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Posted by: SirAndy Feb 6 2004, 03:13 AM

ok, sooooo, on my way back from Jeffs tonight,
there is this off-ramp (45mph limit) with all new asphalt and nice and all and i decided to push it a bit.

i was going through at a bit over 100mph and the car was sticking well and all, no under- or oversteer, no sliding,

BUT

the front suspension felt somehow wooble-y.
i sort of had to do this (not that extreme mind you)
as the car was slightly rocking.
weirdly enough it didn't feel unsafe as the tires were sticking.

what is that?

could it be the sidewalls flexing? i'm running 225/50x15 on 7" rims.
shocks toast? (did the push down test which they passed).

comments are apprechiated,
Andy

Posted by: Racer Chris Feb 6 2004, 06:20 AM

Make sure the nut (threaded collar) that holds the shock in the strut is tight. Check all the nuts & bolts holding the suspension to make sure something hasn't come loose.

Posted by: James Adams Feb 6 2004, 07:36 AM

Push down test only works on '72 Buicks. You can have completely toasted shocks and pass the push down test on Porsches (my experience anyway).

Posted by: Jeroen Feb 6 2004, 08:33 AM

Hey Andy,

Can you try to describe it a little better?

Bumpsteer maybe?

How are your susp.bushings?

cheers,

Jeroen

Posted by: rhodyguy Feb 6 2004, 08:44 AM

perhaps you simply reached the limits of your setup. maybe 90 mph is a prudent rate of speed in that section.

kevin

Posted by: r_towle Feb 6 2004, 08:45 AM

Hey J...
Could be the adjuster on the rear of the torsion bar is a little loose fitting

Posted by: Don Wohlfarth Feb 6 2004, 09:36 AM

Andy, don't see how it could be your tires. 225's on 7" rim should give you a pretty straight sidewall and you'r got 50 series tires.
Make sure all the suspension bolts are tight. Check for worn rubber bushings.
Could be that Kevin's right, taking a 45mph ramp at 100+ could make a GT3 feel a little strange.

Posted by: Jeroen Feb 6 2004, 09:53 AM

Nah... if that was the case, he'd hear a clunking noise

cheers,

Jeroen

Posted by: ! Feb 6 2004, 10:04 AM

What is your ride height? 914s don't like to be too low.....

Posted by: F4i Feb 6 2004, 10:05 AM

I have had this on a different car it turned out to be tie rod ends.

Posted by: Mueller Feb 6 2004, 11:33 AM

just guessing here:

too fast, cold ground, cold tires (not evenly heated due to alignment/corner balance or lack of), oil on new asphalt.........take it easy, that car of yours is too damn nice to go getting up close and personal with the guard rails

Posted by: SirAndy Feb 6 2004, 02:46 PM

the whole car is slightly rocking left/right like a baby-crib ...

like you're sitting in it and someone is rocking the car by pushing on one side of the roof.

hard to describe, i guess ... <_<
Andy

Posted by: SirAndy Feb 6 2004, 02:47 PM

hmmm, that could be it. still have the original 911 tie-rods (not turbo) and original rubber bushings.

they might be toast ...

but, would that result in the described behavior ???
Andy

Posted by: fiid Feb 6 2004, 02:55 PM

I have felt the senastion you describe, but not in a 914....

Could it be that your front suspension just isn't super tight - so your shocks are a little soft, and you only have 19mm torsion bars right?? WHat do you have for a sway bar? What springs do you have in the rear?

For street tires, I think you might just be pushing the limits - I usually consider it safe to do double the posted limit for any given bend (bends only) - if you toook that thing at a real 100 - you were probably doing pretty well to make it....?

Did you tap the brakes to plant the nose before the turn?

Posted by: SirAndy Feb 6 2004, 03:05 PM

it's not a very tight turn, more of a nice loooooong sweeper,

for those who know the area, i took hwy 13 towards berkeley and merged onto 24 towards oakland.

it's the offramp (to the left) off 13 onto 24. nice new asphalt, so no bumps on the road ....

no, i did not tap the brakes, came downhill at about 110 mph, lifted throttle for a brief second, then into the turn with steady gas @ about 100 mph, went through like on rails, just the rocking was a bit irretating (sp?) ....

i don't know the torsion bar size, stock 911 '86 carrera frontend.
stock 911 black (boge?) shocks, 22mm swaybar on fairly soft (about 1" in from the front), 180lbs progressive springs in the rear.

i wasn't accelerating through the corner, just holding it steady ...
the car was NOT sliding, tires stuck like glue ...

Andy

Posted by: fiid Feb 6 2004, 07:50 PM

Have you taken it at that speed in a different car?? Is it really smooth - or is it just smooth at 60?

Was it windy?

I'm clutching at straws now....

Posted by: Gint Feb 6 2004, 10:28 PM

Like Fiid said, it could have been as simple as wind at that speed. Or some undulations in the pavement that you couldn't quite see.

Posted by: SirAndy Feb 6 2004, 11:57 PM

no wind. i would have felt any uneven spots in the road in the steering.
nada, just the car rocking

i suspect either worn bushings or something loose in the suspension,
like the tie-rod ends or something.

guess it's time for a suspension weekend,
Andy

Posted by: Jeroen Feb 7 2004, 05:56 AM

If you didn't feel it through the steeringwheel, bumpsteer is out
Tie-rods too... you'd felt it on the steering wheel

I think that leaves you either bad bushings and/or bad shocks...

cheers,

Jeroen

Posted by: Brad Roberts Feb 7 2004, 11:29 AM

I think he left out the fact that the chassis is cracked at the front control arm mounts. I'm almost 100%+ that the car needs front shocks.

Oh.. James.. the bounce test works on stock 914's (just not as well as a Buick)


B

Posted by: Jeroen Feb 7 2004, 11:36 AM

Posted by: Brad Roberts Feb 7 2004, 11:38 AM

He also installed a nice used set of Bilsteins on the rear.. combine this with worn Carrera shocks and you *might* get a funny feeling...

Hey Jeroen!! (good to see you) The early 911 site you did for Hayden is awesome.


b

Posted by: SirAndy Feb 7 2004, 08:08 PM

so, what are you trying to tell me? that the chassis is flexing?

i checked the crack, it hasnt't widened or anything.

FYI for everybody, there is a crack about 1" long close to the pass. side fron't a-arm mount. i believe it's from when the car was hit in the front. has been there ever since i owned the car.

Andy

Posted by: Andyrew Feb 7 2004, 08:24 PM

Why didnt you weld the crack? or reinforce it???

Dont have a clue about suspension (trying to figure mine out right now.. I think I need 140lb springs.)

andrew

Posted by: SirAndy Feb 7 2004, 08:45 PM

because it don't have a jig and i didn't want to weld it up without being sure the chassis wasn't bent.
after all, this IS near a suspension pickup point.

and the suspension did align OK after we dropped in the 911 front end!

as soon as i can get it on a jig and make sure everything is where it needs to be, it'll be welded up.

but my point is, if the chassis was flexing there right now, one would expect the crack to widen with all the stress i have put on the car lately.
and it didn't.
i "think" the crack happend when the car was hit (cause it's right where it was hit).

am i making sense here?
Andy

Posted by: SirAndy Feb 7 2004, 08:46 PM

so, back to the topic:

Why is my car "wobbeling" during high speed cornering?

anyone?

Posted by: Brad Roberts Feb 7 2004, 10:51 PM

Too many variables Andy. You will have to make the car do it while I ride with you. It could be multiple things.


B

Posted by: redshift Feb 7 2004, 10:53 PM

Is Andy on your fucking road_race_team?

You just told the German to go faster, and you tell me to damn near stop... conspiracy..


M

Posted by: Eric_Shea Feb 7 2004, 11:12 PM

Pre 74 struts can get "wallowed out" at the hole in the base where the ball joint connects causing erratic behavior going into and coming out of a turn. Solution = new style joints and pins.

Not sure if that's your problem but it is another area to check when eliminating causes.

Posted by: Aaron Cox Feb 7 2004, 11:13 PM

are you talking about the notched pin style ball joint?

Posted by: Brad Roberts Feb 7 2004, 11:14 PM

He has late 84 up Carrera struts.


B

Posted by: Aaron Cox Feb 7 2004, 11:16 PM

not enough spring rate? 19mm bars are stock on carrera's too right?

Posted by: ! Feb 7 2004, 11:17 PM

It's political....your car can't decide if it wants to be a left wing liberal or a right wing nazi.....

If it only pulls to the left it could also have Nascar Disease.....

If it only pulls to the right, you're a member of the NRA.....

Posted by: Brad Roberts Feb 7 2004, 11:17 PM

The car is well balanced with his current setup. I'm betting it has a bad shock or single bad tie rod end.


B

Posted by: Eric_Shea Feb 7 2004, 11:24 PM

You don't think it's a left wing Liberal?

Posted by: DNHunt Feb 8 2004, 07:57 AM

I'd start by checking the lug nuts then jacking the car and check the wheels are rotating without wooble, check bearing freeplay, then check for anything loose under the car and do a systematic retorque of all suspension parts. Then move to the back and do the same thing. Seems like looking at the car would be better than asking us when we can't see anything. I know the guys can float lots of ideas but you gotta lay hands on it to heal it.

Dave

Posted by: rhodyguy Feb 8 2004, 08:10 AM

miles, he was doing 100 and i wrote 90. i NEVER exceed the speed limit

kevin

Posted by: DNHunt Feb 8 2004, 08:46 AM

Kevin

It's hard to keep up with you.

I'm not driving that fast all the way to Cali in June. If we add in orange, yellow and red cars we'll be cop magnets.

Dave

Posted by: Brad Roberts Feb 8 2004, 11:28 AM

I NEVER thought I would see Dave Hunt utilize the BS smilie...


B

Posted by: SirAndy Mar 14 2004, 04:11 PM

FIXED!
ok, it was the ball-joints ...

we (brad and i) put the car up on the lift last night and the pass. ball-joint had about 1/2" play. yuck

replaced both sides with brand new ball joints and now the car goes straight again!
took a 15mph offramp at full throttle and it felt like on rails. no wobble anymore.

now a need a good alignment and corner balance ...
Andy