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Re: Need good alignment specs
[Re: sbcjd]
#275648
04/05/09 09:36 PM
04/05/09 09:36 PM
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Joined: Dec 2007
Posts: 10,542
BROOK PARK, OH
WILD BILL
Senior Member of the Junior Dragster Club
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Senior Member of the Junior Dragster Club
Joined: Dec 2007
Posts: 10,542
BROOK PARK, OH
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Quote:
Would the above alignment specifications you stated be the same for a daily driver with radial tires and no drag strip racing?
I'll set up a daily driver for as much caster as I can get without sacrifcing camber. Camber I like to see at 0 to . 5 deg neg. no more than a 1/2 deg split between camber/caster. Toe I want at .06
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Re: Need good alignment specs
[Re: autoxcuda]
#275650
04/05/09 10:28 PM
04/05/09 10:28 PM
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Joined: Nov 2004
Posts: 9,312
SoCal
68HemiB
master
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master
Joined: Nov 2004
Posts: 9,312
SoCal
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I'm more than a little late to this particular dance, but I aligned cars for a living in a previous life. I cannot speak to alignment specifically targeted at the auto-x crowd. The specifications for Mopar alignment back then tended toward slightly positive camber, and I have not been horribly dissatisfied with 0 to maybe 1/4 degree positive camber to this day. Therefore, you will not find me among those determined for some negative camber action. What I am in favor of is as much balanced, positive caster as possible. Besides getting toe to something reasonable (no more than 1/8" total in), in my mind there is nothing more important than getting the caster really close side-to-side. Anything else is asking for a come-back due to a complaint of pulling. Offset bushings (installed to maximize positive caster, not positive camber) are some additional help in the direction of positive caster before abandoning stock UCAs in favor of tubular numbers. 
Down to just a blue car now.
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Re: Need good alignment specs
[Re: autoxcuda]
#275651
04/05/09 10:36 PM
04/05/09 10:36 PM
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Joined: Sep 2003
Posts: 1,688
Marlboro, NY, USA
Rick_Ehrenberg
top fuel
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top fuel
Joined: Sep 2003
Posts: 1,688
Marlboro, NY, USA
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I always ALWAYS run some negative camber. The $64 question: How much? There's a whole host of factors, some of which are:
> How aggressively is the car driven? (i.e., canyon and entrance-ramp carver?)
> I assume radials (otherwise you might actually want 0° camber), but the aspect ratio is important, the lower the aspect ratio, the less negative you need
> Roll stiffness
> Tire pressure
> Wheel width to tire section width
I have run as much as 2° negative and STILL worn out the outer part of the tread first. But, then, I am an animal.
For most of my street-cruiser type buddies, I recommend 0.5 to 0.75° negative.
I like lots of positve caster but not more than 2.5 to 3 deg. or so. More is better for road racing as long as there are no REALLY long high-speed straights -- excess caster makes the car pretty spooky at very high speeds. Caster is somehow hard for a lot of guys to conceptualize. Picture a line drawn between the center of the ball joints. If this line is viewed from dead-ahead of the car, you're looking at steering axis inclination (not independently adjiustable). Viewed from the side, this same line is caster.
Rick
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Re: Need good alignment specs
[Re: 68HemiB]
#275652
04/05/09 10:41 PM
04/05/09 10:41 PM
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Joined: Mar 2003
Posts: 15,478
the boonies
aarcuda
OP
I Live Here
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OP
I Live Here
Joined: Mar 2003
Posts: 15,478
the boonies
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Quote:
I'm more than a little late to this particular dance, but I aligned cars for a living in a previous life.
I cannot speak to alignment specifically targeted at the auto-x crowd.
The specifications for Mopar alignment back then tended toward slightly positive camber, and I have not been horribly dissatisfied with 0 to maybe 1/4 degree positive camber to this day. Therefore, you will not find me among those determined for some negative camber action. What I am in favor of is as much balanced, positive caster as possible. Besides getting toe to something reasonable (no more than 1/8" total in), in my mind there is nothing more important than getting the caster really close side-to-side. Anything else is asking for a come-back due to a complaint of pulling.
Offset bushings (installed to maximize positive caster, not positive camber) are some additional help in the direction of positive caster before abandoning stock UCAs in favor of tubular numbers.
as coincidence may have it, i had just checked my 70 service manual and saw they actually called for positive camber (just like you said).
but i can see how negative camber would aid in cornering.
What do you make of the toe numbers i posted? Can I just rotate the tie rod sleeves an equal amount to get it closer to 1/16" or does it need to go back on the rack?
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Re: Need good alignment specs*** UPDATE***
[Re: aarcuda]
#275655
04/06/09 07:52 PM
04/06/09 07:52 PM
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Joined: Jan 2006
Posts: 704
USA
rftroy
super stock
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super stock
Joined: Jan 2006
Posts: 704
USA
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With all these very high caster numbers, I hope you guys are talking about power steering. The original questioner didn't mention power or manual, but you sure don't want +5 deg caster with manual steering.
I set mine at 0 to +1 for manual. Above (and at) +1, you can really feel the difference and steering gets hard.
Bob
AAR 4-speed 3.91, Tor-Red;
70 440 6 pack Roadrunner 4-speed 3.54, Plum Crazy;
68 Formula S conv 383 4-speed 3.23, Electric Blue;
69 Barracuda conv Slant 6 OD4 2.94, 71 B5 Blue;
78 Lil' Red Truck, Red;
70 Challenger S/E. 505 6 pack, Passon 5-speed, 3.55, B7 Blue
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Re: Need good alignment specs*** UPDATE***
[Re: rftroy]
#275656
04/06/09 09:20 PM
04/06/09 09:20 PM
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Joined: Sep 2003
Posts: 1,688
Marlboro, NY, USA
Rick_Ehrenberg
top fuel
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top fuel
Joined: Sep 2003
Posts: 1,688
Marlboro, NY, USA
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Quote:
With all these very high caster numbers, I hope you guys are talking about power steering. The original questioner didn't mention power or manual, but you sure don't want +5 deg caster with manual steering.
...yeah, fast ratio manual and sticky tires. One of the only real forms of exercise I get (the others are even more fun) ;->
+5° caster is crazy. Part of the problem with super-high caster settings is that the vehicle tilts significantly during the caster sweep, actually distorting the camber measurement. It can be almost impossible to prevent a lead (pull) with caster set that high.
Rick
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Re: Need good alignment specs*** UPDATE***
[Re: Twostick]
#275660
04/07/09 10:58 PM
04/07/09 10:58 PM
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Joined: Nov 2004
Posts: 9,312
SoCal
68HemiB
master
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master
Joined: Nov 2004
Posts: 9,312
SoCal
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Quote:
Too much caster can cause a violent shake after hitting a big bump at speed ie railroad tracks or potholes. 5 deg might work on a tabletop smooth track but I wouldn't want it on the street.
Kevin
Respectfully, I suggest that this symptom in a car has nothing to do with aggressive caster, and everything to do with the integrity and condition of the front suspension. For high caster numbers, I suggest one look up the factory alignment specs on a 1973 era Monte Carlo. That model exhibited none of the symptoms you attribute to positive caster.
When I was lobbying for the merits of positive caster, it was in the framework of the practical numbers one can get from a stock or near-stock Mopar front end, and in a car with power steering.
In addition to the lack of wandering and return-to-center benefits of positive caster, I also see it as a mechanism to obtain beneficial camber in turns. As I have said before, I am not in the camp of negative static camber fans (because I don't throw my pigs around corners quickly very often). However, positive caster will result in a shift toward negative camber on the outboard side and toward positive camber on the inboard side in a turn. This I find to be something desirable.
Down to just a blue car now.
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Re: Need good alignment specs
[Re: Rick_Ehrenberg]
#275662
07/12/09 10:05 AM
07/12/09 10:05 AM
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Joined: Feb 2005
Posts: 28,312
Cincinnati, Ohio
Challenger 1
Too Many Posts
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Too Many Posts
Joined: Feb 2005
Posts: 28,312
Cincinnati, Ohio
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Quote:
I always ALWAYS run some negative camber. The $64 question: How much? There's a whole host of factors, some of which are:
> How aggressively is the car driven? (i.e., canyon and entrance-ramp carver?)
> I assume radials (otherwise you might actually want 0° camber), but the aspect ratio is important, the lower the aspect ratio, the less negative you need
> Roll stiffness
> Tire pressure
> Wheel width to tire section width
I have run as much as 2° negative and STILL worn out the outer part of the tread first. But, then, I am an animal.
For most of my street-cruiser type buddies, I recommend 0.5 to 0.75° negative.
I like lots of positve caster but not more than 2.5 to 3 deg. or so. More is better for road racing as long as there are no REALLY long high-speed straights -- excess caster makes the car pretty spooky at very high speeds. Caster is somehow hard for a lot of guys to conceptualize. Picture a line drawn between the center of the ball joints. If this line is viewed from dead-ahead of the car, you're looking at steering axis inclination (not independently adjiustable). Viewed from the side, this same line is caster.
Rick
Great read, thanks Rick.
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Re: Need good alignment specs*** UPDATE***
[Re: Twostick]
#275663
07/12/09 07:40 PM
07/12/09 07:40 PM
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Joined: Sep 2005
Posts: 6,516
Santa Cruz, California
Lefty
master
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master
Joined: Sep 2005
Posts: 6,516
Santa Cruz, California
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Quote:
Too much caster can cause a violent shake after hitting a big bump at speed ie railroad tracks or potholes. 5 deg might work on a tabletop smooth track but I wouldn't want it on the street.
Kevin
I've never heard of that. On 94+ Dodge 4x4 trucks it's the other way around. Not enough positive caster causes death wobble.
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Re: Need good alignment specs*** UPDATE***
[Re: HealthServices]
#275665
07/13/09 12:40 PM
07/13/09 12:40 PM
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Joined: Sep 2006
Posts: 1,161
Los Angeles, CA
JF_Moparts
super stock
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super stock
Joined: Sep 2006
Posts: 1,161
Los Angeles, CA
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This is a great thread and I hope it gets archived.
Here's a few questions:
I just took my manual steering 71 RR to an alighnment shop and they couldn't get the caster/camber settings anywhere near the factory recommended settings. Eventually they did the toe-in and didn't charge me for the effort. The suspension was rebuilt in 1991, but since then only 3000 miles have been put on the car. Could I be looking at misaligned eccentric cam mountings?
Also, with laser alignment equipment that mounts reflectors on the wheels, is there an easy way to access the eccentric cams withthe wheels on? I was in the shop, helping the guys locate and turn the cam bolts, and we had a heck of a time doing it. (Of course it didn't help that the shop doesn't get many vintage mopars and had mostly metric tools. I can forgive the first, but not the second.)
I have an appt to get my power steering 71 Sat aligned this afternoon, and I was planning on going with these specs:
Camber: -0.5
Caster: +3.0
Toe: 1/16
One more question: Does it ever make sense to have different camber settings for left and right? Such as:
Left: -0.7
Right: -0.5
Thanks.
Jim
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Re: Need good alignment specs*** UPDATE***
[Re: JF_Moparts]
#275666
07/13/09 01:03 PM
07/13/09 01:03 PM
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Joined: Feb 2005
Posts: 28,312
Cincinnati, Ohio
Challenger 1
Too Many Posts
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Too Many Posts
Joined: Feb 2005
Posts: 28,312
Cincinnati, Ohio
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I reached around the tire with it on, to access the cam bolts. I like your specs, do you have stock upper arms? If so, you might have trouble getting 3+ caster. Mostly metric tools? 
Last edited by Challenger 1; 07/13/09 01:05 PM.
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That is a great description of how front end geometry works. Wish you could align my car. 
