You can manage to get an 1100 to rev pretty easliy and it has a heaps of torque. I can take off in 3rd easily. All you need is a medium cam, i used a wade 104. I also changed to a nissan bluebird distrubitor on my ex gf mini and it screams off 7000 revs tacho.
If you want fuel injection go for a weber style throttle body. the twin and single point injection are not very good they are for emissions. Single 1 1/2 or 1 3/4 su works better.