can network establishing -- Can bit timing

Hi,

I am working on a CAN network where i have 20 nodes attached to my network.

Speed = 125 Kbps
Clock = 8 MHZ (I can increase it further if required)
Nodes = 20
Cable = 120 ohm characteristics impedance.
Drop Length per node = 2 meter
Total length of cable network = 80 Meter

1> Now how can i set the Bit timing for my CAN network so that with this
topology it works at 87.5% sample point ?
One experience person told me at 125 KBPS we can cover :--

   - 500m length total.
   - Double the length of drop down cable.
   - Maximum length of drop should be 120M
   - Also for every connector consider 6 meter loss in length.

2> Please suggest is above calculation right?
3> If not then what eactly should i keep the value of propagaton segment of
my network?
4> Also what value to be kept for phase segment 1 & 2 ?

I am also refering an1798.pdf for it.  But i need some to share his
experience in setting CAN network .

//Eric