NWSooner
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06-07-12 10:28 AM - Post#2234371
I have a stock front end and all the alingnment shops around here tell me they need the specs to do an alignment.
Please help?
Thanks in advonce...NWSoooner
Our God is in heaven He does whatever He pleases.
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 beejay
"8th Year" Silver Supporting Member
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06-07-12 11:07 AM - Post#2234381
In response to NWSooner
I be darn, you're still alive and kicking!!! Good to see you back on, even if you are a Sooner-Dooner.  I have looked thru my files (it's someplace), but I can't find the spec's sheets right now. Been pretty warm around Phoenix, hasn't it??? 
Bruce
'56 4-door BelAir, 350, Holley 600, Eddie intake, TKO 600, CPP P/S and A arms, Sierra Gold & Adobe Beige
2010 VW Jetta S/W, 2.5, 5-cyl,6-spd auto.
'87 Elkie, 350 with 700r4 tranny B&M floor shift
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gotta56forme
"8th Year"Silver Supporting Member
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06-07-12 12:07 PM - Post#2234393
In response to beejay
Are the alignment specs in the shop manuals?
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 Rick_L
Honored Member
Posts: 24724
Loc: Katy, Tx, USA
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06-07-12 05:23 PM - Post#2234529
In response to gotta56forme
"Are the alignment specs in the shop manuals?"
Well sure they are.
Question is, are the original specs correct for a modified car? With what mods?
There is a sticky post at trifive.com that addresses all this in some detail. And if you're allergic to going there, I posted my thoughts on this on this forum less than a month ago.
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5clint7
Forum Newbie
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06-07-12 05:35 PM - Post#2234532
In response to NWSooner
Stock
Camber + .5° +or- .5°
Caster + 1.0° +or- .5°
Toe + 1/8” – +3/16”
Spec's for modern tires, steering, and roads:
Camber: -0.5 ° to 0°
Caster: Up to +1° for manual steering, +3° to +5° for power steering
Toe-in: 1/16" to 1/8" Better for radials
Also set the caster on the passenger side +1/4° more than the driver side. This
compensates for the crown in the road.
The stock Caster and camber should be +or-. It didn't paste well.
Edited by 5clint7 on 06-07-12 05:38 PM. Reason for edit: No reason given.
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NWSooner
Very Senior Member
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06-07-12 10:39 PM - Post#2234620
In response to 5clint7
Thank you everyone, very much in fact! Even you Beejay you Longhorn Lover you....yes pretty dang warm, but you know what they say "It's a DRY heat" 
Getting the alignment done tomorrow and will drive the car for the first time in 12 years, taking the wife out to celebrate our 27 year anniversary, appropriate since she long ago nicknamed my car "The Mistress"!
NWSooner
Our God is in heaven He does whatever He pleases.
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Jim McCall McShop
"4th Year" Platinum Supporting Member
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06-10-12 10:22 AM - Post#2235430
In response to NWSooner
Camber and toe-in are the two factors that control tire wear. Radial tires have considerably more grip on the road so less toe-in is needed as too much will cause tire wear, because of the additional grip they have over biased-ply tires such as the original. For radials toe-in should be no more than 1/16th of an inch. Camber should be +3/4 on left and +1/2 on right as this will allow the car not to pull to the right from the crown of the road. Now for the caster, which is the measurement of the angle of the spindle. If the top and bottom ball joint are directly above and below each other, then that would be 0 caster. Bearing in mind there 360 degrees to a revolution, when you lean the spindle forward at the top, then you are in - caster and when you lean it back you are in + caster. Remembering my reference to a top standing vertical as it spins until it slows down and falls over. Your front wheel and tires have that same force. The more you go negative with the caster the more that force has control of the steering, and the more you go positive, or to the back with the top of the spindle the less that force affects the steering. So my answer for the caster is a minimum of + 4 if not more for the caster. Caster does not affect tire wear as camber and toe-in but controls drivability of the vehicle. Higher caster causes the steering to return to the straight position when you release the steering wheel after turning, and at higher speeds causes the car to track straight down the road when you release the steering wheel. In the 50's, 60's and 70's power steering was an option and the more you increase caster the harder it is to turn the steering wheel at slow speeds, and because of this Chevrolet recommended about +1 caster so there would not be complaints of hard steering.The last factor in all of this called king pin inclination. The upper ball joint is slightly more in to the middle of the car than the lower ball joint. If you were to draw a line from the upper ball joint through the lower to the pavement and draw another line vertically from center of the wheel, the two lines should intersect at or before ground level. As you reverse a wheel or extent its center line outward from the hub you will cause the point of intersection of the two lines to be below ground line causing excessive pressure on all of suspension, and again make the car drive poorly and your steering parts to fail prematurely. All of my cars are set at 4-6 degrees of + caster and all drive GREAT.
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 acardon
"9th Year" Silver Supporting Member
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06-10-12 11:15 AM - Post#2235450
In response to Jim McCall McShop
One more question, the alignment shops machine measures toe-in in degrees and not inches. How many degrees is 1/16"? It's a 25 1/8" tire diameter, if that matters???
Don
66 Corvair (driving)
57 2dr HT (restoring)
56 2dr HT (waiting to be restored)
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Jim McCall McShop
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06-10-12 11:23 AM - Post#2235455
In response to acardon
Don
I did alignment at our local Chevrolet Service Dept from 69-74 and only know toe in inches. I also know Nothing about the newer computer engines, so if the front end tow is measured in degrees or the engine is not carbureted I,m LOST 
Jim
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Rick_L
Honored Member
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06-10-12 04:10 PM - Post#2235527
In response to acardon
1/16" toe in is about 0.068º if the tire is 26" tall. A little less (.063º) if the tire is 28".
Note that the number I posted is for total toe in, but the angle is for one wheel. That's how I think both are typically measured.
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Rick_L
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06-10-12 04:17 PM - Post#2235532
In response to Jim McCall McShop
That's all fine but bottom line is that you shouldn't go over +1 or +1.5º caster with manual steering.
To get 3-5º for power steering means you need aftermarket upper control arms, or that you must cut the front of the bracket where the upper control arm shaft is fastened from the frame, and move the front of the bracket about 3/8" outboard from where the factory put it. Then re-weld it.
Steering axis inclination is a function of how the spindles are machined and how the control arms accomodate that. In other words you can't change it without different spindles and adjusting the length of the control arms to match.
Increasing the steering axis inclination would be a good thing because it would lessen the "scrub radius" if you had wide wheels and tires.
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Jim McCall McShop
"4th Year" Platinum Supporting Member
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06-10-12 06:18 PM - Post#2235576
In response to Rick_L
Rick
You can get 3-5 degrees of caster by changing the upper control arms, off-set upper control arm shafts, or having a frame shop adjust the front cross member for the increased caster. I have had several done at a frame shop and the cost is usually about $450. As I said above Chevrolet recommended +1-+1.5 degrees as power steering was an option then and they needed to avoid complaints of hard steering. Using a a wider wheel does not effect the scrub radius, but using a reversed wheel will increase the scrub radius and make the steering harder to turn as well as increase pressure on steering components.
http://axialracing.com/wordpress/2012/02/08/ brando...
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Rick_L
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06-10-12 06:44 PM - Post#2235590
In response to Jim McCall McShop
"I have had several done at a frame shop and the cost is usually about $450."
Got photos and measurements? I find this hard to believe.
If the offset of the wheel is changed the scrub radius increases. It's almost impossible to put a wider wheel on a 55-57 and not increase the offset from stock. Even more important, disc brake conversions move the wheels out and increase the scrub radius.
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Jim McCall McShop
"4th Year" Platinum Supporting Member
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06-10-12 07:19 PM - Post#2235605
In response to Rick_L
Rick
Of the cars that I own I have had a local frame Shop named Gordys frame and Body shop, as he states tweak the wishbone, to achieve 4 degrees positive caster on five of my cars. The two 55 Belair Hardtops, the 57 Buick, and the 68 and 69 Camaros. The Buick was the last to be done on December 28th 2010 at a cost of $485. Take a look at my website for photos.
Jim
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f.i.57chevynut
Frequent Contributor
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06-10-12 11:59 PM - Post#2235653
In response to Jim McCall McShop
I had my 57 crossmember "pulled" back in '72. I think it had been in a front-ender before I got it. The frame shop put a stand under the center of the crossmember and pulled down on the one side to get some space between the upper control arm shaft and the frame to allow shims to have alignment adjustment, as there were no shims and the alignment could not be adjusted to specs. It used to be common on 55-57's, when people used to drive their cars (before dropped spindles).
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acardon
"9th Year" Silver Supporting Member
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06-11-12 06:51 AM - Post#2235725
In response to f.i.57chevynut
It used to be common on 55-57's, when people used to drive their cars (before dropped spindles).
The front mounted engine had a lot to do with the reason the crossmember saged in the middle. Side engine mounts improves this situation a lot.
Don
66 Corvair (driving)
57 2dr HT (restoring)
56 2dr HT (waiting to be restored)
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Rick_L
Honored Member
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06-11-12 08:09 AM - Post#2235755
In response to acardon
55-57 frames and suspensions were built with about 1º maximum caster possible.
I had a 55 back in the late 60s/early 70s that had a "sagged" crossmember. You couldn't remove enough shims to get correct camber, let alone caster. I had a local shop fix this. It wasn't his first time, as he knew exactly what to do. But this was only to get back to stock. The problem with that car was only on one side. It was due to collision damage.
In fact, I think that almost all the "sagged crossmembers" are due to collision damage.
To get 3º of caster, you'd have to spread the crossmember about 3/8" on each side - 3/4" total. I don't think you can do that without buckling the crossmember. And it would take a lot of force.
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Rick_L
Honored Member
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06-11-12 08:26 AM - Post#2235760
In response to Jim McCall McShop
Mcshop, I notice that both your 55s don't have a stock frame clip. And I didn't see anything on your other cars with any detail on the mods you speak of.
????
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 6-bangertim
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06-11-12 10:07 AM - Post#2235800
In response to Rick_L
Rick, if one was to use 15x6 chrome-reverse wheels, how do you correct the scrub radius back to zero or get it closer?
Thanks, Tim
Too Poor to Restore...My Nifty 150!
Proud owner of MISS NOVEMBER - 2011 Tri-Five Calender
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2Loose
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06-11-12 11:54 AM - Post#2235826
In response to 6-bangertim
I don't think you can Tim. With more offset, the contact patch of the tire moves further outboard of the spindles pivot center of contact with the road surface (not sure if I am explaining that correctly). It's part of the mechanical geometry of the spindle/a-arms setup and really can't be "adjusted" as far as I know.
As I have been back and forth from no offset to pretty extreme offsets with my front wheels on various projects over the years, more offset does put more load on the steering system, but for me I have not encountered any mechanical problems by running more offset on my front wheels.
Steering while parking gets harder with non-power systems, but I haven't noticed much difference, maybe a little, out on the open road when running a higher scrub radius setup. My latest project is my 55 gasser, while not a "stock" front end, I have a fairly large offset on the front rims, a pretty large scrub radius, and mechanical steering, and it is an armful to turn that steering wheel when backing through the s-turns required to get it back into my garage, but out on the open road it's pretty easy to drive.
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Rick_L
Honored Member
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06-11-12 02:27 PM - Post#2235894
In response to 6-bangertim
The only way to correct it is with spindles and control arms that have a greater steering axis inclination. What that means is that there is no simple bolt on fix.
Or you can not do disc brakes or wide wheels and tires - and that's not a real choice.
A good example is a C3 Corvette which had a 7º steering axis inclination. Or a C4 which had a bit more yet. Note that these are cars that came from the factory with wide wheels and tires.
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2Loose
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06-11-12 10:38 PM - Post#2236066
In response to Rick_L
Hadn't realized that Rick, but when ya think about it, it makes sense. Push that little spot on the road from the spindles out to where the tire contact patch is and reduce the scrub radius. How cool.....
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6-bangertim
"2nd Year" Silver Supporting Member
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06-14-12 01:04 PM - Post#2237139
In response to 2Loose
Thanks Willie and Rick! So, would a shorter upper A-arm do the trick or would I also need to lengthen the lower arm as well?
I'm thinking out loud here for my B-W trib car. Discs on stock spindles, just not fond of the stock wheels up front with the dog-dish 'caps - would look MUCHO better with a reversed wheel. Tires are 195-65/15R T/A Touring. Power steering - NEVER! 
I realize that there would be some cut-n-try involved if I was to go that far, but I do have an extra set of a-arms to play with! 
- Tim
Too Poor to Restore...My Nifty 150!
Proud owner of MISS NOVEMBER - 2011 Tri-Five Calender
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Rick_L
Honored Member
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06-14-12 05:47 PM - Post#2237218
In response to 6-bangertim
"So, would a shorter upper A-arm do the trick or would I also need to lengthen the lower arm as well?"
Neither one would help unless the spindle was changed to match. Think about it. A shorter upper or longer lower by itself would ruin your camber and do nothing else.
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