Stupid Tuning Question

["Robert Berning" <RobBerning@msn.com>]

I have a 1972 mgb, I got it running pretty good, but it very litely back 
fires when I shift, and if I let of the gas and coast in gear.  I would guess 
it is timing so I have been playing with that, but it also could be the SU 
carbs.

This leads to my second question,  I am not familiar with MG timing 
or SU carbs.  Is there a good book or books you can recomond for these?


Thank you!