camshaft for torque

[lobster]

ok my last post was a little general to say the least,so ill start on the basics

(this is for a 350 chevy sb by the way)

being a series III landy my 'racer' is quite heavy. obviously being a heavy off-roader while being used for daily driving it needs a short duration cam with buckets of torque. BUT ill be doing rallies etc. so ill be reving it at times too, so just a little top end power would be good (max 5500 rpm)

having looked around/read the tech, i was thinking of....
around 112 lobe separation
215 degress duration at 0.050
270 duration
0.500 lift

any particular makes to go for? Crane or Comp Cam prehaps.
will i loose a lot of top end power if reduce the duration by 5 or 10 degrees for more torque and mid power? is this combo ok as a start point?
cheers guys