Modifying Currie control arms to double adjustable

[Mike_H]

As I was removing my single adjustable lower Currie control arms for the umpteenth time this weekend, I was really wishing I had some savvy double adjustable links. I even thought through what it would cost me to change em out, after selling the Curries, but reasoned that my time, while valuable, wasn't worth THAT much. So I finished my work and went on with life. This morning, in the shower, the thought hit me like a bus... Why can't I make my lowers double adjustable? I have a band saw, lathe, and mill at work too do the machining. I already have the required 1"-14 tap... All that is required is for me to buy 4 forged Johnny joints... For 60 dollars each. So, 240 dollars plus some of my time to upgrade to double adjustable links.

I really like the idea here, and will probably pull the trigger, unless someone knows of a good reason why it wouldn't work?

If I really got squirrelly, I could order some 7075 aluminum round stock and make some savvy knock offs.

EDIT: Even better...I can buy a bare housing and use the internals I already have!

https://www.rockjock4x4.com/CE-9113F-L-Johnny-Joint-Forged-End-1-in.-14-LH-Thread

 

[LJGreg]

Wouldn’t you need a counter clockwise tap?

 

[Mike_H]

Wouldn’t you need a counter clockwise tap?

Yes...You're right. The tap I have is RH. I'd need a LH tap...or have one of my guys set the lathe up and turn the threads for me...

 

[mrblaine]

As I was removing my single adjustable lower Currie control arms for the umpteenth time this weekend, I was really wishing I had some savvy double adjustable links. I even thought through what it would cost me to change em out, after selling the Curries, but reasoned that my time, while valuable, wasn't worth THAT much. So I finished my work and went on with life. This morning, in the shower, the thought hit me like a bus... Why can't I make my lowers double adjustable? I have a band saw, lathe, and mill at work too do the machining. I already have the required 1"-14 tap... All that is required is for me to buy 4 forged Johnny joints... For 60 dollars each. So, 240 dollars plus some of my time to upgrade to double adjustable links.

I really like the idea here, and will probably pull the trigger, unless someone knows of a good reason why it wouldn't work?

If I really got squirrelly, I could order some 7075 aluminum round stock and make some savvy knock offs.

EDIT: Even better...I can buy a bare housing and use the internals I already have!

https://www.rockjock4x4.com/CE-9113F-L-Johnny-Joint-Forged-End-1-in.-14-LH-Thread

I'd cut the barrel off and thread them in a heartbeat if I had the means. Boring bars work for that threading but they tend to chatter on a lot of the threaded bungs and arms I see. I know it hurts little but my feelings but I still don't like it.

I'd buy a very nice tap for that many.

 

[1904-06LJR]

Yes...You're right. The tap I have is RH. I'd need a LH tap...or have one of my guys set the lathe up and turn the threads for me...

But if you're doing this on a budget, would you REALLY need to? As long as you were ok with pulling a bolt, turning the joint to lengthen or shorten, then reinstalling the bolt is there a big deal with that?

 

[mrblaine]

But if you're doing this on a budget, would you REALLY need to? As long as you were ok with pulling a bolt, turning the joint to lengthen or shorten, then reinstalling the bolt is there a big deal with that?

Once you start dialing stuff in, DA are invaluable.

 

[Mike_H]

But if you're doing this on a budget, would you REALLY need to? As long as you were ok with pulling a bolt, turning the joint to lengthen or shorten, then reinstalling the bolt is there a big deal with that?

I thought that... Until I started dialing it in, like @mrblaine said. Once you have mini skids installed on the axle side lowers control arm brackets, it's not just one bolt, it's both. You have to jockey that arm back and forth to get it free enough to make the adjustment.

There is a reason savvy invests the money to make their arms double adjustable.

 

[Mike_H]

I'd cut the barrel off and thread them in a heartbeat if I had the means. Boring bars work for that threading but they tend to chatter on a lot of the threaded bungs and arms I see. I know it hurts little but my feelings but I still don't like it.

I'd buy a very nice tap for that many.

I have access to some pretty nice tooling, and I have three CNC lathes at my disposal (as long as production is satisfied). Plus some really good toolmakers on the payroll.

It is a small diameter and it has to go pretty deep... I'm more worried about deflection than chatter. I found that on my JKS bar... The threaded end wouldn't go as far as it should have, based on thread depth. I ran a tap into the bar and sure enough, after an inch or so, it started "cutting" threads.

 

[Trevlaw]

I have access to some pretty nice tooling, and I have three CNC lathes at my disposal (as long as production is satisfied). Plus some really good toolmakers on the payroll.

It is a small diameter and it has to go pretty deep... I'm more worried about deflection than chatter. I found that on my JKS bar... The threaded end wouldn't go as far as it should have, based on thread depth. I ran a tap into the bar and sure enough, after an inch or so, it started "cutting" threads.

If you have a decent lathe machinist, cutting that thread should be zero problem assuming you have the tooling and either a 3 jaw on the lathe or a big enough collet chuck to hold it with. Would only take me about 30 minutes to do one on the Mazak I used to run.

 

[Trevlaw]

You could also check with your shop to see if they have a 1" LH tap already, if not you can probably find a decent used or NOS one on ebay, you don't need anything special to get four arms done. Just make sure your CA is bored to the right ID with a nice chamfer and figure out a good way to start the tap straight. Probably chuck the arm up on a manual lathe, use a live or dead center, preferably a spring loaded center in the tailstock pushed up against the center drill mark on the end of the tap shank and spin the tap by hand a few turns to get it started

 

[1904-06LJR]

You have to jockey that arm back and forth to get it free enough to make the adjustment.

There is a reason savvy invests the money to make their arms double adjustable.

I definitely see what you mean. Twisting an arm is way easier. I was speaking purely with a budget in mind and not having to buy another tap.

 

[pagrey]

There is a reason savvy invests the money to make their arms double adjustable.

Is there really a large difference? Going from one to two is allot different than zero to one.

 

[mrblaine]

I have access to some pretty nice tooling, and I have three CNC lathes at my disposal (as long as production is satisfied). Plus some really good toolmakers on the payroll.

It is a small diameter and it has to go pretty deep... I'm more worried about deflection than chatter. I found that on my JKS bar... The threaded end wouldn't go as far as it should have, based on thread depth. I ran a tap into the bar and sure enough, after an inch or so, it started "cutting" threads.

Chatter, deflection, all caused by the same circumstance and only solved one way.

 

[mrblaine]

I thought that... Until I started dialing it in, like @mrblaine said. Once you have mini skids installed on the axle side lowers control arm brackets, it's not just one bolt, it's both. You have to jockey that arm back and forth to get it free enough to make the adjustment.

Even without the mini skids, when you adjust, invariably you wind up with the bolt hole pointed the opposite way so now you get to fuck with lining that back up with the mount. Nothing about single adjustable doesn't suck eventually.

There is a reason savvy invests the money to make their arms double adjustable.

Yes and no. The main reason is just how hard it is to weld steel barrels to aluminum rod. Since the arms had to be aluminum, that forced them to be DA. Not that there isn't enough benefit to justify the expense because there is but that wasn't why they are DA.

 

[Jezza]

If you thread your own bars I would put some flats on them as well. That is the one shortcoming of the Savvy arms in my opinion.

 

[mrblaine]

Is there really a large difference? Going from one to two is allot different than zero to one.

Massive difference. I despise single adjustable. Far too much work for even a single time adjusting an axle. With the double, you basically throw the axle under the rig on the ground. Scootch it sorta close front to back, side to side and if the arm won't reach, just screw it out longer until you can get both lowers in. Jack up one side a tad and get it on a short jack stand or blocks of wood, anything to hold it up so the uppers will sorta reach. Crank one out until you can get it in a mount, now you can jack it up and get it on stands.

Adjust both lowers to the same length, eyeball the pinion angle, start cycling. Takes but a few minutes to figure out where it needs to be and you don't have to pull a single bolt back out and fuck with lining it back up.

 

[mrblaine]

If you thread your own bars I would put some flats on them as well. That is the one shortcoming of the Savvy arms in my opinion.

Not really.

 

[mrblaine]

You could also check with your shop to see if they have a 1" LH tap already, if not you can probably find a decent used or NOS one on ebay, you don't need anything special to get four arms done. Just make sure your CA is bored to the right ID with a nice chamfer and figure out a good way to start the tap straight. Probably chuck the arm up on a manual lathe, use a live or dead center, preferably a spring loaded center in the tailstock pushed up against the center drill mark on the end of the tap shank and spin the tap by hand a few turns to get it started

Takes a fair bit of horsepower to run a 1" tap in for steel.

 

[pagrey]

Massive difference. I despise single adjustable.

I totally agree with everything you said. Just saying once you can thread one end doing the other is easy as far as production goes. For a novice threading that first joint is a total bitch so zero to one is a huge step. I wasn't even remotely discussing the bennifits of double adjustable, I'm on board with that.

 

[mrblaine]

Is there really a large difference? Going from one to two is allot different than zero to one.

I totally agree with everything you said. Just saying once you can thread one end doing the other is easy as far as production goes. For a novice threading that first joint is a total bitch so zero to one is a huge step. I wasn't even remotely discussing the bennifits of double adjustable, I'm on board with that.

I don't see where you said that the first time. Try some fucking context next time.