Heim joint

3/4" is your best bet.

Mark, what size you use depends on the design of your control arms. You can either put two rod ends on the inboard side, to replace the bushings, or you can use a single rod end on the outboard side, which replaces the upper ball joint. On the inboard side, you'd probably use 1/2" rod ends.

The use of heims in suspensions is usually limited to racecars-only, for two reasons
1)- the constant pounding of street driving with zero maintenance distorts & wears loaded bearing surfaces if the heims you choose has them. Two-piece all-metal ones might have longer lives than those with teflon or bronze liners. Pay close attention to the way your car feels each time you drive and be prepared to change the heims regularly when an inspection shows looseness. Heims are NOT repairarable.

2)- dirt, water, road-swarf etc gets inside and causes binding & more wear. There are heim-seals specific to each size that can help this. Speedway racing in NE or Pegasus Auto Racing in WI both sell these seals very cheaply.

The main Pantera vendors sell these a-arms and use very heavy-wall tubing in their builds- often of 4130 steel. Tricky to weld & hard to bend. Don't be surprised if your fabrication weighs more than the entirely adequate stock a-arms. A journeyman welder should be doing this work- your life depends on the integrity of the welds (and threads). Good luck.

6018 has heim joints on the upper suspension arms both front & rear. A previous owner had installed control arms which were modified (front) or manufactured (rear) by Ron Siple. The control arms have two heim joints each, replacing the eyelets where the rubber bushings were pressed-in. The control arms pivot up and down on the heim joints, which takes some of the unwanted movement out of the suspension, makes the camber and toe more consistent, and response to driver input is razor sharp. Pivoting on heim joints also makes the suspension more plush over bumps (eliminates the resistance to movement which rubber bushings have). So there's an upside (improved handling and improved plushness) and a downside (increased harshness on poor road surfaces).

Here's the dimensions ...

I appreciate all the input. Currently 90% of my driving is ORR's and track days. Too easy to get into trouble on the roads.

While I have the facilities to make everything, I am not a welder. I'll just tack the pieces in place and then take them to a certified welder.

Thanks,
Mark

You don't really need them and if you convert the rubber bushings to polyurethane with stainless inserts, the heims are a down-grade.

I have used them, heims, on trailing arms (toe in rods) on IRS cars replacing the stamped steel trash with 1" od 3/16" wall DOM steel tubes.

Those use 3/4" left and right threaded tubes. That is as small as I would go on anything. That is the sizing needed to replace the bolts provided by the car manufacturer. That's on little 4 bangers with skinny tires and intended for everyday street driving in an economy car.

How does someone come up with using 1/2" for competition? Put away your slide rule and use your common sense?

They will stay tight for about 500 miles then they start to rattle.

You could use the Jeep style that are intended for vehicle suspensions but have rubber inserts instead of Teflon.

My opinion of course which on the Pantera is don't bother. There is nothing to be gained, only lost.

"We" found a company that actually made nice extruded tubing arms for this application. All nice powder coated black, threaded and knurled. They failed withing 20 miles.

The company bad-mouthed my solution only to have their arms fail by pulling out the heims and bending the arms.

Mine are ugly but they are still going, albeit with rattles?

You need to KNOW exactly what you are doing with this stuff. If you are dead, you won't get as much fun out of driving your car? I have other plans. Everyone is free whatever they choose?

You have to know where to stop modifying the car. Heims are over the limit.



Detomaso started as a race car builder really. He/they know how to build a suspension.

As Bosswrench has mentioned, it is very difficult to improve upon the stock suspension arms on this car.

Likely they will be heavier and they certainly will not have the proven durability of the stock arms.

The aluminum billet arms are actually heavier and their durability is questionable.

The rod ends Ron Siple uses in his upper control arms have load ratings of 19,500 lbs (1/2") and 21,900 lbs (5/8"). They are Teflon lined, mil-spec, Aurora's. According to Siple, they are far stronger than the suspension mount structure they are bolted to. As an Engineer, he's done the calculations and knows what's suitable for the application. I personally know people who have been using these in their Pantera's for more than a decade (including George P.) without an issue and without having to replace a single rod end.

That is a wonderful thing. Everyone is happy.

Mark, my track only Pantera was set up by EJ Trivette and all suspension have .75 threaded rod ends into 1.0 OD threaded rods with .50 grade 8 bolts. After about 6 years of track use he is getting ready to replace all of them and the shocks (all from QA1) and realign and balance car. It is not cheap to run a track car!
Good Luck, Dave A.