Thought I'd post some pics of the adjustable torque arm and cross member I just fabricated.

The arm is from 0.156" 1025 steel DOM tubing.
Rear axle bracket from 0.25" plate.
Adjusting coupler (3/4") and solid rod ends from SW racecars.
Crossmember from 1.5"x2"x0.125" HSS.
Safety loop from 6" sch40 stainless pipe (0.28" thk).

I had it installed for this past weekend at Luskville, it didn't make a difference. I am suspecting that since the track was so bad it would be hard to tell.

 

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You spent how much time on that, how much money, you pay for Mobil 1 for your car(s)- and you left that muffler strap safety loop there?

 

What?

 

Your first pic- your safety loop looks like its made out of a rusted piece of leftover muffler hanger.

 

I am sorry that you can't read.

 

Notice the smiley in my first post ( )- I'm getting the idea your getting upset over this?

 

No man, just thought you were serious...guess I should have painted it eh?

It took about 30hrs and about 6 zip cuts.

 

Looks pretty good to me. Now you have to come back down here to teach me how to weld and fab up something like that. Bought a mig welder last week but have been so sick with some freakin' virus, I haven't even struck an arc with it yet.

I would hope it did make a difference but the bumpy track made it seem as it didn't. What did you set your pinion ange at?

 

Ya, Luskville is brutal. The shutdown area is comparable to a gravel road. The track is pretty flat though. The launch area was unprepped, so unless you had slicks it was a joke!

I ran at Grand-bend once. You could dump the clutch at 4000 and not spin on street tires.

I had the pinion set at -2º form the driveshaft at ride-height.

Now it's time for at least drag radials with this and the 9-bolts(s).
I'm leaving about 1/2 second on the table during the first 60 feet.

Did you get a gas MIG?

 

Likely will have to play with the pinion angle a bit.

Yes I got gas and even hooked it all up. Argon/CO2 mix. Med tank. Think it's 5 cubic meteres. $55 lease for a year and $45 for every fill/exchange. Is that ok for a price or could I have done better? I know it's much better than the scammers over at BOC was offering. I have a long story to write about those ****** if I ever get the energy to type it out.

 

That sounds about right for the gas.

I actually don't have a welder, borrowed one from a buddy. It used the Argon/CO2 mix as well, and 0.023" wire. He does mostly body work with it and helped with some of the welding as I didn't want to risk learning on a torque arm!

I can give you sketches of the brackets for the axle if you're up for fabbing one. The tubing is threaded directly (no inserts) for the 3/4-20 rod ends, one LH, one RH.

 

I'm in no rush to put one together or even start one from scratch being as green as I am right now but wouldn't mind going after something like that after I get some experence. If you have some time later to put together a sketch, I and I'm sure others would make good use of it.

 

Do you know the Argon/CO2 mix percentage? If i remeber it right from school the higher the CO2 the hotter the arc will burn.


Cool looking fab work I really need to spend the time doing that stuff myself.

 

Hey thanks man,

I have no idea about the gas...

 

75/25 is the ratio. As far as I knew, which isn't much, all it did was provide a shield for the molten steel. What really sucks is I need a different tank of shielding gas for stainless and another one for allum.

 

Yup, it basically keeps the air (Oxygen/Nitrogen) from the molten metal as it will absorb it very quickly and weaken it.

Same as the flux coating on a stick welding rod except in gas form.

 

Oh your running argoshield 25C..that should work for stainless,you just need the stainless wire and a different wire brush so you dont contaminate the steel.

When i was in school we used to experiment with different wire and covering gas mixtures to see the reaction of the arc.

 

Nice Fabricating work Well Done

 

Hum… Looking at the pictures raises all sorts of questions…

- what dimension of the tubing is .156”, the wall thickness? What diameter is it?
- What bushings did you use?
- By “solid rod ends” I’m assuming that you mean the ones without the spherical bearings, right?
- Are they threaded right into the tube or did you use the weld in/on threaded ends?
- What did you end up with for an overall length?
- Do you have any more/better pictures of the setup?
- Now that you’ve had it for a year and a half, how is it working? Would you do anything differently?

 

This should clarify:
The arm is from 0.156" wall thickness x 1" OD (outside diameter) 1025 (steel grade, 0.25% carbon) steel DOM (drawn over mandrel) tubing. I bought 10ft and it was JUST enough.
Rear axle bracket from 0.25" plate.
Adjusting coupler (3/4") and solid rod ends from SW racecars
**Here are all the part number from SW including jam nuts etc
#40-235 [2x rod ends, solid means no spherical bearings, these things get locked solid and don't rotate, so spherical bearing make the joints weaker]
#65-120/65-121 jam nuts, LH and RH thread.
#65-1001 hex adjuster
#65-T750-L Left Hand Tap (for directly threading the tubing, ie no welding inserts)
#65-T750-R Right Hand Tap (for directly threading the tubing, ie no welding inserts) I remember the threads were a bitch to start, I had to drill the tube out to a slightly larger ID to start the taps using I think a 5/8 drill.
Total cost was $107.72 with shipping, parts are very good quality.
Bushings were polyurethane from Energy Suspension, I don't have the PN. They are right out of the catalogue and cost about $20. They came with a sleeve for 1/2" bolts you see and fit into the tubing welded to the cross member tightly. Use grade 8 fasteners. The stock long axle bolts work if you use thinner washers..

Overall I don't know how long it is, I made this this thing shorter to fit in with the T56 in there, so it depends on if you're using a shorter trans and wahat xmember etc. A few inches longer or shorter won't change much. I also would make another the exact same, no changes. I'm not sure how much a difference it made as after getting it to the track with the DR's the clutch was limiting my short times. I think it is fixed now, so I'll have to wait and see what it's like this year.
Take a look at what all the manufacturers are making their arms with..
SW has a nice simple one that I liked, almost the same as mine ended up.
Good luck with the fabrication.

 

What did you end up making the sleeves for the bushings out of?