 Why does my 914 change track?, at any bump in even slight bends |
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| larss |
 Apr 29 2013, 06:04 AM
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#1
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Member  Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia  |
My stock 914/4 -72 handles quite well on straight roads but if I turn it into a slight bend where there is any kind of small bump it tends to loose the track, it rattles a bit in the front and comes out in a new track
The front end is all stock except for new Bilstein gas shocks (all around) and quite a bit lowered to (almost) match the rear end where it is sitting a bit. Thought this would disappear with the new absorbers but sadly it just made a small improvement. Tyres are worn 185/65's on Pedrinis 5½. No sway bars. What are the first things to check? /Lars S |
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| SUNAB914 |
Apr 29 2013, 06:10 AM
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#2
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Senior Member Group: Members Posts: 698 Joined: 29-December 08 From: Fredericksburg VA Member No.: 9,880 Region Association: South East States |
Lowered in front, need bump steer kit.
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| FourBlades |
Apr 29 2013, 06:53 AM
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#3
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From Wreck to Rockin Group: Members Posts: 2,054 Joined: 3-December 07 From: Brevard, FL Member No.: 8,414 Region Association: South East States 
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You inner and outer tie rod ends and balls joints could be worn out.
40 year old rubber bushings get wallowed out, causing the rattling. Rattling is not caused by bump steer. I have lowered my blue car until the a-arms are almost level and it does not bump steer at all. Get some (lemforder) turbo tie rods and it will totally take care of the problem. John |
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| larss |
Apr 29 2013, 07:09 AM
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#4
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
QUOTE(SUNAB914 @ Apr 29 2013, 02:10 PM)  Lowered in front, need bump steer kit. What do I have to do more than bolt the spacers in, (except for adjusting toe-in)? Is the hole for the steering shaft boot large enough to take a 10mm lift of the rack? /Lars S |
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| larss |
Apr 29 2013, 07:09 AM
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#5
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
QUOTE(FourBlades @ Apr 29 2013, 02:53 PM) You inner and outer tie rod ends and balls joints could be worn out. 40 year old rubber bushings get wallowed out, causing the rattling. Rattling is not caused by bump steer. I have lowered my blue car until the a-arms are almost level and it does not bump steer at all. Get some (lemforder) turbo tie rods and it will totally take care of the problem. John Many thanks John! Sorry I used the wrong word it does nott rattle (no noise present) but rather a quick wobble. /Lars S |
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| Krieger |
Apr 29 2013, 07:48 AM
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#6
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Advanced Member Group: Members Posts: 4,711 Joined: 24-May 04 From: Santa Rosa CA Member No.: 2,104 Region Association: None
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Check your wheel bearings to see if they are tight.
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| Mike Bellis |
Apr 29 2013, 08:00 AM
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#7
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Resident Electrician Group: Members Posts: 8,345 Joined: 22-June 09 From: Midlothian TX Member No.: 10,496 Region Association: None 
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Sounds like bump steer to me too.
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| larss |
Apr 29 2013, 08:04 AM
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#8
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
QUOTE(Krieger @ Apr 29 2013, 03:48 PM) Check your wheel bearings to see if they are tight. Thanks Krieger! I have checked the bearings, like to have a just noticeable minimal play to ensure they are not to tight. /Lars S |
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| larss |
Apr 29 2013, 08:06 AM
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#9
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
QUOTE(kg6dxn @ Apr 29 2013, 04:00 PM) Sounds like bump steer to me too. Thanks kg6dxn! What do I have to do more than bolt the spacers in under the rack, (except for adjusting toe-in)? Is the hole for the steering shaft boot large enough to take a 10mm lift of the rack? /Lars S |
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| Mike Bellis |
Apr 29 2013, 08:12 AM
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#10
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Resident Electrician Group: Members Posts: 8,345 Joined: 22-June 09 From: Midlothian TX Member No.: 10,496 Region Association: None
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QUOTE(larss @ Apr 29 2013, 07:06 AM) QUOTE(kg6dxn @ Apr 29 2013, 04:00 PM) Sounds like bump steer to me too. Thanks kg6dxn! What do I have to do more than bolt the spacers in under the rack, (except for adjusting toe-in)? Is the hole for the steering shaft boot large enough to take a 10mm lift of the rack? /Lars S Some do the spacer kit and some do turbo tie rods. The spacers are cheapest to try first. Yes the boot will be OK. |
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| larss |
Apr 29 2013, 08:17 AM
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#11
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
QUOTE(kg6dxn @ Apr 29 2013, 04:12 PM) Some do the spacer kit and some do turbo tie rods. The spacers are cheapest to try first. Yes the boot will be OK. Thanks again! Yes and if I have to fit the turbo tie rods later the spacer kit is good to keep also then (?) /Lars S |
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| rhodyguy |
Apr 29 2013, 08:23 AM
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#12
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,080 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
if you're going to have an alignment done you'll want the tie rod package and bump steer kit in place or do the alignment twice. if you have a 'pro' do it the second alignment costs will cover the tie rod and end package.
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| rick 918-S |
Apr 29 2013, 08:42 AM
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#13
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Hey nice rack! -Celette Group: Members Posts: 20,460 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region
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(IMG:style_emoticons/default/agree.gif) Bump steer kit and tie rods then alignment (IMG:style_emoticons/default/beerchug.gif)
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| r_towle |
Apr 29 2013, 09:21 AM
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#14
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Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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show a side picture of the car stance.
If the lower a-arm in front sits out of level, where the ball joint is hinger than the torsion tube....then you need to adjust the car back up just a hair. Bump steer spacer kits may not be required if you do a few things. Get the a-arms adjusted properly. Good bearings, nice and tight Good tie-rods Get some toe-in on the front end. When you just lower the car, it toes out. That makes it skittish and bump steer is drastically increased. Simple to check. Straighten the wheel so both wheels are aiming forward. Lay a block of wood on the outside of both wheels Measure from side to side from one block to the other to see if you have alot of toe out. This is crude because rubber wheels have way to much variation to be accurate, but it should give you a good idea. I also saw a trick of laying wet newspaper down on the floor in front of both wheels, then gently roll the car over the newspaper. The car (maybe) will twist the newspaper in the direction of the toe angle... So, you may not need the bump steer kit. I dont have one, never did. I had my car so low the a-arms hit the weld flange in front. I adjusted the alignment exactly to some toe-in, about 1/8 inch overall to compensate...all it well. The toe- out is what makes it feel like you are being dragged around from one rut to the next. Slight toe out is great for autox and quick turn in, but it sucks to drive around town, and it wears the inside edge of the tires out quick. rich |
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| luskesq |
Apr 29 2013, 09:32 AM
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#15
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Member Group: Members Posts: 276 Joined: 24-October 10 From: Fresno, CA Member No.: 12,303 Region Association: Central California |
First, I'd check the camber, caster, and alignment because that could affect your tracking. If okay, move on to inspecting and replacing parts suggested. If not okay, take care of that issue prior to throwing money at parts. Here is a DIY thread discussion on how to check and align: http://www.914world.com/bbs2/index.php?showtopic=202671.
Very simple. Good luck, Keith |
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| larss |
Apr 29 2013, 10:56 AM
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#16
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
Thanks everyone!
I have made several toe-in checks on different floors with my home alignment tool; Always the same result the toe in is about 3/8". The center of the A-arm is about 1½ " lower at the outer end then at the inner. The tie-rod center is about ½" lower at its outer end than at the inner. However i just checked the camber which was 0 at the right side but just under -3/8" on the left, the upper side of the rim is leaning OUTWARDS! Isn't camber supposed to be around 0 for a car like mine? /Lars S (IMG:http://www.914world.com/bbs2/uploads_offsite/www.lsmteknik.se-10787-1367254609.1.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/www.lsmteknik.se-10787-1367254611.2.jpg) |
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| Rand |
Apr 29 2013, 11:38 AM
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#17
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
I'm not buying the bump steer. It's just not that low. My car is lower than that and I don't have bump steer issues. I think something is sloppy somewhere.
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| ThePaintedMan |
Apr 29 2013, 11:47 AM
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#18
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Advanced Member Group: Members Posts: 3,886 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States
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(IMG:style_emoticons/default/agree.gif) The pictures really help. And your description of the camber does as well. You should never have positive camber (top of the tire leaning out) on just about any modern vehicle, except maybe an old tractor. Sounds like you need to get it aligned.
However, everyone's advice about replacing components still stands. Inspect everything for wear and play and before you get it aligned, replace anything that you suspect is worn out. Otherwise you'll pay to have it done twice. |
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| larss |
Apr 29 2013, 11:51 AM
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#19
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
QUOTE(ThePaintedMan @ Apr 29 2013, 07:47 PM) (IMG:style_emoticons/default/agree.gif) The pictures really help. And your description of the camber does as well. You should never have positive camber (top of the tire leaning out) on just about any modern vehicle... Thanks! About how much negative camber should I have in inches measured on a 15" rim? And also, I've made all measurements with about ½ filled fuel tank, is it supposed to be empty or full or what? Thanks again! /Lars S |
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| r_towle |
Apr 29 2013, 12:56 PM
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#20
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Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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haha,
Its not bump steer.. If anything, its to high in my opinion, but that is not your problem right now. Do you have any play in the steering wheel at rest? Any clicks when you shake it back and forth? Wear items. Bearing at steering column. U-joints under dash at steering column Rubber damper at joint under gas tank Tie rod ends, both inner and outer. Bearings LAst but not least, steering rack. I replaced everything on the list with new parts. It was the ring and pinion in the rack. I rebuilt the rack and all is well. rich |
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