding them in..

I want to go with the factory knurled style. Ive ordered thru McMaster-Carr over the years and i know you need to have all the specs of what you exactly want.

Im looking at installing from 3-4 washers per side so I need factory specs on diameter of threads, thread pitch, Coarse of Fine Threads, factory overall length, and length of shoulder/knurled part so i can order the correct bolts...

I DO NOT WANT TO HAVE TO REAM OUT THE BUSHING SHAFT or TACK WELD THE BOLD HEADS TO IT EITHER--- -- Just an FYI..........

Thanks
 

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Discussion Starter #2
i GOT THIS FAR I JUST NEED TO KNOW OVERALL FACTORY LENGTH OF KNURLED PORTION WITH THREADED END SO I CAN GET LONGER ONES.
 

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The factory bolt is 380459-S
Length under the head to the tip of the threads appears to be the stated 1 7/8"....... length of the threads is 13/16"
Therefore, the length of the bolt shank would be 1.0625"
Nowhere do I see the length of the knurls on the shank listed. It's probably somewhere around 1/2"-5/8"

ex-Global West GM
1991-1995
 

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Discussion Starter #5
I hate to start a new thread so I’m not going to. To make a long story hopefully not even longer,, what I want is to be able to dial in positive caster by putting in washers behind the front control arm bolts. Now on the other hand I don’t want the lower control arm binding so what I was wondering is there a lower control arm that will reduce that issue?

Global West, Open Tracker, etc...??

I also like some of the aftermarket strut rods however if some of you have been following my other threads I’m having trouble with the steering wheel not centering out of a turn and my SAI jacked up.

so I have 2 1/2 to 3° positive caster dialed in and I don’t have much more room to dial anymore in because the tires are going to then rub against the front valance on sharp turns.... Wheel still doesn’t like to return to center But everything I do seems to improve it a little bit..

if aftermarket control arms and strut rods will alleviate the problem then that’s the way I may go.
 

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Will 65-66 bolts fit?
Never tried it.
Those are 379329-S
1/2-20. 2 3/8" length overall under the head. 1 7/16" thread length. Bolt shank would be 0.9375"
(longer thread length because those are used with alignment shims from the factory)

ex-Global West GM
1991-1995
 

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To make a long story hopefully not even longer,, what I want is to be able to dial in positive caster by putting in washers behind the front control arm bolts. Now on the other hand I don’t want the lower control arm binding so what I was wondering is there a lower control arm that will reduce that issue?
Shimming the upper control arm won't bind the lower control arm.
 

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Discussion Starter #8
I am already at 3° if I put many more washers in there I believe it will
 

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Discussion Starter #10
Yeah but you’re talking 3° of caster now and then dialing in possibly three more because I’ve got a front end issue.

And you’re also looking at that lower control arm starting to bind on the camber alignment lower control arm eccentric bolt.

Who knows maybe I don’t know what the hell I’m talking about😀😀😜😜
 

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On the 65-66 cars Ford had a max on the number of shims, limited to maybe 9/16", I would be afraid to keep adding them
 

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Curious to know how much closer, if any, the front tire is moving to the front of the fender opening
 

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You may not want to hear this, because you want knurled bolts, but there is no reason you can't use grade 8 flange bolts. The only drawback to using flange bolts is that you have to hold the bolt from rotating while you tighten the nut so you have to contort yourself to hold one wrench on the bolt head and another wrench turning the nut or you can put a vise grip on the bolt head and the vise grip will hit something to stop it from turning while you tighten the nut. A lot of times, because of the flange on the bolt head it will not rotate as you tighten the nut because it has a lot of contact area. You can get serrated flange bolts too that will not turn.

The problems you're having were very common with a lot of my customers who called me about my adjustable LCAs or Adjustable Strut Arms (adjustable LCA and Start Rod in one product). The adjustability of the LCA allows you to reduce or eliminate the need for shims on the UCA except for camber and you don't have to move the tire out with a bunch of shims and then you now have fender interference. This along with slightly-shorter-than-stock adjustable UCAs that I built (using flange bolts I may add), that had +3 degrees of caster built into them allowed me to get 255s on the front of my 65 FB with nearly 5 degrees of caster and -1 degree of camber with no fender rub.

I shut my business down earlier this year during the COVID thing and I am probably not going to start it back up. It was PTP Engineering. I am retiring from aerospace in September also. I have been having some physical issues recently lately the worst being a pinched nerve in my neck that is causing severe pain in my left arm...pretty much puts my lifestyle on hold 'till I get better.

A lot of these old cars max out at about 2 degrees of caster when you are also trying to get -0.5 or -1 degrees of camber. With the adjustability, you could 5 to 6 degrees of caster and -1 degrees of camber no problem. Adjusting the length of the LCA does not in itself cause bump steer because when you change the length of the LCA, you also have to change the length of the steering arm to restore toe so the length of the LCA and the steering arm are the same as each other like from the factory and they don't have different arc lengths. Every car has bump steer...it's just about how much can you eliminate.
 

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I'm curious if anyone, especially someone with access to a lathe and mill, thought about making a billet upper control arm shaft that had enough "meat" around the bolt holes to slot the holes, maybe allowing 1/2-3/4" of movement fore and aft? Flanged bolts with inserts of different offsets would lock them in place. That would allow caster adjustment at the upper arm without affecting camber at the same time, like adding shims would.

Of course, adding a spherical bearing to the lower control arm inner mount and more adjustment on the strut rod would seem a more straightforward approach....
 

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I'm curious if anyone, especially someone with access to a lathe and mill, thought about making a billet upper control arm shaft that had enough "meat" around the bolt holes to slot the holes, maybe allowing 1/2-3/4" of movement fore and aft? Flanged bolts with inserts of different offsets would lock them in place. That would allow caster adjustment at the upper arm without affecting camber at the same time, like adding shims would.

Of course, adding a spherical bearing to the lower control arm inner mount and more adjustment on the strut rod would seem a more straightforward approach....
I considered this when designing uppers, but never went through with it due to risk of someone not tightening the bolts adequately. I agree with you that if they were properly tightened they would lock it in place especially if you used serrated flange bolts. There would be many 1000s of lbs of clamping force at those points. There are also camber plugs that fit into oval holes, but they were too big.
 
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