Bob,
I agree 100% that GM had engineers that knew what they were doing and I
agree that the ride height affects the items you noted. However, I'd really
like to know just how much the front to rear drop affects those items.
Front to rear drop can be calculated as follows:
Front ride height 13 1/8 inches
Rear ride height 11 11/16 inches
13 1/8 - 11 11/16 =
13 2/16 - 11 11/16 =
12 18/16 - 11 11/16 = 1 7/16
That distance between the drop can be calculated on a 26 foot GMC as
follows:
Wheel base = center of front axle to center of dual bogies = 160 inches
Center of front axle to center of front slot = 24 3/8 inches
Center of dual bogies to center of rear slot = 56 3/8 inches
160 - 24 3/8 + 56 3/8 = 192 inches = 16 feet
Therefore if my math is correct we have a drop of 1 7/16 inches over 16
feet.
I don't have the skill to calculate the effects of that drop on the factors
you noted.
However, since one does not have to have any skill (or intelligence) to
express an opinion here goes. I'd say that if one sets the ride height front
to rear level with the front axles level and can get 5° degrees of caster,
0° degrees of camber, and 0 toe in/out I believe a GMC will steer, stop, and
handle OK.
As noted in an earlier message I will conduct this experiment the next time
I'm in the USA which will probably be the spring of 2012.
As noted in many of my messages, PLEASE feel free to ignite what I've noted
above using a flame thrower!
Regards,
Rob M.
Sydney, Australia
-----Original Message-----
From: Bob de Kruyff
Set the coach to the heights mentioned in the shop manual per the slots in
the frame. This is not to be taken lightly since it affects the roll center
height, the weight distribution, the airbag pressures, front joint angles,
brake balance, and so on. Do you think GM just pulled these numbers out of
their ..s?
--
Bob
I agree 100% that GM had engineers that knew what they were doing and I
agree that the ride height affects the items you noted. However, I'd really
like to know just how much the front to rear drop affects those items.
Front to rear drop can be calculated as follows:
Front ride height 13 1/8 inches
Rear ride height 11 11/16 inches
13 1/8 - 11 11/16 =
13 2/16 - 11 11/16 =
12 18/16 - 11 11/16 = 1 7/16
That distance between the drop can be calculated on a 26 foot GMC as
follows:
Wheel base = center of front axle to center of dual bogies = 160 inches
Center of front axle to center of front slot = 24 3/8 inches
Center of dual bogies to center of rear slot = 56 3/8 inches
160 - 24 3/8 + 56 3/8 = 192 inches = 16 feet
Therefore if my math is correct we have a drop of 1 7/16 inches over 16
feet.
I don't have the skill to calculate the effects of that drop on the factors
you noted.
However, since one does not have to have any skill (or intelligence) to
express an opinion here goes. I'd say that if one sets the ride height front
to rear level with the front axles level and can get 5° degrees of caster,
0° degrees of camber, and 0 toe in/out I believe a GMC will steer, stop, and
handle OK.
As noted in an earlier message I will conduct this experiment the next time
I'm in the USA which will probably be the spring of 2012.
As noted in many of my messages, PLEASE feel free to ignite what I've noted
above using a flame thrower!
Regards,
Rob M.
Sydney, Australia
-----Original Message-----
From: Bob de Kruyff
Set the coach to the heights mentioned in the shop manual per the slots in
the frame. This is not to be taken lightly since it affects the roll center
height, the weight distribution, the airbag pressures, front joint angles,
brake balance, and so on. Do you think GM just pulled these numbers out of
their ..s?
--
Bob
