From: longg01_REMOVE_323440_THIS_@yahoo.com
Does anyone have any suggestions for alignment specs? I was
thinking -1 degree of camber, 0 degree of caster, and 1/16 toe in.
Thank you everyone who gave me help in the past with suspension or
brake questions. I now have my car running, turning, and braking.
~CHRIS
#0754
[This is message #10136 by user longg01 on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
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Alignment
by h-bot » Tue Dec 31, 2002 11:19 am
From: markrock_REMOVE_456842_THIS_@yahoo.com
Duke:
In regard to your plan (...moving the ball joints rearward on the
upper arm to try to get more positive caster. More caster in the
positive direction will increase on-center feel), Jim Bartuska asked
me two months ago whether I had swapped the upper control arms from
side to side on #0259, Ken's and my Cosworth that competes in the
Modified class. I said no, mentally trying to recall what I had
heard about this procedure as it seemed to ring a faint bell. I
still haven't recalled, and though I wrote to Jim to inquire, I have
not heard back.
I just pulled the upper control arms out of a 76 Cosworth I am
dismantling, but they remain attached to the Monza spindles. I'll
try and separate them and swap them to see what things look like,
taking some measurements along the way.
Are you familiar at all with this suggestion? Do you know if it
will work? Does anybody?
Happy New Year one and all!
Mark
[This is message #10141 by user markrock on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
Duke:
In regard to your plan (...moving the ball joints rearward on the
upper arm to try to get more positive caster. More caster in the
positive direction will increase on-center feel), Jim Bartuska asked
me two months ago whether I had swapped the upper control arms from
side to side on #0259, Ken's and my Cosworth that competes in the
Modified class. I said no, mentally trying to recall what I had
heard about this procedure as it seemed to ring a faint bell. I
still haven't recalled, and though I wrote to Jim to inquire, I have
not heard back.
I just pulled the upper control arms out of a 76 Cosworth I am
dismantling, but they remain attached to the Monza spindles. I'll
try and separate them and swap them to see what things look like,
taking some measurements along the way.
Are you familiar at all with this suggestion? Do you know if it
will work? Does anybody?
Happy New Year one and all!
Mark
[This is message #10141 by user markrock on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
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Alignment
by h-bot » Tue Dec 31, 2002 11:51 am
From: doctorduke_REMOVE_254908_THIS_@yahoo.com
Yes, I swapped the upper control arms about ten years ago and reported
on this in my two part article in CVOA magazine circa 1993.
With the adjustments set to minimum caster it was about six degrees.
Needless to say on-center tracking was excellent, but the steering
effort increases substantially and there was enough kickback to damn
near break your arms. In addition, the ball joint angles appeared to
be near their limit of travel.
My suggestion is that you not waste your time with it. Six degrees is
TOO much caster. About one to two degrees would be best.
To move the ball joint back my suggestion would be to remove the ball
joints and bushings, weld up the holds, grind them smooth, anneal the
control arm to remove any residual stresses from welding (that's why
the bushings would have to be removed) then relocate the ball joint as
far rearward and inboard as possible. This should allow camber
settings in the 0 to -2 degree range with caster settings of 0 to +2.
If the bushings are in good condtion, they could be reinstalled and
reused.
Duke
[This is message #10142 by user doctorduke on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
Yes, I swapped the upper control arms about ten years ago and reported
on this in my two part article in CVOA magazine circa 1993.
With the adjustments set to minimum caster it was about six degrees.
Needless to say on-center tracking was excellent, but the steering
effort increases substantially and there was enough kickback to damn
near break your arms. In addition, the ball joint angles appeared to
be near their limit of travel.
My suggestion is that you not waste your time with it. Six degrees is
TOO much caster. About one to two degrees would be best.
To move the ball joint back my suggestion would be to remove the ball
joints and bushings, weld up the holds, grind them smooth, anneal the
control arm to remove any residual stresses from welding (that's why
the bushings would have to be removed) then relocate the ball joint as
far rearward and inboard as possible. This should allow camber
settings in the 0 to -2 degree range with caster settings of 0 to +2.
If the bushings are in good condtion, they could be reinstalled and
reused.
Duke
[This is message #10142 by user doctorduke on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
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Alignment
by h-bot » Tue Dec 31, 2002 1:33 pm
From: doctorduke_REMOVE_666949_THIS_@yahoo.com
--- In <a href="/group/cosworthvegas/post?protectID=219233066105193209050199029077192253163098100009128121188190230091025019053061151110147">cosworthvegas@yahoogroups.com</a>, longg01 <<a href="/group/cosworthvegas/post?protectID=091233212180056219138097203245129208071">no_reply@y...</a>> wrote:
> Does anyone have any suggestions for alignment specs? I was
> thinking -1 degree of camber, 0 degree of caster, and 1/16 toe in.
>
> Thank you everyone who gave me help in the past with suspension or
> brake questions. I now have my car running, turning, and braking.
> ~CHRIS
> #0754'
Sounds like you must be reading your TCT Portfolio. These are the
specs I recommend for best street performance.
The geometry of the lower control arm results in a loss of caster as
you increase camber in the negative direction. My suggestion is to
set the rear cam bolts, which control caster, to the full positive
position, which pushes the pivot point as far outboard as possible,
then set the camber at -1 degree and go back and tweak the caster cams
until you have achieved as much in the positive direction as possible,
EQUAL ON BOTH SIDES. Since the front cam bolts have a slight effect
on caster and the rear cam bolts have a slight impact on camber this
is somewhat of an iterative process, but the above approach should get
you to the best position in a minimum number of iterations.
You want some positive caster, if possible, but with -1 degree caster
you will be doing okay if you can get both sides to zero caster.
I am currently running -2 degrees camber and the most caster I could
get at the limit of adjustement, equal on both sides was -0.75
degrees. With 1/16" toe-in the steering had very poor on center feel,
so I changed the toe setting to 1/16" out and it's a little better,
but still not as firm as I would like. I'm looking into moving the
ball joints rearward on the upper arm to try to get more positive
caster. More caster in the positive direction will increase on-center
feel.
It's interesting that Chevrolet's toe recommendation changed from
toe-in to slight toe-out as a running change in '76. You can see this
in the change record of the AIM sheet. I've never figured out why
they changed the toe spec so many times, but it might have had
something to do with the adoption of radial tires. Radials prefer
smaller toe settings than bias or bias belted tires. I believe that
in 1975 the Cosworth was the only model offered with radial tires, but
more radial options were offered in '76. I'm suprised that they
didn't have different toe specs for bias and radial tires, but
apparently they compromised on one toe spec, regardless of the type of
installed tire.
I do all my own alignment using an inclinometer and carpenter's tape.
It's time consuming, but I end up with what I want, and I don't have
to deal with the dimbulbs at alignment shops who have little, if any,
understanding of suspension geometry.
Duke
[This is message #10137 by user doctorduke on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
--- In <a href="/group/cosworthvegas/post?protectID=219233066105193209050199029077192253163098100009128121188190230091025019053061151110147">cosworthvegas@yahoogroups.com</a>, longg01 <<a href="/group/cosworthvegas/post?protectID=091233212180056219138097203245129208071">no_reply@y...</a>> wrote:
> Does anyone have any suggestions for alignment specs? I was
> thinking -1 degree of camber, 0 degree of caster, and 1/16 toe in.
>
> Thank you everyone who gave me help in the past with suspension or
> brake questions. I now have my car running, turning, and braking.
> ~CHRIS
> #0754'
Sounds like you must be reading your TCT Portfolio. These are the
specs I recommend for best street performance.
The geometry of the lower control arm results in a loss of caster as
you increase camber in the negative direction. My suggestion is to
set the rear cam bolts, which control caster, to the full positive
position, which pushes the pivot point as far outboard as possible,
then set the camber at -1 degree and go back and tweak the caster cams
until you have achieved as much in the positive direction as possible,
EQUAL ON BOTH SIDES. Since the front cam bolts have a slight effect
on caster and the rear cam bolts have a slight impact on camber this
is somewhat of an iterative process, but the above approach should get
you to the best position in a minimum number of iterations.
You want some positive caster, if possible, but with -1 degree caster
you will be doing okay if you can get both sides to zero caster.
I am currently running -2 degrees camber and the most caster I could
get at the limit of adjustement, equal on both sides was -0.75
degrees. With 1/16" toe-in the steering had very poor on center feel,
so I changed the toe setting to 1/16" out and it's a little better,
but still not as firm as I would like. I'm looking into moving the
ball joints rearward on the upper arm to try to get more positive
caster. More caster in the positive direction will increase on-center
feel.
It's interesting that Chevrolet's toe recommendation changed from
toe-in to slight toe-out as a running change in '76. You can see this
in the change record of the AIM sheet. I've never figured out why
they changed the toe spec so many times, but it might have had
something to do with the adoption of radial tires. Radials prefer
smaller toe settings than bias or bias belted tires. I believe that
in 1975 the Cosworth was the only model offered with radial tires, but
more radial options were offered in '76. I'm suprised that they
didn't have different toe specs for bias and radial tires, but
apparently they compromised on one toe spec, regardless of the type of
installed tire.
I do all my own alignment using an inclinometer and carpenter's tape.
It's time consuming, but I end up with what I want, and I don't have
to deal with the dimbulbs at alignment shops who have little, if any,
understanding of suspension geometry.
Duke
[This is message #10137 by user doctorduke on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
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- Location: cyberspace
Alignment
by h-bot » Wed Jan 01, 2003 4:53 am
From: markrock_REMOVE_218003_THIS_@yahoo.com
Duke
Thanks. That does jog my memory, especially the mention of the
kickback you experienced.
What kind of temperature and time and procedure would you recommend
for annealing re-worked upper control arms? Is this something that
can be done in the oven of a kitchen stove? I can do the welding
and grinding part, but I'm not sure if I can do the annealing part.
I can put Barb's kitchen oven on self clean and get in excess of 500
degrees F, and maybe as much as 750 F, but instinctively I suspect
that this will not be sufficient. (I also instinctively suspect
I'll get questioned about why, after all these years, I'm so
interested in cleaning the oven!)
Mark
[This is message #10148 by user markrock on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
Duke
Thanks. That does jog my memory, especially the mention of the
kickback you experienced.
What kind of temperature and time and procedure would you recommend
for annealing re-worked upper control arms? Is this something that
can be done in the oven of a kitchen stove? I can do the welding
and grinding part, but I'm not sure if I can do the annealing part.
I can put Barb's kitchen oven on self clean and get in excess of 500
degrees F, and maybe as much as 750 F, but instinctively I suspect
that this will not be sufficient. (I also instinctively suspect
I'll get questioned about why, after all these years, I'm so
interested in cleaning the oven!)
Mark
[This is message #10148 by user markrock on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
- h-bot
- Posts: 53214
- Joined: Fri Dec 15, 2006 8:30 am
- Location: cyberspace
Alignment
by h-bot » Wed Jan 01, 2003 6:39 am
From: doctorduke_REMOVE_251165_THIS_@yahoo.com
Off the top of my head I can't remember the annealing temperature for
carbon steel, but I don't think a home oven will do it. Contact Neal
Williams. He annealed my oil pan baffle after he reinforced the weld
nuts for the V-bracket in an annealing oven where he works.
Duke
[This is message #10150 by user doctorduke on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
Off the top of my head I can't remember the annealing temperature for
carbon steel, but I don't think a home oven will do it. Contact Neal
Williams. He annealed my oil pan baffle after he reinforced the weld
nuts for the V-bracket in an annealing oven where he works.
Duke
[This is message #10150 by user doctorduke on Yahoo! Group Cosworth Vegas: http://groups.yahoo.com/group/cosworthvegas ]
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