FAQ
How much driveline angle is
right for my application?
That's a loaded
question. The best answer is....the least amount of driveline or
u-joint angle is the best amount of angle. Try to achieve the least
amount of u-joint angle but don't make it less than 1 degree. A little
known fact about u-joints is that they require about 1 degree of
operating angle to get the needle bearings rotating. If they do not
rotate they will fail. Too much angle will also cause them to fail. The
type of rear suspension also plays a big part in setting the angles as
well as the engine/transmission angle. Hard acceleration as in the case
of a drag race car requires a different setting than a street driven
car. Traction bars, ladder bars, 4 links, independent rears all have
special needs and requirements.
Is driveshaft balance
really necessary?
YES! Driveshaft balance
is necessary for smooth driveline operation and to eliminate the
destructive effects that an unbalanced or poorly balanced driveshaft
will have on your transmission and rear end. All Driveshafts are High
Speed High RPM Balanced to meet or exceed the top rpm requirements of
your engine and transmission, especially in the case of an overdrive
transmission where the driveshaft rpm is greater than the engine rpm in
high gear. This is very important and should not be overlooked when
purchasing a new driveshaft. True high speed balance means balancing at
a High RPM.
DRAG RACING DRIVESHAFTS
AND STREET SHAFTS
With today’s higher
HP/Torque motors, higher RPM drive trains and sophisticated suspensions
you need to know what you’re doing to make a shaft today. We have
driveshafts manufactured in standard carbon steel, Chromoly,Carbon
fiber or 6061-T6 aluminum. All of our carbon steel and Chromoly shafts
are welded to demanding specs using unique slow feed lathe mounted
welders using a special powdered core wire that has a higher tensile
strength than conventional welding. Every shaft is balanced on state of
the art computerized two-plane balancers and weights are attached with
special rivet type mounts. All this is great. But before any shaft is
made we carefully make sure the shaft is designed to spec before having
it manufactured, we could just make a simple flyer to ask what’s needed
and we do have that for lower powered cars. We feel at a higher level
of competition cars we need to talk to you and give you a personal
assessment of the car to assure its proper part.
We will need to know the
following:
-
HP/Torque of the motor
-
Transmission
-
Rear ratio
-
Rear tire size and height
-
Top MPH the car will see
-
Weight of the car with driver
With this info we will
be able to check for overall strength, critical speed and durability
needed. All shafts are hand made and carefully packed for shipping. If
you’re looking for a racing shaft give is a call and let us make you a
custom shaft for your application.
To check for critical
speed, calculate this equation:
Top speed x 336 (a
constant) x rear ratio (like 4.10), then divide it by the tire height
(28” tall tire).
Here is an example:
Top speed is 160mph x
336 = 53760 x rear ratio of 4.10 = 220416, then divide this number by
the tire height, 28”. This car would have top RPM of 7872. Now the
shaft being designed will need to be able to so this RPM.
STREET ROD DRIVESHAFTS
We have shafts
manufactured from simple carbon steel to Chromoly and finish up the
line up with 6061-T6 aluminum. These shafts can be made in any style or
arrangement. Where we differ from most companies is that we have an
understanding of the entire car.
DRIVESHAFT VIBRATION:
101 (not for CV axles)
Most people have trouble
determining if the vibration in their vehicle is coming from the
DRIVESHAFT or not. There are typically two types of vibration most
vehicles would have. A fast cycle vibration or a slow cycle vibration,
to help understand this lets say we put a bucket of water on the
passenger’s floor. If the vibration in the vehicle produces small
ripples on the top of the water this would be considered a fast cycle
vibration. This type of vibration is usually a drive train vibration,
things like the driveshaft, motor or torque converter. If the vibration
puts waves on the top of the water or splashes, this type of vibration
is a slow cycle vibration and usually is an axle or tire vibration.
People have trouble determining where the vibration in their vehicle is
coming from. Try the test below if your not sure.
JACK TEST
A simple way to do this
is out the vehicle in question up on jack stands (make sure the vehicle
is completely secure), run the vehicle up to the speed you have the
vibration. Make sure you use the brake to stop the drive train before
you put the car in park if it’s an automatic. If the vibration is a
fast cycle vibration you may want to have the DRIVESHAFT checked for
balance. This may make no sense to you but you may try indexing the
shaft 180 degrees (just pull the shaft off the rear yoke and put it on
the opposite way). What this does is change the resonant frequency
property of the driveline and in many cases it takes the vibration
away. If you have a slow cycle vibration take the tires off the car
(make sure you put lugs back on the axle to keep the brake in line) and
run the vehicle again. If the vibration is gone you now have to find
out if it’s the rim or the tire and good tire shop can help you with
that. This is a simple test for any vehicle but please if you’re not
completely sure of how to put the car on stands safely bring the car to
a certified technician to perform the test.


Drivetrain Components