Rack and pinion conversion 1303 74->75

[jhu]

Hi, when I discovered serious rust in the frame head I knew the body had to come of the pan. Just welding rust is boring stuff, so I figured I would convert it to rack and pinion at the same time. My car is severely lowered and was suffering from the occasional jamming of the pitman arm in the trailing arm, not a good feeling, but a rack and pinion will cure this.
I did as much research as I could but I could not find a step by step description so I figured I could document how I did it.

I did a lot of rust welding in addition to the conversion but I will spare you those pictures.

Here is the frame head, at this point I had removed the bottom and repaired the vertical sides of the top half. I did not want to remove the locating tabs for the the trailing arms, so I cut them at an angel to gain access.

I got the frame head of a 75 from a local dealer, but when I saw it I knew I could only use pieces of it.

I cut a cardboard template of the notch in the 74 frame head to figure out how big the difference was.

Here you see the template on top of the 75 frame head... quite a big difference.

Cleaning up the 75 head for surgery.

Here is a picture of the reinforcement vw have placed inside the frame head.

Here is a measurement to make sure the body would fit back on after the conversion.

[jhu]

Same measurement on the 75 frame head

Cleaning up the 74 head, and grinding away the fat bead of weld above the mounting point.

Laying down the cut lines at the edge of where the shapes match, also taking into consideration where Iwould have access to weld from the back side.

The first cuts made, one issue, the reinforcement don't follow the outer shape to good where I choose to cut it on the 74. (75 was much tighter at this spot) I fixed this later with a couple of notches and some panel beating on the edge.

Here is the 75 piece in its new location, fits quite nicely.

To be able to fully weld the inner reinforcement I cut back the outer edges five millimeters.

Another view of the cuts and the welds needed, here it becomes apparent why the bead above the brackets had to go.

The first welds done, one have to take into consideration the shrinkage the welds introduce and try to "balance" where to weld to avoid warping the frame head.

The front part is only single skin.

First round completed.

Second round completed.

Welds ground down and new fat beads laid above brackets. If I didn't have access to the backside I would not have ground down the welds. Strength is a good thing.

Inside before welding, quite good penetration of the welds, IMHO.

The shape of the reinforcement behind the brackets also differ.

Nothing a little weld can't fix.

Part way thru welding the inside.

Floor pan converted, and bottom half welded back on, used a pattern part from Denmark, "had to" slice it in 6 pieces to get it to look like the original part. The pan then had a few hidden rust traps exposed and repaired before being painted in Por15.

Thanks for looking!

[jhu]

On to the body. I started on the driver side by fixing rust in the front divider wall... where a normal bug has five sheet metal pieces meeting in one point, I found that the super has nine! pieces. Rust fest... It all looked ok from the outside but when you get crunching sounds when you undo the two big bolts underneath you know you have some digging to do! Getting the repairs to look as close to stock as possible is a personal goal for me... no matter how hidden they are.

Here I have cut away some of the heater channel and rebuilt the inner parts of the divider wall. Like making a new "cage" for the loose nut in there.

Opening up more to place the weld in nuts

Another angle of the reinforcement for the steering box. Notice the plastic bung closing of a hole, I first thought that it might be the right place for the weld in nut, but no such luck.

Luckily I had a NOS frame rail and quarter panel for a super for another project. And that turned out to be a universal piece, with provisions for bot steering box and rack n' pinion So there is three versions, first the 73-74 (on the right side) then the 75 with only weld in nuts, and the universal (on the left side)

[jhu]

Cleaning out the reinforcements to get access to both the rust trapped between the frame rail and the outer reinforcement, and to weld in the nuts.

This is the end of the spare tire reinforcement, the 75 doesn't have this and at least the ends needs to be removed to fit the rack and pinion.

Rust repaired and the frame rail extended all the way to the heater channel. I also welded up the holes left by the steering gear, to avoid getting water in there. I also discovered rust behind the legs of the shock tower, so it was cut away and a piece fabricated.

Here is a small piece from a cut up 75... all rusted out.

This is how the 74 frame rail looks after you have removed the spare wheel well reinforcement, the holes have to go before drilling up the needed new ones.

A tricky measurement on the NOS part... measure twice

Drilling out the spot welds under the spare wheel well.

A couple of spot welds have to be drilled from the opposite side.

A pair of sandblasted 75 weld nuts welded in on the 74...

From the underside.

All closed up... with a new "leg" in place for the strut tower. At this point I had fixed the heater channel and welded in a new hookies heater channel bottom.

Here is the other side after rust removing and converting, just the closing panel left.

Closed up painted and rack and pinion mounted.

Pretty tight in there... cant quite understand how you could get it in there without notching the frame head. Maybe you save some space by removing the rubber booth, but how wise is that?

[jhu]

A better picture of the clearances.

Without the rack.

Driver side all done

The other parts you need of a 75... the longest of both types are the 75 version. (the others are 74)

Hope this gives some insight in what differs between the 74/75.

Thanks for looking

[Dubmatix]

After buying a 73 shell to replace my rusty 75 shell, i am doing this work to bring the old shell up to 75 spec. This is a very useful reference without which i might have just opted to retain the steering box that came with the earlier shell! Just got some bits of rust trapped between the panel and strengthener to sort too and then i can put the nuts in. The hybrid panel picture is great, it shows that the box mount spacer gves you the precise fore-aft location of one of the nuts which is a great reference as a double check.

Thanks for posting!

John
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[VWCOOL]

Good job, explained/shown very well

[Metamatic]

Very good job and I thank you sp much for showing and explaining everything in detail.
.
I'm currently doing a total body off restore on my 73 convertible and was thinking of a rack conversion when I have everything off. I am tempted to do it but I'm afraid I'm lacking the courage.

[Bugs'n'Pugs]

Am I correct in drawing the conclusion that having a Rack and Pinion Steering system such as those found in the 1975-1979 Super Beetle eliminates the need for a Steering Damper and Idler Arm? (I'm just a bit confused because I have seen 1971-1979 Steering Dampers and 1974-1979 Idler Arms advertised.)
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[Dubmatix]

You are correct, there are no idler arms or damper on the rack versions of the 1303. Indeed the idler arm mount and steering box mounting holes are not present on the rack fitted cars.
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The Emergency VW Group Forum

1303 RestoBlog

1303/Latebug parts for sale and '03 shell soon to be available for cuts

Wanted: 1302/3 Front Valence (VW panel new or used in good order) and 3 point seat side plastics

1x NOS Decklid Thermostat and Vent Flaps left FOR SALE