944 IRS conversion

[oprn]

I know that conventionally a jig is used to place and weld the inner pivot when doing this conversion. Is there any reason why the actual control arm could not be used instead?
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[b-man]

Think about it.

Would you trust that bolting the arm up with all the play in the mounting bolt holes would accurately locate the pivot point?

That’s why everyone uses a jig.
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1956 Dove Blue Panel
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[oprn]

The jig doesn’t use bolts?

Just asking as I have not done this before and do not have a jig in hand.

Also can this be done with the body in place?
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Our cars get old, we get old but driving an old VW never gets old!

[BFB]

Well not just the play in those bolt holes but also the pivot point in the torsion housing and flex in the plate.
The jig is welded solid and bolts to the 4 bolts at the end of the torsion tube and even at that there’s still some room for error. The first one i did i cut out the engine frame horns way more than i needed. Id hate to try and convert one without the jig, not that it’s not doable but even with the jig there’s some guesswork. Jig is well worth the money
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[oprn]

Thanks. I will see where the nearest jig is and the cost to get it here. Is there a right and left or does one jig do both sides?
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Our cars get old, we get old but driving an old VW never gets old!

[Wreck]

The one time I did this job I didn’t use a jig , an old panel beater gave me a series of measurements where to put the bracket , I did it with the body on .
His measurements were spot on , verified later on a 4 head wheel align machine .
I wish I still had those measurements !!

[joemama]

Yes, there is a left and right. A slow tedious job. Youll end up taking the jig on and off many times. If you go to pacificcustoms.com, and click on information for IRS pivot for stock torsion housing, towards the bottom of that page you will find a link to an article with instructions. They also sell the jig, so you can see what it looks like.

[oprn]

Appears to be nothing available locally. Several sites (Pacific Customs is one of them) in the USA have them in the $85 - $98 range but with shipping and customs etc. it comes to $495 CDN!

Ya! A little steep don't you think?

Looking at the pictures they look very simple to build, that is an option. Just a bit of square tubing, some flat plate and a couple sizes of pipe. Jug it all up on the doner car, weld it and Bob's your uncle!

I put a wanted ad on the local VW Face-Plant site so... maybe someone has a set.
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Our cars get old, we get old but driving an old VW never gets old!

[Clatter]

Ah, man i sold a set I had a couple months ago…
They’re out there.

They’re easy enough to make if you have a donor IRS car without the arms in to measure from.

You also don’t need curved bar to build them.
They can be pieces of straight stock cut at the right length/angles.

Finding a couple small lengths of pipe/tube that locate tightly off of the pivot bolt would be the hardest part.
Unless you have a lathe of course..
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[RickS]

I built a throwaway set when I did a conversion on a lowlight Ghia. I just used some angle iron and the old spring plate covers. Worked well.

While you’re at it, narrow the control,arms also and put a bigger tire under the fender!

[oprn]

Yes Clatter, I do have a lathe.

Thanks for the pictures RickS! That is about what I had in mind, good to see that yours worked. As for narrowing the control arms... well, Hmmm...

You see, the thing is my doner car is a '86 944 with the wider aluminum control arms. My '83 944 has the narrow steel ones that I think are the same width as the Beetle. So ideally I would put the aluminum ones in the '83 and the ones from the '83 in the Buggy. That means having 3 cars ripped apart to do this IRS conversion...

As for wider tires, I had 215's in mind for the rear or at the very most 235's. Looking for road handling and mileage over looks.
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Our cars get old, we get old but driving an old VW never gets old!

[drumbum68]

If you are setting up for stock height, I guess a jig works. If you are raising for offroad, I prefer to use the (straight) arms I am going to build with, so that I can dial in the camber I want.

I would think the same would apply for lowering.

YMMV

[RickS]

[Marcus Vinicius]

[oprn]

An update on this thread is in order. I bought a set of EMPI jigs and after much trimming, fitting and welding I cleaned up a control arm and mounted it along with a wheel on the Buggy.

Well sir, that was a complete failure! That rear tire now has about 3.5" of toe out! Completely unusable! Obviously the EMPI jigs are garbage, I should have listened to my better judgement and just used the control arms in the first place. Complete waste of time and money buying those jigs!

I am very discouraged with this project. I left it sit for the summer and moved on to other things. I will have to grind off everything I have done to this point and start over! The inner pivot point has to be moved about 1.5" rearward from where the jigs set them at.
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Our cars get old, we get old but driving an old VW never gets old!

[oprn]

[RickS]

[oprn]

This is the resulting angle.

And this is how much further back it should be to make the wheel parallel to the car.

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Our cars get old, we get old but driving an old VW never gets old!

[RickS]

[Jason37]

I used the same brand of jigs when I did mine. I test fit them to an IRS subframe (type 3) first and the fit up was spot on. Do you want me to take a measurement of mine? I’m coming north Wednesday and can drop them off if you want to borrow. It’s interesting to see the difference in pivot brackets between type 1 and 3 as well.

Here are the test fit pics

Installed pics