521 Ball Joint Mod

[Juanjoze]

 

Hello, first of all I would like to thank this community, because I found a lot of information and inspiration to modify my truck by myself.

I would also like to thank a friend from the Datsun community in Mexico who shared his experience making the modification.

 

Parts that were used.

- LCA From Datsun 720.

- LCA Bushing From Datsun 720.

- LCA Torsion bar Anchor and Sun Bolt (Lower Control Arm Bolt) from 720.

- Torsion Bars and Rear Anchor from 521.

- Spindle and Hub from Datsun 720.

- Brake Disck, Calipers, Brake Hose from Datsun 720.

- UCA From Chevrolet Luv 95-05 From Mexico, ISUZU pick up USA.

- Datsun 620 Strut Rod or Tension Rod. Heim Joints.

 

How to.

- Remove LCA, UCA, Tension Rod, Brake Hose from truck.

- Optional: Remove the LCA bushing or use flat washers to fill the new LCA gap. First problem, if you mount a newer 720 LCA hub to fit the gap in the control arm perfectly, the torsion bars push back almost 3/8", I have to re-drill the bracket mounting holes of the rear torque arm to pick it up.

-Drill the upper ball joint hole on the spindle to take the wider isuzu ball joint.

 

 

 

 

 

 

 

 

[]2eDeYe]

Nice solution. Looks great, thanks for sharing. 🙂

[Stoffregen Motorsports]

Nice clean work.

[thisismatt]

Looks good. Aligned it professionally yet? Results?

[greenthumb]

Standard 521 tie rods and Center link?

[Juanjoze]

7 hours ago, thisismatt said:

Looks good. Aligned it professionally yet? Results?

Not yet, I will update the results this week.

[Juanjoze]

Just now, greenthumb said:

Standard 521 tie rods and Center link?

 

- Standar 521 Center Link.

- 720 - Hardbody Tie Rods.

 

[uberkevin]

This is intriguing. 

Thanks for sharing the info you've found so far. 

[thisismatt]

1 hour ago, Juanjoze said:

Not yet, I will update the results this week.

Cool, thanks.  Just noticed your TC rod bolt at the heim isn't reaching the nyloc portion, but maybe you fixed that already

[Juanjoze]

Just now, thisismatt said:

Cool, thanks.  Just noticed your TC rod bolt at the heim isn't reaching the nyloc portion, but maybe you fixed that already

Thanks, that was my last mockup before tightening the nuts.

[pidge]

That’s pretty cool. Some pretty neat idea you’ve got going on. 👍👍👍 Aren’t the holes in the top of  spindle tapered or am I thinking wrong? I spose you could get lowering spindles if they stilll make them. Dose it fit 14” wheels still? I love the idea and keep us posted. 
-Pidge

[NC85ST]

If it’s basically all 720 stuff, then a 14” wheel shouldn’t have a problem fitting. Two wheel drive 720 wheels were 14” from the factory.

[uberkevin]

Man there's an 81 720 in a yard near me, im tempted to start pulling parts from it..

[Wildcat Walker]

Need to see alignment sheet. And pictures of wheel centered in fender. If this works, great information. 

[Juanjoze]

1 hour ago, NC85ST said:

If it’s basically all 720 stuff, then a 14” wheel shouldn’t have a problem fitting. Two wheel drive 720 wheels were 14” from the factory.

Hi, stock 521 wheels, will not fit, because hub wheel bore, but 720 14 steel wheels fit perfect. 

[Juanjoze]

 

Not everything went so smoothly, the previous owner somehow bent the shock towers.

Camber was almost +2.5 degrees, I used almost 3/4 inch on shims.

 

I don't know what would be better, cut the upper control arms to reduce camber or keep the shims, what do you think?

[Juanjoze]

9 minutes ago, Wildcat Walker said:

Need to see alignment sheet. And pictures of wheel centered in fender. If this works, great information. 

 

Sorry friend, the only lineup available in my town is with classic Camber Caster Gauge. i will Post some pics.

[Juanjoze]

7 hours ago, pidge said:

That’s pretty cool. Some pretty neat idea you’ve got going on. 👍👍👍 Aren’t the holes in the top of  spindle tapered or am I thinking wrong? I spose you could get lowering spindles if they stilll make them. Dose it fit 14” wheels still? I love the idea and keep us posted. 
-Pidge

Yes, you're right, it takes some day with a dremel and a lot of patience, basically I was cutting and checking the seat of the ball joint with ink. The tip of sandpaper and Aluminum Oxide Grinding Stone worked better for me. 

[Juanjoze]

 

[thisismatt]

Can also get the correct tapered reamer 👍

[Juanjoze]

Just now, thisismatt said:

Can also get the correct tapered reamer 👍

Even get they Dremel Aluminum Oxide Grinding Stone was really hard in My Town, But a reamer will be great. 

[d.p]

OP makes this sound so simple….  Is everything after ”Remove….”  Optional? 

 

How to.

- Remove LCA, UCA, Tension Rod, Brake Hose from truck.

- Optional: Remove the LCA bushing or use flat washers to fill the new LCA gap. First problem, if you mount a newer 720 LCA hub to fit the gap in the control arm perfectly, the torsion bars push back almost 3/8", I have to re-drill the bracket mounting holes of the rear torque arm to pick it up.

-Drill the upper ball joint hole on the spindle to take the wider isuzu ball joint.

[Juanjoze]

Optional 

Just lower control arm bush is optional, and if you go that way, it's necessary to adjust the rear bracket where the torsion bars are anchored.

 

Implicit: 

- Change brake hoses.

- Change the terminal of the rigid brake lines from 3/8 to 10mm fittings.

- Drill spindles upper ball joint hole.

- Drill upper control arms mount holes to 14mm or 9/16.

- Get shims ando 9/16nf x 4" grade 8 bolts.

- Front tensión rods, I used heim joints, you could solder the 720 mounts.

- Replace Master Cylinder from single to.dual.

 

I'm just testing, so far it works fine.

 

[pidge]

Love it

[datzenmike]

The 521 loves you for this. Probably would work on the 620???