Conference napalm::musclecars

    I couldn't find a topic on steering so I'll put this here.
         My fathers car a '71 Cutlass Convertible developed a leak in the 
    steering box right at the bottom just above the pitman arm.  Is there
    a seal there that is easily replacable or should I look around for a 
    new/rebuilt box.  any tips would be appreciated.
    
                        Dean

    
        This is a VERY simple service item and cheap to fix. Go get a
    "pitman arm seal kit" at the dealer, and borrow a pitman arm puller.
    Also borrow a 1-3/8" or 1-1/4" (two sizes for GM) socket and 3/4"
    breaker bar, and a set of snap ring pliers. Remove the arm and the snap
    ring. start the engine and turn the steering wheel lock-to-lock, the
    seals will blow out all over the ground. Get a piece of PVC pipe
    just slightly smaller than the outer diameter of the seal and tap the
    new ones into place, and re-assemble. If you can't so it yourself,
    take it to the dealer. Its a norman service item and should be fairly
    cheap to do. My last pitman arm seal kit cost under $10.00
    
    -john

    Thanks John, I will get to it this weekend and post the results.
    
                      Dean

    I picked up the seal kit yesterday for 11.50 at carquest.  There are
    two seals in the kit.  Where does the other one go, or are there two
    seals piggy backed in there?  I haven't started the job yet so this
    may be self explanatory once I start.  I should be able to at least
    start on it tonight.  BTW the kit has two washers, two seals, and a
    new snap ring not just 2 seals.
    
                         Dean

      The seals go on top of one another with a washer in between them.
    
    Rich

    Thanks I didn't get a chance to start it last night but I 
    will do it this weekend and I'll post the results
    
           Thanks again
    
             Dean

    No problems, the job went smoothly enough and no more leaks :-).
    
    
                           Dean

    
    I own a '72 Dodge Charger and a mechanic claims my stearing/gearbox
    
    is shot and I need a new one. Also, that the free-play adjustment
    
    screw is in all the way.
    
     I dont know anything about this subject and would appreciate it if
    
    someone can offer some advice.
    
     Should I purchase a rebuilt kit or just buy a rebuilt gearbox? Is
    
    there any way the gear ratios can be changed to enhance my turning
    
    capabilities? I have power steering.
    
     This box has been leaking fluid for over 3 years, now my whole front
    
    suspension needs repair.
    
     tom
    

Give the guys at GLobal West a call.  I asked about my steering box and it
would cost about $220 for them to rebuild it.  You can try the local dealer, but
I'd bet that all they'd have is seals, nothing internal if that was what is busted.

Chris

Global West Chassis Components
1423 E. Philadelphia
Ontario, CA 91761
(714)923-6176
Chassis and suspension parts

    Looking for some thoughts/opinions:
    
    	Just bought a '62 Chevy Impala that has a steering problem of
    sorts, ie. it tends to wander indiscriminately at highway speeds.  It
    has power steering with a power valve set up similar to early 'vettes
    (power valve is on the end of the center link and connects to the
    pitman arm), and '70 wagon spindles w/disk brakes.
    
    I took it to a front end shop for an estimate as this is a tight budget
    project.  The mechanic said one tie rod end and one lower ball joint
    had a little wear, which I replaced.  He also said that the caster was
    3 to 3 1/2 degrees neg. (stock specs are 1/2 deg. pos) and neg. camber
    as well (with no shims in place).  He suggested having a frame shop
    pull the front end (lower control arms I assume, as he said the lower
    ball joints are behind the uppers).
    
    My questions:
    	Does this sound like a legitimate procedure?
    	Would the whole lower control arm be pulled forward?  or just the
   	 end of the A-frame?  Can either of these be done safely?
    	Negative camber is when the top of the wheel is tipped in, I think,
    	 and if just the end of the A-frame were pulled, wouldn't the lower
    	 ball joint come forward and in, helping to reduce the neg. camber?
    	Any ideas on what could cause this condition, as the spindles look
    	 like they were an exact fit for the control arms (upper ball
    	 joints are still original-rivited) and everything else looks pretty
    	 much stock.
    	Also, the steering box has a little play, which I think can be
    	 taken up in the adjustment.  If not, what year steering boxes
    	 would fit?
    
    Any assistance would be greatly appreciated!
    
    		Thanks,
    
    				Steve

      My brother put Trans-AM spindles in his '72 GM A-body and had
    similar problems.  DO the '70 wagon spindles have a different
    spindle height than the original ones?  IF they do there is a
    lot of factors that come into play come alignment time.  In his case
    in order to get the alignment correct he had to use adjustable upper
    A-arms (very expensive).  I would not feel comfortable with anybody
    pulling on the A-arms.
    
    Rich

    
    How about the tires?  Inflation pressure/wear/width?  All these things
    will cause some degree of wander.  
    Also, check caster - more positive caster will improve directional
    stability, at the expense of heavier steering efforts.
    
    Tom

    
    I've been doing some research on steering and suspension design
    with the objective of improving the ride/handling of my `69 Cougar.  The 
    Cougar is a rear-steer chassis, meaning the steering linkage is behind
    the front axle centerline.  This seems a rather stupid way to design a
    steering system, for the simple reason that with the positive scrub
    radius of the suspension, the natural tendency of the wheels is to toe
    out.  Thus, there is considerable force placed on the steering linkage
    to hold the wheels straight:
    
        Front
    
        |---| <----- Toe out forces
    	|   |
        |   |=== Axle
        |   |\____ Tie Rod End
        |___|
         
    It seems like there would be considerable leverage acting upon the
    tie rods and linkages associated with this set-up.  As a compensating
    measure I will take steps to minimize scrub radius.
    
    However, it got me thinking.  On my mid-size GM car, the chassis is
    front steer.  Steering response is excellent, as is the stability of
    the steering (practically no wander)
    
    What other chassis are front steer?  I think i'll limit future vehicles
    to those with this design characteristic.
    
    Tom
    

Front steering scrubs the tires whenever you deviate from a straight line.

The strain imposed by this anti-Ackerman type of steering is orders of 
magnitude greater than the strain imposed in the linkage when the vehicle 
is going in a straight line.

GM puts the steering out in front t make it easier to get the engine into 
the space between the frame rails.

Watch any steering-in-front car take a corner and you'll see the tires 
scrubbing their sidewalls as they buckle under the car (on the outside of 
the turn)  The inside tire will be dragging it's inner sidewall, too.

If you happen to see this happen on a dirt road or in a dirt driveway, the 
outside wheel will actually tear up the dirt.

The steering feels "responsive" simply because you have enormous 
tendencies to oversteer in this type of arrangement.

Whether the tie rods pull the tires together to prevent toe out or push the 
tires out to prevent the same thing is really a moot point.  Toe out is 
something you live with if you want your wheels to straighten out by 
themselves when you let go of the steering wheel after making a turn.  If 
you have neutral caster, the wheels won't scrub and they won't return to 
center, either.

BTW, most new vehicles steer from the front because there's no place to put 
the rack with the engine's oil pan in the way.

KEEP THE ACKERMAN STEERING, It's safer.

Years ago, I saw an advert. for spindles that would fit 65-73? Mustangs that
improved the geometry during cornering.  The advert. claimed that the wheels
underwent a 10 degree camber change in the *wrong* direction during a corner, 
and these spindles addressed that.  To what degree they affected the camber
in the right direction, I don't know.

I haven't ever seen them sold since, but maybe I haven't been looking.  I think
roll stiffness has a lot to do with why Mustang/Cougars don't handle well - 
even with new springs, an alignment and KYBs, mine heels over like an old 
motorboat in tight corners.  Maybe it just feels like its grinding the tires to
pieces.  I think my Landcruiser corners flatter even with no sway bars, due to 
it's very stiff leaf springs and solid axles.  I figure that mediocre cornering
is part of the charm of 60s stuff; if I wanted a car that handled, I'd get a 
newer Mustang.


steve

    re-.1
    
    Steve I have a brochure at home from a place (Mustangs Plus maybe ?)
    That has a diagram for 65-66 Mustangs that involves relocating 
    the upper A arm for better steering control...the only ads I have
    seen that mention spindles are the disk brake conversions.
    
             Dean 

    
    Actually Skip, it's a rear steer chassis that has a natural tendency
    towards oversteer.  Mind you not oversteer in the traditional sense,
    but a tendency for the wheels to turn slightly more than what's asked
    for through steering inputs.  Much of this relates to deflection of the
    soft bushings, and general flex of the tie rods, drag link, idler arm,
    etc.  
    
    I'm not at all sure that front vs. rear steer has much effect on
    ackerman (which as I understand relates to the need for a sharper
    turning angle on the inside front wheel to compensate for the sharper
    radius of turn)  perhaps you could explain this point a little more.
    
    My point is that on my `69 Cougar, the front end has considerable
    positive scrub radius, defined as the distance between the tire contact
    patch center, and and the axis of the two ball joints when viewed from
    the front:
    
        ball joint axis
               /
    tire      /
    |---|    *__ upper control arm
    |   |  _/
    |   |==
    |   | *|____ lower control arm
    |_|_|/
      | /         * ball joints
      <> scrub radius
    
    positive scrub denotes when more of the tire is outboard of the ball
    joint axis.  Therefore there is more leverage acting upon the tire when
    in motion, hence a tendency towards excessive toe-out forces.  Most
    german cars use neutral/negative scrub to improve directional stability
    while minimizing steering effort.
    
    

positive/negative scrub is more a function of rim offset/spindle geometry 
than it is front or rear steer.

As for affecting the Ackerman principle, it is nearly impossible to obtain 
proper steering geometry as defined in the Ackerman principle with front 
steering.

Simply put, a line drawn from the axis of the spindle to the center of the 
rear axle should intersect the axis of the tie rod end.

In a rear-steer, this is quite easily attained.  In a front steer, the tie 
rod end must be outboard of the spindle and usually interferes with the 
wheel or brake drum.

Front steering vehicles turn the inboard wheel less than the outboard wheel
, thus producing a skidding effect on both wheels.  When this happens, the 
weight shifts to the outboard tire which suddenly rolls under the wheel and 
the inboard tire drags to follow it.  (instant oversteer)

With proper Ackerman, all four wheels inscribe concentric arcs.  With front 
steering vehicles, only the two rear tires are inscribing concentric arcs.  
The outboard front wheel's turning radius center is behind that of the rear 
wheels most of the time and the inboard front wheel's turning radius center 
is forward of the rear wheel's turning radius center.  As the cornering 
forces increase, these turning radius centers shift around and vary the 
amount of oversteer.

The lighter the front end, the more dangerous front-steering geometry 
becomes.  Just ask Jimmy Koehler about it.  He's got a wreck in his barn 
that he can show you.  It used to be a T-bucket.

    
    Well Skip, I'll have to noodle this around for a few days.
    suspension design is a topic that resists quick understanding....
    
    However, I never contended that scrub radius is a function of front or
    rear steer.  Rather that the Cougar is a rear steer chassis and also
    possesses a lot of positive scrub.  No correlation implied other than
    my opinion that it is a poor combination.
    
    Steve, about those camber correcting spindles, a lot cheaper way to
    correct a mustang tendency towards camber change is to firm up the
    lower control arm bushing to minimize bushing deflection.  Also, adding
    a helper spring to the rear leafs will help the problem as well.
    
    Tom

    
    Hi.
    I have a question about the power steering on an Ford Torino GT -70
    with non integral powersteering.
    How much play should it be between the pitmanarm and the valve body?
    The car failed safety inspection because the inspector  thougt that
     the play in the valve was to great, about 10-15 mm with engine off 
    (No pressure in the system)
    You cant feel any play in the steering wheel during normal driving.
    
    
						/Bo Hagling.