rack and pinion on 02
 

I'm putting 944 brakes/suspension on my '73 1302. I'm going to use the porsche spindles with adapter ball joints. can the rack from my donor 944 be used? if not the posche rack is there a simpler method? does anyone have any pictures /diagrams of a late model 03 with factory R & P that i can compare. any info would be greatly appreciated!!

thanks!

great forum!!

john

do all 1303's have rack and pinion?
 

I own a 74...I thought 1302's were only made 71-72
or is 73 1302 first half and 1303 second half of 73?
Confused...Just the same...Does my '74 1303 have rack and pin or worm and roll?

This is the rack and pinion on my '75 model 1303 with the addition of a Gerd Weiser steering damper (as it is not originally present on these models):

http://www.keversite.nl/fotoalbum/fo...2005101803.jpg

Regards,
Walter

Not clear in that pic is the extra body panels that were used to give rigidity to where the rack mounts.

Hi Wally, hope you well,

That's a nifty looking steering damper mount! I've not felt any need to add such to my '79 '03.. Why did you choose to add a damper? What do Weiser claim it does (apart from the usual over-damping the steering feedback)?

(If you don't mind me asking) :)

Matt

Hi, thanks,

Well, originally (5 years ago) I had quite some steering unstability and thought it was because of the wider track that the 944 turbo Cup spindles gave in combination with 7"x16 wheels.
That steering damper could cure it, so was advertised by Gerd Tafel (!) then..
It didn't help (of course) because the unproper (non-centered) wheel mounting that was the fault (don't ask), in comb with old bushings of the trailing arms :mad: Well, they 'looked' ok at that time; now I know better...

But, it does work coming out of corners (because of the Bilstein gas damper) and it really not heavier steering (which surprised me, since the gas damper should give some resistance).
Also, at high speeds, I need every reassuring thought to cope with the stress/exitement of hitting a pot hole and loosing the wheel and the steering damper helps there too! :laugh:

Regards,
Walter

I've heard of guys putting 914 R&P in their Super's. The 944's have power steering :( .

Excellent picture Wally.

I have a slightly off topic question - what brand swaybar are you using?

Thanks
Jeremy

Thanks Guys! Wally, do you have any pics. that show how the tie rods connect. still not sure if it's fisable to convert to rack& pinion. anyone else??

thanks!

john

John

This shot of Steve C's new project car that has been converted to R&P may help
http://www.clubvw.org.au/images/Steves_1303.1.jpg

Cheers
Jeremy

rack & pinion saga
 

Jeremy, thanks that picture does shed some light on it. I can see now that the rack from a 944 probably won't work as well due to the tie rods being so much shorter than the SB control arms - looks like it would introduce bump steer. I'm assuming that this rack is stock late model 1303.

anyone else care to join the discussion?

thanks!

john

Thanks; well, you can clearly see I don't care much for detail :o

Well, what would live be without going OT ? ;)
In the picture you see the recently installed Topline sway bar. It has also the Topline urethane caster-correction (excentric) bushings installed. The control arms also have the urethane bushings. The ones at the inner side have the extra caster giving bushings.
The difference in ride after these new bushings and sway bar was astonishing.

Regards,
Walter

Supers in the 1971-72 model years were 1302s. 1303s started with the 1973 model year. Rack and pinion started with the 1975 model year.

There were some other changes which were made mid-1973, so some 1303s share parts more commonly associated with 1302s. How this affects a rack and pinion conversion, though, I'm not sure.

Thanks Wally, the urethane bushes make an enourmous difference to the handleing of supers!

John, yes that rack I believe is a late 1303 rack fitted to an early 03 (which previously had a steering box).

A friend of mine had looked at fitting an Alfasud rack to his super. His suggestion was to fit it higher than the stock location and use a bracket to mount the central tie rods to so they remain in the same position as they would with the stock steering box, cunning :)

Actually someone has just pointed out the Ackerman angle thing- I don't know how the factory dealt with it but it could be a lot trickier than it first seems. Ackerman is where the inside wheel turns tigher than the outside wheel- this helps reduce tyre scrb etc http://www.compgoparts.com/technical/001/Ackerman.asp

CU
Jeremy

Hi

I fitted on to my old 1302.

It’s a hard job but I believe the benefits are worth it. First find a 75 1303 that has a rack fitted. Take some measurements to get an accurate idea where the rack will bolt to the chassis rails. This is important because the inner guard has some stiffening in it that weaves around the stock steering box and idler arm mounting points.

There is a cross brace that needs to be removed that runs across the base of the spare wheel well. The depression in the 1302 chassis that the rack fits into is not deep enough so you need to make this depression much deeper. I heated mine and flattened it down with a mallet. If I ever did again I would cut the section out and weld ½ circle of heavy wall tubing in there. The job on my car was made a little easier because I have no spare wheel well as it has been removed to fit a radiator. To hold the rack in place you will need to fit some captive nuts in the chassis rail, I just cut a slit in the outer side of the inner guard, fitted some captive nuts and then re-welded the slit. I have seen these mountings fitted another way, make some sturdy 90-degree brackets to bolt to the existing the stock steering box and idler arm mounting points and then the rack can bolt to these.

The 1303 steering shaft will also hit about ½ way along so the body will need a small amount of clearancing.

Steve

Thanks Steve

I hope you don't mind, that is your new project I have linked to above :)

Do you or anyone else know if the Akerman angle is an issue with the rack mounted in that location with steering arms facing forward on the spindle / steering knuckle? It isn't the ideal setup from what the current thinking is, but the factory must have realised what they were doing when they made the car.

Cheers
Jeremy

Mathematically, the Akerman angle has more to do with the width of the front track. There would be a difference, for example, if the vehicle had a 61-inch front track versus a 69-inch front track.

When it comes to driving conditions, it gets even more complicated, albeit on a more subtle level, when tire characteristics such as sidewall flex and tackiness of the tread to pavement as well as the speed of the vehicle are factored in.

I mention this because it is possible one may not want a complete adherence to the Akerman angle given the unequal stress taken on by all four tires when cornering. (I'll leave it the racers to opin on what's desireable because I just plain don't know.)

Keep in mind, the rear tires aren't piveting at all (unless someone has instituted four-wheel steering at which point, someone owes us a tech article :D ).

Even if not perfect, a r&p system allows for the compensation necessary better than a steering box can.

I would think the amount of turning radius per steering wheel turn would be of greater concern. I read on some forum the stock VW r&p system (1975-79) is not as good as the steering box (1971-74) in that regard. If true -- and I have not yet confirmed this -- this might be a stronger point of contention when converting and upgrading. (Again, I'll leave this to the racers who would know about desireability.)

Hi Jezza no worries, thats what looked like after sitting in shed for 19 years.

The guy who owned my 1303 before me spent a couple of days on his wheel alignment machine to get the rack in the correct place so that there was no bump steer.

The Ackerman problem showed up when I 1st fitted the rack, going hard on highways the inside front wheel would give a little chirp if I crossed the centre line, this was chased back to a slightly bent strut and too much caster.

Steve

I'm watching with bated breath on your new project. Your last car was quite ahead of its time :)

Too much caster? I didn't think this was possible? What amount of caster were you running in the end?

I was lead to believe that when a car was dramatically lowered you needed to make the wheel alignment more aggressive than the stock measures.

Other than that Steve, I take it you never noticed any Akerman problems?

Thanks
Jeremy

Fitting a steering rack
 

The steering rack bolts to the body and the strengthening plates which it bolts to are already there on 1303's. These double as the strengthing plates which your steering box and idler box bolt to.
The only thing you need to add is the M10 captive nuts for the rack to bolt to.
The chassis frame head needs clearancing for the rack aswell as has already been pointed out. Once this is done, it is a real bugger to get the gearshift rod in and out so if you're going to replace that flaky old gearshift rod bush.. do it beforehand!!
MG

We are assuming the r&p Bug has the same steering geometry as the steering box '03/'02? This potential difference is near negligable when compared to the difference in Ackerman geometry when using Porsche spindles...

This is my experience with a rack'n'pinion Beetle.

I'm mostly recalling from mental notes here, the distance between the track-rod end and the steering axis is much less on my 951 stub-axles than the '03 stubs they replaced. The angle is different aswell. Also remember the Porsche stub axles have a drop spindle effect. The shorter length sharpens up the steering response/reduces the ratio, less turns lock-to lock, quite noticably. Not going to happen, as the stock wheels won't be going back on. The wide/big offset wheels that now fit under the stock front wing/fender will need steering limiting to prevent tyre fouling at the rear inner sidewall. Old news. I'm not sure if 944 'rod ends have different hieght, angle and length/steering geometry than 951. Mike Ghia, You've seen both ;) Can you check for us? How is that Kab you were building? For you father wasn't it?

Limiting the steering is easy and safe on a steering box Superbug, as the mechanism is external. Unlike the 'rack which needs stop's fitting, to limit the throw of the wheels. This involves major surgery, to do it the way I did. And must be top quality. I will be doing this op again soon as I've aquired another rack as a spare. This time I'll take pics and share them. Some people argue that we do not drive on the steering limits (e.g. common, or garden rat-look Cal lookers). I believe a sorted GL car sould be able to drive at full-lock. Agree?

People in the UK remember, any evidence of welding or even heating on a steering or suspension component is an MOT failure. :)

The shift rod bush, I struggled and failed to get my shift rod out without bending it when I replaced that on my '79, they must have been flexed when first fitted :eek: When the shift rod is slid all the way to the the end of the tunnel, the bush can be changed easily.

Matt

Matt,

Kab is coming along nicely... looking very shiney in its new paint! Spend lots of time tip-toeing around it not scratching paint!

Not sure about the welding or heating of any steering component being an MOT failure. I worked for an MOT station for a while and its not one I've come across. I'll check it out with my old boss and he can dig out the book :)

We have lengthened the steering arms by about 50mm per side. With anti bump steer kits fitted so that the track rod enters the spindle from the top, the angle of the track rod is almost identical to that of the bottom arm so pretty good.

If your wheels catch on any part of the car on full lock, its an MOT failure.. I know that much and I'll be looking to sort that out. I've only just dropped the car down on its front suspension and not tried the steering on full lock so we'll see how it goes.

MG

Save yourself the bother, I'm also a VOSA/MOT tester ;)

From the MOT bible: "structural repair by welding to a steering linkage component, or signs of excessive heat having been applied"

2.2c reason for rejection d

MOT testers guide

Hmmmmm... looks like I'll be cleaning them up nicely before they go for powdercoating then :D

Cheers
MG

That's the way we do it! :D

Welding of steering columns (shafts) is also a failure in NZ and can't be "certified" by an engineer either.

I would be curious to see what you have done regarding steering limiters. I gave this some thought a while ago, but can't remember if I came to a good conclusion :cool:

Are either of you able to share with us a measurement of the positon of the rack (eg its center) to a body component?

We didn't get 1303's out this way - other than private imports- and none that I've seen are late model ones.

Thanks
Jeremy

Jeza, I'm hoping to clean up the front underside of my Bug this summer, when the 'rack is off, I'll trace a template of the innerwing box section, picking up the exact position of the captive nuts and some relative reference points. I'll get it scanned along with a scale maybe, so it can be scaled 1:1 and printed off. Then cut out by anyone who is interested.

Matt

It's been a while since I was on the forums so apologies for that.

I'm just back on with my dads 1303LS Cab and among other things, I've noticed now that the suspension is all built up and fitted, we are going to have problems with the wheels hitting suspension on full lock. It's only running 6's up front with 205/55/16s but they touch.

I think the only way around it is going to be to dismantle the rack and fit a section of tube over the rack so that it can't move as far. Obviously the tube will have to be as close as possible in diameter to the rack so as not to catch the boot. The other option would be to have some clamps machined up to go around the rack shaft, again to limit movement.

Regarding the steering track arms, we managed to find some which were the correct length so the welded ones were used only as templates.

MG

Looking again at it, I think I might be able to just remove the boot clamps, move the boot along and slot in a section of tube with a cut in it and see what we need rather than having to take the rack off.

MG

Hi Mike,

Did you read my post's about what I did?

http://www.germanlook.net/forums/sho...ht=rack+pinion