924Board.org

[musicalannette]

Not sure if this is the same for all 924 and 944 cars as I only have mine to look at and measure, but the front suspension is quite a mess. Please remeber my car has its steering wheel on the right side, LITERALLY!

SO be sure to check the Left Hand Drive cars have the same problem. I'm sure someone will post after a check of there LHD car to verify this is the case.

My car has never been in an accident, you can tell this by the fact the electroplating is still in place on all the inner wing panels.... erm fenders in american. Even with no accident damage the front suspaension is a bit of a mess.

You can tell somethings wrong if you take the flat of your hand and measure the distance to the side of the tyre from the top of each front arch, I found the left front tyre nearer to my hand than the right by about 3/4 to 1 inch. This is just so you can check that your car has the same problem, if it does then i reckon you can cure you bump steer problems for less than than a $1 with no need to buy expensive kits.

The fact the front wheels are not in the middle is a problem that cannot be fixed easily as moving the crossmember left or right to centre the positions of the hubs also changes the camber values.

Anyway to the cheap fix, if you assume the two chassis rails that come to the front of the car to be the datum, you need to measure the distance from the bottom of the left hand front chassis rail to the center of the bolt head on the inner pivot of the left hand track control arm(some people may call the a lower wishbone even though it is not), in case you not sure, it is on the crossmember at the bottom, it holds the suspension arm with a rubber bush in it, try to keep the tape measure as vertical as possible to get a good reading. Now measure the distance between the right hand chassis rail and the right hand inner pivot bolt head. Be sure to measure to the middle each time. I found the left hand bolt to be nearer to the chassis than the right (looking from the driving seat), thus giving a smaller distance on the left hand side between the chassis and the inner pivot than the right hand side. Once you have the difference in value (around 7mm if i remember correctly) you need to add that value between the chassis and the cossmember to make the distances the same, unfortunatly it means loosening both sides to free off the crossmember enough to get the packers between the chassis and the crossmember.

Now the pivot points are the same distance from the turret tops we are nearly there. The next bit is very important otherwise you wont get it to work well and you will get a bit of bump steer. The rack must also be aligned to the chassis rails, i.e. parrallel. check the distance from the left and right chassis rail to your steering rack, luckily or maybee someone in the porsche design department really knew what they were doing, the rack can be adjusted quite a bit in its slots, i found mine to be parrallel at the limit of its adjusment.

It is also a good idea to check you rack is centered so the rack inner pivot points as equidistant from the track rod end ball joints. Again, this can cause small amounts of bumpsteer. To do this turn full right, stick tape at the top of the wheel, turn left counting the turns and remember the value and then stick tape at the top of the wheel, take half the value you remembered and get the tape to be symetrical. If you now put tape at the top of the wheel and remove the other bits of tape, when you drive, if your rack is centered, the tape will be at the top. I suggest you check this before you start.

All you should have to do is spend a bit of money on some metal plate to shim the front crossmember. A job that can be fixed for washers!! .

Bargain!!!!

Hope this helps.

I would be interested to know if the LHD cars are the same.
Not quite as good as a Ford Capri but getting there. It really is what happens when you mix Golf(Rabbit) with Beatle.
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I KNEW white wall tyres were invented by Americans .....just not at Boeing.... to be fitted on the 737.....

[Peter_in_AU]

Wow!!

Thanks for a great first post.
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1979 924 (Gone to a better place)
1974 Lotus 7 S4 "Big Valve" Twin-cam (waiting)
1982 924 (As featured on Wikipedia)

Learn to love your multimeter and may the search be with you

[924aussie]

[!tom]

That must explain the problem I've having.

I switched from the stock 4-lug to a 5-lug from a 931. The front left wheel rubs the fender, but the right doesn't, even with -1.5 degrees of camber.
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78 924 NA
5-lug

[musicalannette]

It does, the whole suspension on mine is off to the left. the pickup points on the crossmember and the position of the strut tops kinda screws you then. I guess 944 flared arches cure this problem.
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I KNEW white wall tyres were invented by Americans .....just not at Boeing.... to be fitted on the 737.....

[musicalannette]

So from the !toms's comment it looks as if the crossmember and front suspension have similar problems in both LHD and RHD varients, I would be interested to know if this is the same for the 944 and 968.

When I go under the car next I will take a few photo's to explain more clearly and will also show you how to make and use a tracking and cambre gauge for a few bucks.

It might be a while as ite feb and not too warm here in the UK.
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I KNEW white wall tyres were invented by Americans .....just not at Boeing.... to be fitted on the 737.....

[ptheskil]

Couple of questions...

How do you know that your pivot points are equidistant from the turret mounts unless you also measure from turret mounts to underside of chassis rails?

IIRC the rack is mounted at approx 45deg so when you adjust the rack to get it parallel with the chassis you are also moving it forwards/backwards. Is that not a problem?

I will be changing my x-member when the weather improves a bit so I will take a close look at this.

Also, there is provision in the rack to centre it using a cone shaped bolt. Did you check if this centered the inner ball joints to the chassis?
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1981 931 series2 Euro spec

[musicalannette]

Seriously, if you want to check, go to your car and see if your left front is nearer to your hand than the right front. I would be interested to know as I only have my car to judge with.


Having a quick check with a Tape Measure, I found the suspension arms to be the same length, the struts to be the same length, the rack pickup points on the struts to be the same length, therfore, if you have equal camber left to right and all the angles of track control arms and rack connections look the same left to right, the turret tops are central. I could feel mild bumpsteer and it got me looking, you can see by eye the rack and track control arms have a problem, the angles don't match. You can either correct the bottom pivot distance (easy choice) or raise the steering connector (hard choice) or shim a balljoint on a wishbone(medium choice). I'm just lazy. It really makrs a mockery of calculating roll centers, having one side track control arm mount higher than the other, and having the suspension off to one side is something i doubt was intended. It's called production line screw ups. They happen, sometimes they don't sort them out, handy for second hand buyers though.

On mine when the camber is ok, the whole setup is off to the left.

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IIRC the rack is mounted at approx 45deg so when you adjust the rack to get it parallel with the chassis you are also moving it forwards/backwards. Is that not a problem?

Sorry, I don't quite understand this, is it some sort of modified rack?

I don't know what IIRC means, or understand the next bit. Hope this helps.

I can tell you there are four mounting bolts that go through the steering rack and bolt it to the crossmember, the rack has large holes which are clamped by 4 washers and the four bolts. The large holes allow the rack to be elevated or declined at one end or the other, there is no need to move the rack forward or backwards, you just need to check one end is the same distance away from the chassis rail (holding a tape measure vertically between the top of the rack and the chassis) as the other. Simply loosen the bolts, measure nip-up, recheck measurements, adjust and recheck, if alls ok then torque down the four bolts.

Now to the rack centering, I rebuilt my rack at the same time, Follow your haynes manual, it is a good idea to get both inner ball joints on the rack to there correct position, this is where me and the haynes disagreed,I actuall made both of my inner ball joints go up as much thread as the rack would allow, this reduced the lock to lock a bit now about 3.6 turns, thus also reducing the turning circle a bit, but it also reduces the toe change as the suspension goes in to compression and droop. It is more or less at 0 toe when the suspension is at rest and because the arms and rack are more or less level at rest, as the suspension arm and rack arm move away from level toe inis added. i.e. when the suspension droops or compresses the front has more toe in, as my steering arms are nw adjusted longer (inner pivots are moved in)the change is less.

Yes I did check the distance from each strut to each inner pivot or ball joint on the rack.

Another quick tip, the golf rack has steering gaitors with no clips, its well worth fitting a couple of jubilee clips to each end of the rack to stop water and dirt ingress, sorry i'm not sure what jubilee clips are called elsewhere, you will have to look up an equivalent name.
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I KNEW white wall tyres were invented by Americans .....just not at Boeing.... to be fitted on the 737.....

[musicalannette]

Just had a uick look what IIRC means!!Wiki is great!

Stupid me, The rack is mounted on the crossmember, it mounts on a vertical surface at the front of the crossmember, held secure by four bolts which pass through the rack casing horizontally from the front of the car.

To move the rack forward and backwards you would either have to file metal or add shims. I took my crossmember off by the way, there is very little weight to it, why would you change the crossmember other than the fact the bottom two suspension pickup points are different?

Moving the rack forward might get rid of the crap initial turn in the car has. I find the first turn does very little, at slow speeds through a winding road you have to move the wheel too much. It can't be combatted with a quafe rack either, i think the arms which the rack bolt to on the strut need to be 2/3 their length (They look beatle to me, as is the complete rear suspension/brakes on mine) to get nice precise steering. Moving the rack forward until the steering arms are sqare to the car might help a bit. But the rack wll be sitting on 50mm worth of shim, not ideal, shortening the steering arm on the strut would be a GOOD MOVE I think. It would make it steer like a Ford with better handling. All german cars seem to suffer from poor steering response, i think it smoething to do with Autobahns, certainly, Jags don't sufer from it.
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I KNEW white wall tyres were invented by Americans .....just not at Boeing.... to be fitted on the 737.....

[ptheskil]

IIRC (see what I did there ) the front struts are shared with the superbeetle. I can certainly vouch for the fact that the steering of my 932 shares certain characteristics with my mother's 1303. At least it's rack and pinion so we should be thankful for small mercies I guess.

When I rebuilt my rack I stuck with the specified rack length (inner ball joint to inner ball joint) to preserve the toe characteristics you mention, but I agree that a (numerically) lower steering ratio would be better - especially as the steering is pretty light when correctly adjusted.

So anyhow, on to the measurements. Did a quick check by hand and the clearance was pretty much the same on each side so had to get out the spirit level and tape measure. Result: the front end is offset 2.5mm to vehicle LHS using the edge of the front wings as a datum. I can't say I'm comfortable with that as a reference point but it'll have to do for now. I know for a fact that my crossmember is offset somewhat to the LHS in the slots but I have not checked the lower pivot points WRT the chassis so can't say if they are central or not. I always assumed that the slots in the crossmember were there for exactly the reason that it could be adjusted to centralise the suspension. If the turrets and chassis are not aligned then there's not much we can do about it without getting violent. When I get a chance I'll get under there and take a load of measurements. Until then, I'd say mine was pretty much central.

The point I was making about the rack mounting is this. On my car, which AFAIK is stock, the mounting face for the rack is at approx 45deg to vertical. The rack mounts on a triangular pressed steel bracket which is an integral part of the crossmember. On my car, if I adjust the rack height up by "x" it will move towards the rear of the car by about "x". I've got a picture somewhere which I will post when I can find it. My rack mounting is certainly not vertical. Hence my comment about moving the rack end forwards/backwards when adjusting it down/up. Also, I only have about a couple of mm adjustment in the rack position. What's going on here then?

BTW, I recently had the front end professionally set up on a laser rig (including rack centering) so I am confident that the geometry is spot on.

PS. Since I replaced the shocks and had the front end aligned I have had zero bump steer.

I hope you don't mind me having a bit of fun with my TLAs and FLAs. What would we do without Wiki!

Oh yes, I drive on the correct side of the road like you do and my car is RHD. As a result I also understand you perfectly when you mention jubilee clips.
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1981 931 series2 Euro spec

[musicalannette]

OMG!! Your from Essex!!! Let me know if you heading up to Leicester as my mates daughters won't be safe! Mind you niether will half the farm animals!!

Is it true people from Essex have webbed feet?

Only kidding.

It sounds like your racx mounts very differently from mine. Mine is a 1983 Non lux 2.0, cheap sod who ordered it never even payed for a second wing mirror. I can tell you the rack mount directly to the crossmember on it's vertical part at the front. The crossmember is made of pressed steel, there are adjustment slots where the crossmember bolts to the chassis rails on one side, however there are just holes the other side where it bolts to the chassis meaning that there is little adjustment of the crossmeber left to right without opening the holes on the crossmember into slots. As it was june when i did this, I can't remember which side is holes and which is slots. I think the rack is VW Golf (well at least new golf track rod ends fit it!).

I will take a few photos as a walk through of what I did. It worked for me, but it won't be until later in the week(weather permitting). The bump steer was bad enough that at 50mph on an undulating straight road you would notice it. If you have to let the wheel move left or right as the car goes over a crest and then go the other way as it goes into a dip when travelling in a straight line, then you have bumpsteer. Don't get me wrong, you can drive around it, but when it's sorted the car turns into a peach.(if only i could get the initial turn rate up a bit, a taller 5th gear and better seats and a supercharger and I would be completely satisfied with it). So much so i am going to LPG it and run it till the wheels fall off (which might be quite soon as I fitted new wheel bearings!!).

Perhaps your crossmember is slightly different and thus the bottom arm pickup points are both the same distance from the chassis rails, this might be of interest to others out there with a similar car, I really would like to hear from a few more others.
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I KNEW white wall tyres were invented by Americans .....just not at Boeing.... to be fitted on the 737.....

[ptheskil]

Ha ha. Right let's get a couple of things straight. WORK in Essex, LIVE in Hertfordshire, FROM Bristol. Sadly for my kids they're a couple of Essex girls though. I have never come across webbed feet in Essex but I can assure you that most of Norfolk have them. And they talk funny. Anyhow back to steering...

Clearly our x-members are very different. I am aware that the 924S/944 had different cast x-members but yours sounds different again. Maybe there is something different with the latest 924's. Hopefully somebody else will comment.

Since I stiffened up the shocks and adjusted out the toe-in the turn in is much better but still not as good as a modern Ford. It's not a bad compromise though for a near 40 year old design.

https://picasaweb.google.com/lh/photo/7r0dYwnSeoJ0H3IYp4HuddMTjNZETYmyPJy0liipFm0?feat=directlink
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1981 931 series2 Euro spec

[Harm]

[musicalannette]

Yes looking at the crossmember is VERY DIFFERENT to a standard 2.0 those two brackets that stick out from the crossmember are not there and the rack ounts to where the two bracketts are fitted on a bog standard 2.0.

I would also guess as they have gone to that trouble they have managed to drill the holes in the right place to mount the track control arm this time.

I will do some photos as soon as i get time with a walk through of what you need to do if your crossmember is not like the on pictured above.

Thanks for the photo of a 924 turbo crossmember (is that the same as a 944?).
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I KNEW white wall tyres were invented by Americans .....just not at Boeing.... to be fitted on the 737.....

[musicalannette]

Here is a quick photo showing where it is important to have the distances the same;

A = B

C = D

I found "A" and "B" where NOT the same.

[img]https://picasaweb.google.com/102302523869797900180/RecentlyUpdated#5715312533901308978[/img]

hmmm..... put in the web address and start stop "img" tags but the photo doesnt come up. not sure about this, had to open a picsa account, is there anyweay of uploading photos directly on here? if not, anyone have any ideas what i am doing wrong?
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I KNEW white wall tyres were invented by Americans .....just not at Boeing.... to be fitted on the 737.....