Okay, this problem has presented itself within the last week. I have a feeling I know what it is, but I want to hear some guesses before I put the car on a lift tomorrow and poke around.

When driving straight on a level pot-hole free road, the car will pull to the right a bit, then back to the left, sometimes the other way around. Left turns are somewhat precise, right turns feel like massive oversteer.

Tie rods are new 930 Lemforders, installed less than a year ago, installed new ball joints at the same time. Everything else is old stock.

Front swaybar is adjusted evenly on both sides

My guess is: steering rack is excessively worn and/or bushings may be bad. Worst case scenario: Bent tie-rod.

Throw in your ideas

whats the caster and toe-in numbers?

I'm betting on a bad rack.

Check the steering coupler

Steering coupler... No play in the coupler. With my hand on it turning the wheel left and right, from pressure on one side to the other, i feel a 'knock' on the wheel and coupler.

Caster and toe-in... I had a printout from last year, I remember toe-in being 1/16th" each side, total 1/8th". Caster... not sure...

I was going to guess loose rack bolts.

Loose nut....








Behind the wheel...

C

Have you mixed radial and bias ply tires?

Those numbers were SO LAST YEAR.
what do you got today? get a string and tape and see what went wrong.

Where do you get bias ply tires these days? I doubt this is the problem.

rear trailing arm(s) holes are ovaled out, or the rear suspension point is wobbling somehow...
It could be loose, rusted, bent etc.

Or rear wheel bearings etc.

I would suggest you put it up in the air and wiggle the rear suspension to see if anything is wrong back there...
Ask me how I know....

Rich

If this is a new phenom, then I think a bolt or bolts have come loose at the point you last had things loose.

Places to check. Are the ball joints tight to the strut. (did the retaining pin fall out). Are the ball joints tight to the a-arms?. (did one or both of the castilated nuts come loose?, I have had that happen.) Next are the new tie rods tight into the struts? Have the bolts that hold the steering rack in place come loose? (I have had that happen and the car wondered around). Has the connection between the steering shaft and the steering rack come loose (there are two u-joints involved). Are the front wheel bearings properly snug?

I agree with John. I'd bet my money that the rack is loose where it bolts to the front axle. Did you recently install spacers between the axle and the rack?

In one of those places, you will find a loose connection.

I have some OLD racks that I have taken apart. Have never found a bad one.

Okay, bit of an update for us today...

Front suspension checks out. The tie rods, ball joints, wheel bearings and swaybar-connections are all nice and tight. Tie rods are not bent. I tightened up the wheel bearings an hour ago and also on the passenger's side the droplink was pressed up against the strut, as though the bar had 'slid' from left to right. I pushed the bar back and now it's even on both sides.

With the front end in the air I turned the wheels by hand side to side repeatedly. I felt some 'grinding' at one point or another but no play when shifting left-to-right suddenly.

Rear suspension I will inspect later this afternoon. When I had new tires put on yesterday morning I asked the tire shop to inspect the rear suspension with the wheels off for any play, they said everything checked out güdentite (but I'll double check).

My only other presumption would be that the connection from the steering wheel to the rack is bad, but the coupler in the footwell area had no slop. IIRC there is a second connection right at the rack, where the column attaches. When turning the wheel I can probably go ½" in rotation before the wheels turn in the slightest amount. I'll put the front end up again tonight as well and take off the cover plate and see if my rack bolts be loose. That's another thing I didn't have time for after correcting the swaybar issue.

Worse comes to worst, I'll need a new rack or new attachment at the column to the rack. I'll have to doublecheck everything in the PET manual first though...

right rear suspension ear is breaking off.

gawd, I hope I'm wrong, but btdt....

ok, that is new information.

If you can move the wheel at all without any tire movement, you got issues.

There are two u-joints inside the car, one up under the dashboard, and the second is at the footboard.

there is also a rubber connection between that lower u-joint and the steering rack.

And then the rack itself needs to be secure.
There is also a bushing in the steering column, but that would not produce the issue you have.

Rich

deja vu, that happened to me after an autocross in '78! Similar symptons, too. We'll keep our fingers crossed that it's not that.

First thing I checked was rear suspension ears. The left side is a little ovaled out but not enough to effect anything, the right side is perfectly fine. No cracks in either nor tearing away from the body. I should add some shims to both sides which I will do tonight.

Did all this start right after you got new tires?

This started about 3 weeks ago but it was very slight. I parked the car for the last two weeks, drove it wednesday and noticed this issue has become more pronounced.

Update: I just went through the rear suspension.

Tightened/torqued rear suspension mounting bolts and added shims I've been needing to install for a few weeks. I pulled the trailing arms outboard as far as I could then tightened them up. I hope that helps a bit and I'm going to go test-drive.

I'm out of daylight, but tomorrow I will pull the front pan and start checking steering rack stuff. I acquired a good used front rack this evening, so let's hope that's not it...

Paul I see 4 bias ply tires on YOUR race car.

Okay... test drive and food run... The car's steering is a bit more precise after tightening up the rear a bit. The play is still there in the steering wheel.

I double-checked the two joints inside the cab area on the steering column -- they're both tight and no play when turning the wheel.

Looks like it's down to ... steering rack and [______] ?

This is good.

what about anti-sway bar stuff... I remember there was a thread about the mounts separating from the fender well. Does that look OK?

Alternately, could it be wheel bearing related? I had a bad bearing that presented as an alignment prob. No noise, just pull and vibration at cetain speeds. Turned out to have a seized roller that was flaking apart and effecting other rollers- I'm sure it was gonna be a catastrophic failure eventually.

Dude.

Go with your gut. 99% of the time, you're right. I promise.

If you're adding shims and pulling out the rear trailing arms, that will throw your rear alignment out of whack. Why don't you try taking it in for a good 4 wheel alignment. Especially if you're going to try chaning the rack, then an alignment will most likely be needed.

Good luck,

Is that a period or a decimal point?

Haha, very cute salmon boy

I'll probably put the new rack in it next week since it's a bit more stable again, new a-arm bushings (i have polyurethane ones) then I'll take it for the 4-wheel alignment and try to eyeball everything. The swaybar's back in its proper location horizontally to the body. I need to get some 'clamps' like they sell for the 964 aftermarket bars so my bar doesn't shift side to side anymore.

Ahhhh, don't be so quick...I've seen the problem recently...especially with racers borrowing and swapping tires all over the place....LOTS of bias boots around!

I haven't seen the car and the suggestion was offered as somthing that fits the symptoms but is not an obvious check to perform. albeit an easy one.
I fugured the 914 faithful would have covered off the obvious stuff.

Let's get an update shall we? The saga continues...

Today I got the front end up on jack stands (two pair) and the front rack disassembled. I had the tie-rods off, front suspension partly disassembled, and the rack out in about an two hours. The hang-up was on the U-Joint right at the bulkhead in the footwell area, for some wierd reason it didnt want to let go.

30 minutes later, I've got the new rack in, tie-rods attached and bolting the suspension back to the body. I'm done at 45mins into reassembly. I jump into the cab and think "Cool! I'm at the last step!" Go to attach the U-Joint to the rack and... Fuch me... It appears that the input shaft on the steering rack is shorter for 911's than 914's. About an inch shorter.

911 Carerra/Turbo PN 901 347 210 03
914 PN 914 347 210 00

So, Good news is... Well, I should remember how to take it apart and put it back together real fast. Bad news... I get to do it all over again. AND I need new steering rack boots. My old ones are shot to shit and torn in many places.

I did indeed find out what the culprit was. It was a combination of the rubber steering coupling starting to tear and the gear for the steering rack had worn. I could turn the input about 5º-10º before the rack would turn. At 20mp that wouldn't effect steering that much, but at 70-80mph it would scare the shit out of you.

Anybody want a pair of OEM rubber-bushed tie-rods?

Update! It's all back together, working nice. Car's down at the alignment shop getting a 4-point alignment done. I should be back on the road tomorrow!

Bummer about the difference in the rack dimensions.

Glad you got it back together.

Alright, get this... I get called from the alignment shop a little bit ago. Things are all dialed in and nice. One slight problem though, Alignment guy tells me my passenger's side trailing arm is bent. -2º of toe in. I tell him wierd, never smacked it on a curb or anything. He was able to correct for it adjusting rear toe on both sides.

I pick my ride up tomorrow morning and I'll have a printout of before and after.

Can't wait!

Alan, thanks again for the smog pump bits. I'll figger a way to mount it up on the new engine how I like. I'm having trouble remembering how they go on a stock engine but I'll make it work.

Thanks everyone for the input, and thanks to our friendly neighborhood SLITS for having a steering rack.