she squats back and shakes her nose...

[Smurfwarrior911]

After spending four whole days constantly driving my 78 911 SC, I've noticed that she likes to shake her nose while tooling along in a straight line at highway speeds. Nothing drastic, but enough to notice and require the most suttle input to keep straight. We're talking 75mph and above. Does anyone have any ideas? No chin spoiler or tail. Alignment? Thanks for the input!

[Driver8]

I would start with an alignment. But it could also be the tires. What type of tires are you running and how old are they? I don't think you are running at the speeds were a spoiler would make much of a difference.

Aaron

[vash]

alignment.

[450knotOffice]

I'd check the alignment first.

[JeremyD]

I'd check your tire pressures first - then alignment

[Gogar]

Balance your tires, then alignment. Then a triangulated strut brace, turbo tie rods. And maybe a bare-metal respray, and oh rebuild your engine with twin plugs and 9.8:1, and webcam 20/21 cam profiles and a megasquirt and then

[450knotOffice]

Originally Posted by JeremyD

I'd check your tire pressures first - then alignment

Good idea, Jeremy. Go with the simplest item first (although my feeling is that the tire pressures aren't causing this issue, but check anyway).

[jlex]

Is tire "squirm". Could there be a broken belt on those radials? Look at them closely to see if there are any bulges. I think alignment would gradually move you to one side or the other that's correctable w/ steering; the squirm you describe sounds more like a broken belt or some other weirdness going on w/ a tire.

regards,

jlex.

[antgon]

Tire balance? A chin spoiler helped my 87 but I had a wandering issue.

[Paulporsche]

If the above don't cure it try these:

Make sure the car has a slightly nose down attitude--about 1 degree when parked on level ground. Start w/ 29 psi front/34 psi rear pressures cold.

Make sure your shocks are good.

I like a little more neg camber in the fronts than the stock setting. It feels more secure to me.

I also have a front SC spoiler w/ no rear spoiler. Again, to me it feels more secure @ 75 than a 911 w/o one.

[gtc]

I developed the same feeling last year... my alignment was way off, especially in back. I think I had positive camber on the rear wheels.

[ShakinJoe]

Try a HUGE rear wing. It will lighten up the front end where you won't feel the wobble.

[jlex]

If the tires check out okay, you may want to pay attention to what Paul says regarding the nose.... when I first got my '85, I remember thinking these things aren't very stable at 65mph & above ... felt like the car was wandering. I discounted a problem w/ the steering rack & just thought that's the way the car was ... WRONG. Had it aligned due to some weird tire wear & as part of that procedure, they put the nose at the correct angle to the car. Made a huge difference! What was happening is that the air wasn't flowing over the top like it should to hold the nose down... the front was too high & therefore it was lifting the car, causing instability at higher speeds. Like Paul says: make sure the nose is down.

regards,

jlex.

[Smurfwarrior911]

Thanks for all the advise, I will try them and report back on what fixes it! Take care

[vash]

yes. curious that you say your car "squats" and then shimmeys...

ever drive a loaded down pickup truck? shimmey. i still think alignment. please let us know.

[3.2 CAB]

Don't forget to check the front wheel bearings for proper adjustment. Loose front wheel bearings can cause a similar type event. Good luck!! Tony.