endurance without an Arab

["T J Habberley" <T.J.Habberley@btinternet.com>]

Im sure their are others out there who compete on something other than an
Arab. Im currently competing at Silver level (40 and 50 mile set speed
rides ) in the UK on a Welsh Cob. I hope to go further eventually. I would 
like to exchange info on feeding and differences in performance. My
problems/ advantages are as follows: My horse is cheap to keep , he cant
take much grain and comes out in protein lumps on high energy/fibre mixes
any one had the same problem? The down side is that it makes it harder to
give enough energy in feed for longer rides. His energy levels seem to
differ from an Arabs, it comes in short burst at a high speed , a slowing
down and then another short burst . He can do this over 40 miles and
complete in the required time  Any one else have similar?
  He chills out at final vettings ( after all hes done his job) which gives
a low pulse unless Iv screwed up on the ride, but panics vets who seem to
expect every horse to leap about a lot...
Any advice , comments ( polite please ) eagerly sought.