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-   -   Wheel alignment do's and dont's tips? (http://forums.pelicanparts.com/showthread.php?t=611902)

AA_Ezra 06-02-2011 11:35 AM

Wheel alignment do's and dont's tips?
 
Ok so this is what i found out while reading the workshop manual on the wheel alignment section.

Car should have a full tank of gas( maybe if only doing the back?)
Spare tire should be in the car( again only doing the back)
Correct tire pressure on all tires
I have read however on a few posts that Need to or rather is recomended weight be added to the drivers side 150lbs so that the alignment would be correct. or is that just a race shop setup?

Im about 210lbs and recently added 200lb weltmiester springs Is it really that important to have that weight there i have a weight set that i could put on the drivers side as im not sure the shop would let me sit in it that high.

And then here is a picture of the wheel alignment specs

by the way this is for my early 944 car if that makes a difference. I have always had a shimmy shake at higher speeds and i guess is a problem for the early cars, but is that shake with these factory settings? if so any settings i should tell the shop to get rid of the high speed shimmy

thanks

http://forums.pelicanparts.com/uploa...1307039714.jpg

flash968 06-02-2011 12:18 PM

the car should be weighted as its nominally driven condition - that means with the same crap you carry around normally, the same weight in the driver seat as normal, and about a half tank of fuel - this will achieve a nominal condition that will then be in the middle of every other condition

yes on tire pressures

make sure the ride height is correct at all four corners and the tires match

shimmies and shakes are not alignment related unless things are REALLY off - they are related to balance most often, and occasionally something bent or worn - really bad tire wear can do it too - bad shocks or struts can cause that bad tire wear

AA_Ezra 06-02-2011 12:45 PM

Quote:

Originally Posted by flash968 (Post 6057634)
the car should be weighted as its nominally driven condition - that means with the same crap you carry around normally, the same weight in the driver seat as normal, and about a half tank of fuel - this will achieve a nominal condition that will then be in the middle of every other condition

yes on tire pressures

make sure the ride height is correct at all four corners and the tires match

shimmies and shakes are not alignment related unless things are REALLY off - they are related to balance most often, and occasionally something bent or worn - really bad tire wear can do it too - bad shocks or struts can cause that bad tire wear

ok so then stock specs are good. 1/2 of tank of gas is a good idea never thought about that because i wont be driving around with a full tank all the time. I have a sub box that i need to put back in as i used that alot. might take it out if i cant see my car or be close enought to hear the alarm at my new job probly toss the spare and jack in there to counter it.

all four tires are the same and have some wear on the sides but are even in the middle tread. havent lowered the rear of the car as the welt springs droped my car about 1-2 inches i think.

I think i just might do the front alignment as the back tires have allways worn evenly and will take you're advice and take some weights about 200lbs worth and put it in the drivers seat.

i guess if my alignment does cause a shake i can have them adjust it for free

944 Ecology 06-02-2011 01:06 PM

The shake that persists on 83 944 cars, even with good round wheels and good round, balance tires, can be adjusted out.

1) Make the caster maximum positive, but equal on both sides.

2) 1/8 inch of toe in.

Found this in an tech article by Bruce Anderson years ago and it cleared my shimmy up (between 55 and 70 mph) immediately.

flash968 06-02-2011 03:06 PM

just to be clear, i'm not commenting on whether or not the stock specs are "good" or not - that depends on entirely too many factors - i was only commenting on what things to do for ANY alignment, whether stock, or otherwise

AA_Ezra 06-02-2011 04:09 PM

Np I just want to have my information in order before I take it to the shop, I only drive on the street but I do hit 80- 80+mph every one in a while and don't want th shimmy so good settings for that's what I'm looking for

flash968 06-02-2011 05:27 PM

again, the shimmy almost certainly won't be related to alignment - shimmies are dynamic vibrations and related to rotating mass - unless you have obvious weird tire wear, you need to be looking at the tires and wheels for your problem

also as i said before, check your struts, upper strut bearings, ball joints, yada yada - no alignment will cure bad components, and in fact would be a waste of time and money if you don't fix those things first, as you will have to go back and do the alignment again when you do

AA_Ezra 06-06-2011 01:41 PM

ok taking it in to the shop in a few min here. printed out the spec sheet for alignment and how to adjust camber and castor and writing down for them the torque specs for the related hardware. just dont know the torque for tie rod nuts but im sure they will figure it out

im wirting down a notation that 1/8th inch for to in and castor maximum positive

AA_Ezra 06-06-2011 11:27 PM

My buddy at the tire shop didn't have time to do it today so i'm doing it first thing in the morning sometime.

Found this nice little page with some recomended settings and explanations too.
Alignment of Porsche 944

John_AZ 06-07-2011 05:53 AM

Hay, thats a nice link!

I have done a couple of "home" front alignments after I changed the front struts, PS rack or control arm busings.

Pelican "Tech Info Center" (bar above ^) has an easy DIY.
Pelican Technical Article: Home Alignment

If you wanted to do a 4 wheel alignment or check yours:
Modification Notes

GL
John

alfadoc 06-07-2011 07:22 AM

I have seen this information in several places. This is from a post on Rennlist:

"Get a height adjustment and an alignment. Replace tires first (if necessary). When the car is on the alignment rack, have the mechanic check that the car is level. On many 944's the rear is raised. There is an eccentric that offers a limited range of rear height adjustment. Get as close as possible to horizontal using only the eccentric (evenly on both sides, use the bottom edge of the door opening as a guide). Unless things are really bad it is best to put off indexing the torsion bars until replacement/upgrade. For alignment specifications of a 944 family car with factory suspension I would start with (NOT WITHIN FACTORY TOLERANCES) -1 degree camber front, -1.5 rear. 0 toe all around. Set front caster at 3 degrees 45' with 17" rims, 3 degrees even for 16" or less. Find a good mechanic (ask around at club meetings) and expect to pay. This is not a $39.95 four-wheel alignment. Expect to pay for two to four hours at the going hourly rate (and occasionally a surcharge. Good high-performance alignment mechanics are relatively rare and are compensated for it.)"

Link to original post:

Learning to drive the 944

AA_Ezra 06-07-2011 08:45 AM

Quote:

Originally Posted by John_AZ (Post 6065868)
Hay, thats a nice link!

I have done a couple of "home" front alignments after I changed the front struts, PS rack or control arm busings.

Pelican "Tech Info Center" (bar above ^) has an easy DIY.
Pelican Technical Article: Home Alignment

If you wanted to do a 4 wheel alignment or check yours:
Modification Notes

GL
John

Thanks im getting there. I like the first link i will have to try that some time.

The second link i ran into while doing a search it just looked like to much work and i have only a few of the things he used to do it. but when im working and have a weekend off i will have to try it ( no $$ right now)

AA_Ezra 06-07-2011 08:49 AM

Quote:

Originally Posted by alfadoc (Post 6066024)
I have seen this information in several places. This is from a post on Rennlist:

"Get a height adjustment and an alignment. Replace tires first (if necessary). When the car is on the alignment rack, have the mechanic check that the car is level. On many 944's the rear is raised. There is an eccentric that offers a limited range of rear height adjustment. Get as close as possible to horizontal using only the eccentric (evenly on both sides, use the bottom edge of the door opening as a guide). Unless things are really bad it is best to put off indexing the torsion bars until replacement/upgrade. For alignment specifications of a 944 family car with factory suspension I would start with (NOT WITHIN FACTORY TOLERANCES) -1 degree camber front, -1.5 rear. 0 toe all around. Set front caster at 3 degrees 45' with 17" rims, 3 degrees even for 16" or less. Find a good mechanic (ask around at club meetings) and expect to pay. This is not a $39.95 four-wheel alignment. Expect to pay for two to four hours at the going hourly rate (and occasionally a surcharge. Good high-performance alignment mechanics are relatively rare and are compensated for it.)"

Link to original post:

Learning to drive the 944

Well i did put 200lbs welts on the car which lowered the front and thought i would do the back later after an alignment. But i guess i should lower the back or else my alignment will be null if i drop it later. Looks easy enough Jack up rear of car. Loosen 2 bolts and one bolt on the shocks and let the rear adjust itself and tighten things back up. seems easy enough. i'll print another diagram for the shop guys to know how to adjust the rear if it's that way off i guess.
http://forums.pelicanparts.com/porsche-924-944-968-technical-forum/452360-bring-me-down-i-need-come-down.html

Anyone have the torque for those bolts? 36 and 24mm socket seem kinda big and im thinkign tons of torque here

AA_Ezra 06-07-2011 09:16 AM

ok so i got this pulled up and the nuts on my vehicle are both 24mm so that means its a M16 bolt according to my research so im going with 180 foot pounds as it seems to be the only one on the lis

AA_Ezra 06-07-2011 09:19 AM

http://forums.pelicanparts.com/uploa...1307463529.jpg

jcommin 06-07-2011 10:51 AM

Quote:

Originally Posted by 944 Ecology (Post 6057741)
The shake that persists on 83 944 cars, even with good round wheels and good round, balance tires, can be adjusted out.

1) Make the caster maximum positive, but equal on both sides.

2) 1/8 inch of toe in.

Found this in an tech article by Bruce Anderson years ago and it cleared my shimmy up (between 55 and 70 mph) immediately.

George,

How fast do you need to go to get wheel shimmy? I typically find mine at low sppeds. At speeds over 55, it is rock solid.

AA_Ezra 06-07-2011 02:25 PM

I thinknthe shillings at highway speeds andvabove 60-80 70-80 mph. At low speed maybe the bushings are loose worn then tighten up as the force makes them stay at increased speeds?

AA_Ezra 06-09-2011 01:33 PM

Cars still at the shop :(

flash968 06-09-2011 01:46 PM

shimmies are complicated things, but they are ALWAYS as a result of something rotational not being right - it could be a bent wheel, or an out of balance tire - the problem is that often a suspension can absorb those things up to a point, but when something like a castor block is shot, it shows up

those things being worn can make the slightest thing out of whack show up as a problem like a shimmy

so, first get a good tire balance done and check the wheels for roundness and runout

then, look to the suspension bushings, particularly the castor blocks - these are well known for failing, especially if you have any leaks, as the rubber swells and fails when it gets soaked in oils

then get an alignment when everything is right - no point in going through an alignment if a bushing is shot or a wheel is bent

AA_Ezra 06-09-2011 02:02 PM

I agree 200% never got the car aligned dice I bought because I wanted to replace everything
Rebuilt the controll arms
New tie rod assemblies
Sway bar bushings
Repacked front bearings
Front struts with konis
Welt 200lb springs
Used a better set of strut to body mounts( repackrd bearings)
And having them balance all 4 tires as one of the wheels had only 1 weight so I wanted to double check


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