Arizona Desert
New Member
My t bucket seems to be all over the road except when I get past 50 Any suggestions? Just got car. My first Rod.
STEERING
- Thread starter Arizona Desert
- Start date
old round fart
Well-Known Member
Got radials on front? I’d check front end alignment. Welcome to the world of bucketheads.
Frontend shimmy is caused by a number of things.
The combination of worn out components and or frontend alignment will cause serious problems.
First and foremost, the components that make up the steering assembly must be in good condition. These components are:
Tierod ends
Heim Joints
King Pins and bushings
Steering links
Drag link
Radius rods
Pittman arm
Steering box bushings
Hub bearings
Shackle bushings
All of these components must be in good condition. Replace any part which shows wear, or movement beyond design specifications. If in doubt, replace it.
Assuming all of your components are OK, the next step is to align the frontend. If your T Bucket has bias ply tires then you should have a maximum of 1/8" toe in. Radials should be "0" to 1/8" toe out maximum.
The final step, (and VERY important) is to balance the complete rotating assembly! Attempt to balance your tires mounted on the hubs if possible. If this option is not available to you, then balance the components separately. Your drums or rotors and tires must be accurately balanced!
Tire inflation has been a subject of controversy for a very long time. But there is a basic starting point. For spoked wheels, (motorcycle type) start at MAXIMUM inflation. Generally 45/50 lbs. For all other tires, start at 28/32 lbs. Test your T on several road surfaces especially rough roads. Inflate or deflate your tires to minimize bouncing. You will always get some bouncing, but less is better. Make sure that both front tires have EXACTLY the same air pressure.
There is a big difference between shimmy and bounce! You need to avoid shimmy at all costs! This is a self induced harmonic which will destroy your whole frontend and possibly cause a serious accident. Shimmy starts when the rotating mass (tires, wheels, hubs, and rotors or drums) harmonics go into oscillation with the steering components(links, bushings, rods, and tie rods). They "push" against each other causing a violent back & fourth motion (Shimmy). Because this motion is self induced, it progresses until something breaks, or over come by an external force (IE: hit the brakes and slow down). It is imperative that your frontend be in absolutely perfect working order.
Have you ever rolled a tire around your garage, or down a street before? If you have, then you may recall how the surface governed the direction the tire rolled. This same condition exists on your T Bucket. To overcome this, a frontend alignment is setup to create an equal force on both front wheels. This effect is called "toe in" or "toe out". This equal force tends to overcome most road surfaces, making the frontend responsive to the drivers command. However, too much of either can create a new set of problems. Tire scuffing will be the first on the list. Then there is the problem of shimmy. Toe in tends to cause shimmy more than toe out. Zero toe in/toe out will virtually eliminate shimmy however your frontend will feel "loose". In other words, your car will walk back and forth while cruising. This effect is usually manageable, but annoying. Regardless which "toe" effect you need, limit the adjustment to a maximum of 1/8" The next adjustment available to you is "CASTER". This is the tilting of your king pin bosses. This caster effect tends to make your front wheels follow the centerline of the front axle. Caster is good for helping your T track straight. You always want the caster effect to "follow" your axle. You adjust your caster by adjusting the length of the UPPER clevises on your radius rods. Typically, about 5 degrees of caster is plenty, and in some cases 2 or 3 degrees is all thats required. Have you ever pushed a shopping cart around a grocery store, and noticed sometimes the front wheels shimmy? Thats way too much caster! So go easy on your caster adjustment. Finally, there is camber... you can't change it easily because it's built into the king pin bosses. However, as your king pin bushings wear out, you induce more camber. So check your king pins & bushings occasionally for wear.
From the NTBA
The combination of worn out components and or frontend alignment will cause serious problems.
First and foremost, the components that make up the steering assembly must be in good condition. These components are:
Tierod ends
Heim Joints
King Pins and bushings
Steering links
Drag link
Radius rods
Pittman arm
Steering box bushings
Hub bearings
Shackle bushings
All of these components must be in good condition. Replace any part which shows wear, or movement beyond design specifications. If in doubt, replace it.
Assuming all of your components are OK, the next step is to align the frontend. If your T Bucket has bias ply tires then you should have a maximum of 1/8" toe in. Radials should be "0" to 1/8" toe out maximum.
The final step, (and VERY important) is to balance the complete rotating assembly! Attempt to balance your tires mounted on the hubs if possible. If this option is not available to you, then balance the components separately. Your drums or rotors and tires must be accurately balanced!
Tire inflation has been a subject of controversy for a very long time. But there is a basic starting point. For spoked wheels, (motorcycle type) start at MAXIMUM inflation. Generally 45/50 lbs. For all other tires, start at 28/32 lbs. Test your T on several road surfaces especially rough roads. Inflate or deflate your tires to minimize bouncing. You will always get some bouncing, but less is better. Make sure that both front tires have EXACTLY the same air pressure.
There is a big difference between shimmy and bounce! You need to avoid shimmy at all costs! This is a self induced harmonic which will destroy your whole frontend and possibly cause a serious accident. Shimmy starts when the rotating mass (tires, wheels, hubs, and rotors or drums) harmonics go into oscillation with the steering components(links, bushings, rods, and tie rods). They "push" against each other causing a violent back & fourth motion (Shimmy). Because this motion is self induced, it progresses until something breaks, or over come by an external force (IE: hit the brakes and slow down). It is imperative that your frontend be in absolutely perfect working order.
Have you ever rolled a tire around your garage, or down a street before? If you have, then you may recall how the surface governed the direction the tire rolled. This same condition exists on your T Bucket. To overcome this, a frontend alignment is setup to create an equal force on both front wheels. This effect is called "toe in" or "toe out". This equal force tends to overcome most road surfaces, making the frontend responsive to the drivers command. However, too much of either can create a new set of problems. Tire scuffing will be the first on the list. Then there is the problem of shimmy. Toe in tends to cause shimmy more than toe out. Zero toe in/toe out will virtually eliminate shimmy however your frontend will feel "loose". In other words, your car will walk back and forth while cruising. This effect is usually manageable, but annoying. Regardless which "toe" effect you need, limit the adjustment to a maximum of 1/8" The next adjustment available to you is "CASTER". This is the tilting of your king pin bosses. This caster effect tends to make your front wheels follow the centerline of the front axle. Caster is good for helping your T track straight. You always want the caster effect to "follow" your axle. You adjust your caster by adjusting the length of the UPPER clevises on your radius rods. Typically, about 5 degrees of caster is plenty, and in some cases 2 or 3 degrees is all thats required. Have you ever pushed a shopping cart around a grocery store, and noticed sometimes the front wheels shimmy? Thats way too much caster! So go easy on your caster adjustment. Finally, there is camber... you can't change it easily because it's built into the king pin bosses. However, as your king pin bushings wear out, you induce more camber. So check your king pins & bushings occasionally for wear.
From the NTBA
1
3472 5
Th
. St Unit # 6
* Chino, CA 91710 * Phone: 909
-
3
93
-
4005 * Fax: 909
-
627
-
1188
1
Chassis A
lignment, Dimensioning
Tire hop or shaking issues are common in a chassi
s when the front and rear end are
not
set up or dimensioned correctly.
A few different
th
ings cause this situation.
Try
to
go thru these in
close
order.
*Check all rod ends
and kingpin bushings for play caused by wear.
*Check to see if there is any play from spindle boss to spi
ndle and shim as needed.
*C
heck the preload in the bearings
*Hydraulic or gas shocks should be used on the front and rear suspension, and in good
wor
king order.
*The suspension should be movable by pushing down on the front and rear of the car, if
this moves too freely the spring rates are too low, the car will probably bottom out on
small bumps and damage suspension components. If the car is too fir
m the ride quality
will suffer along with your back and any attaching frame bracketry
*Make sure there is nothing
limiting the
suspension travel except the shocks or bump
stops.
down travel (around 2 1/2")
up travel (
no less than 3/4”)
Shock tr
avel is the normal limiting factor. This would be from standard ride he
ight.
Installing bump stops to limit bottoming
will help extend the shock life.
*Make sure
the
front end and rear end are centered
to the frame.
** These bar adjustments should be m
ade with tires on the groun
d and the cars
weight on stands. J
ack up the car under the front axle and
rear
housing until the
tires lift off the ground no more than 1".Put stands under the frame on both sides
front and rear and
let the car back down on it's
tires.
Use caution removing the
bolts as the front or rear end may be loaded, this is what you are trying to fix
.
*When adjusting bars make sure all bolts go in easy without lifting or tweaking to
assemble, this will make certain the suspension will no
t be in a bind and create a loaded
situation. For example, the radius rods when unbolted from the frame need to be off the
ground the same amount on each side, lift them slightly and measure and push down
slightly and measure this will give the most accura
te reading.
*Check measurements from the bottom of the front center perch bolt to the outside of
both
ends of rear end housing at flange.
*Pinion angle should be set to match the motor and trans angle, usually 2
-
3 degrees
yoke up.
1
3472 5
Th
. St Unit # 6
* Chino, CA 91710 * Phone: 909
-
3
93
-
4005 * Fax: 909
-
627
-
1188
2
*Repeat from bottom ce
nter of the rear end housing (use tape and mark center on
housing) to the bottoms of the front king pins.
Get these dimensions + or
-
1/16".
*Double check that the
panard bar is centering the rear end after the adjustments were
made.
*Front axle shoul
d be at 5 to 7 degrees laid back at top when car is flat on the ground
(on tires).
*Make sure tires are balanced correctly and pressures are correct
*Steering box rotation should be centered, adjust the drag link to make the tires line up
straight.
*Mak
e adjustments to the steering wheel once the car is driving straight.
*The toe adjustment
should start at 1/8" toe out..(front of tires wider then rear of tire).
This can be adjusted easily once back on the ground
and driving, using two 15/16"
wrenches.
*Road t
est at varying speeds,
hard acceleration and braking. Adjust
tie rod
one rotation
at a time until you find what the tires/car likes.(do not jack the car back up to do the toe
adjustment).
Unrelated to the suspension, but also check;
*Free play in
the brake pedal pushrod, this should have about 1/16” of movement before
depressing the master cylinder piston.
*Check that the driveshaft is into the transmission tailshaft correct. This should be
pushed all the way in and pull out about 7/8” to 1”. This
is more important if the
driveshaft is super short, make sure the rear end can go thru its full travel without
bottoming out the driveshaft yoke in the transmission.
*Make sure all hardware has lock washers, nylocks or safety wire
This is
a
two to t
hree hour
job for two people, bu
t pays off big time in
the
driv
ability of your car.
Your Hot Rod should drive just as any other
car does when set up correct. M
ost
people spend countless hours building these cars and for some reason many will not
put i
n the time to do this last step. Spring rates, shock lengths
(
and types
) and
tire
pressures are all adjustable. Put in the added time..it will be worth it in added safety and
the overall enjoyment
you will have with your car.
From CCR
3472 5
Th
. St Unit # 6
* Chino, CA 91710 * Phone: 909
-
3
93
-
4005 * Fax: 909
-
627
-
1188
1
Chassis A
lignment, Dimensioning
Tire hop or shaking issues are common in a chassi
s when the front and rear end are
not
set up or dimensioned correctly.
A few different
th
ings cause this situation.
Try
to
go thru these in
close
order.
*Check all rod ends
and kingpin bushings for play caused by wear.
*Check to see if there is any play from spindle boss to spi
ndle and shim as needed.
*C
heck the preload in the bearings
*Hydraulic or gas shocks should be used on the front and rear suspension, and in good
wor
king order.
*The suspension should be movable by pushing down on the front and rear of the car, if
this moves too freely the spring rates are too low, the car will probably bottom out on
small bumps and damage suspension components. If the car is too fir
m the ride quality
will suffer along with your back and any attaching frame bracketry
*Make sure there is nothing
limiting the
suspension travel except the shocks or bump
stops.
down travel (around 2 1/2")
up travel (
no less than 3/4”)
Shock tr
avel is the normal limiting factor. This would be from standard ride he
ight.
Installing bump stops to limit bottoming
will help extend the shock life.
*Make sure
the
front end and rear end are centered
to the frame.
** These bar adjustments should be m
ade with tires on the groun
d and the cars
weight on stands. J
ack up the car under the front axle and
rear
housing until the
tires lift off the ground no more than 1".Put stands under the frame on both sides
front and rear and
let the car back down on it's
tires.
Use caution removing the
bolts as the front or rear end may be loaded, this is what you are trying to fix
.
*When adjusting bars make sure all bolts go in easy without lifting or tweaking to
assemble, this will make certain the suspension will no
t be in a bind and create a loaded
situation. For example, the radius rods when unbolted from the frame need to be off the
ground the same amount on each side, lift them slightly and measure and push down
slightly and measure this will give the most accura
te reading.
*Check measurements from the bottom of the front center perch bolt to the outside of
both
ends of rear end housing at flange.
*Pinion angle should be set to match the motor and trans angle, usually 2
-
3 degrees
yoke up.
1
3472 5
Th
. St Unit # 6
* Chino, CA 91710 * Phone: 909
-
3
93
-
4005 * Fax: 909
-
627
-
1188
2
*Repeat from bottom ce
nter of the rear end housing (use tape and mark center on
housing) to the bottoms of the front king pins.
Get these dimensions + or
-
1/16".
*Double check that the
panard bar is centering the rear end after the adjustments were
made.
*Front axle shoul
d be at 5 to 7 degrees laid back at top when car is flat on the ground
(on tires).
*Make sure tires are balanced correctly and pressures are correct
*Steering box rotation should be centered, adjust the drag link to make the tires line up
straight.
*Mak
e adjustments to the steering wheel once the car is driving straight.
*The toe adjustment
should start at 1/8" toe out..(front of tires wider then rear of tire).
This can be adjusted easily once back on the ground
and driving, using two 15/16"
wrenches.
*Road t
est at varying speeds,
hard acceleration and braking. Adjust
tie rod
one rotation
at a time until you find what the tires/car likes.(do not jack the car back up to do the toe
adjustment).
Unrelated to the suspension, but also check;
*Free play in
the brake pedal pushrod, this should have about 1/16” of movement before
depressing the master cylinder piston.
*Check that the driveshaft is into the transmission tailshaft correct. This should be
pushed all the way in and pull out about 7/8” to 1”. This
is more important if the
driveshaft is super short, make sure the rear end can go thru its full travel without
bottoming out the driveshaft yoke in the transmission.
*Make sure all hardware has lock washers, nylocks or safety wire
This is
a
two to t
hree hour
job for two people, bu
t pays off big time in
the
driv
ability of your car.
Your Hot Rod should drive just as any other
car does when set up correct. M
ost
people spend countless hours building these cars and for some reason many will not
put i
n the time to do this last step. Spring rates, shock lengths
(
and types
) and
tire
pressures are all adjustable. Put in the added time..it will be worth it in added safety and
the overall enjoyment
you will have with your car.
From CCR
2old2fast
Active Member
The last 2 posts are akin to dropping a Sears catalog size direction sheet for installing flashlight batteries , maybe just a bit of overkill ?!?!?way too much info all at once , reminds me of " dazzling with brilliance," vs " baffling with bull shit," I'm not sure which is worse ...
This is to help those that are not like all and are mechanically inclined, like you and me, 2old2fast. All here are chasing a dream, so no bull shit happening here. JMTCW
If they can read and follow directions, anyone can do this per the instructions. No bull shit.
If they can read and follow directions, anyone can do this per the instructions. No bull shit.
2old2fast
Active Member
With all the best intentions I have to disagree , prime example being my older brother , brilliant math mind , does trig in his head , should NEVER be allowed to touch anything mechanical , I promise , regardless of the instruction received , he'll break it , think about the people you know , we all know one ..
Neshkoro
Well-Known Member
The information listed above is all great information. Just go through it step by step and check everything and when you are finished you will be happy with the results. Especially if you are having problems with wander, wheel bounce, death wobble! You spent all that time building your car, why not spend some more time to make it right and fun to drive! Some time the simplest change can make a big difference. A prime example is my new front tires. I was having a lot of wandering issues. I adjusted caster, toe-in and even camber. (Camber was a bugger. I had to make a fixture to hold my 20 ton hydraulic jack to bend the axle.) Nothing that I adjusted made a difference. The new tires was the cure. The new wheels were a bonus.
Go for it. Worst case is it makes no difference. At least you will know all of that stuff is correct.
Go for it. Worst case is it makes no difference. At least you will know all of that stuff is correct.
fletcherson
Well-Known Member
Sort of like tuning a fresh engine... take some time to dialit in.
Arizona Desert
New Member
THANK U trying to find local shop in Casa Grande or Maricopa AZ that can be trusted enough to do this worek
OK, out of curiosity I checked the Ackerman angle on my bucket, remembering that I took that factor into account when I first set it up, but have forgotten about it since. I notice that the apex of the two lines from the king pins through the tie rod ends winds up about 3 ft behind my rear axle. What ill effect can I expect from this? It seems to drive and handle fine, albeit with a rather large turning circle.
