Z250B rebore

I am currently doing up a 1980 Z250 as a classic club racer. Does anyone know what capacity the barrel can be bored out to and where to get the right pistons?

Even if you find a proper rebore kit see how much you will gain. A .030 inch over bore on a 360 cubic inch V-8 only yields about 5 cubic inches, (a 360 cubic inch motor is 5.7 liters). Not much of a gain for the price, plus you will have to have it re balanced to match the larger piston. Jim Beam is brown.

Hi and welcome

Check out the MOMS section for historic rules and I believe you get a 5% tolerance. If you're reboring for power gain, fitting a larger engine would be a better option, if you're reboring due to damage/wear etc, might be cheaper/easier to get another barrell.

http://www.ma.org.au/fileadmin/user_upload/Documents/MOMS/2010_MoMS_Files/2010_MOMS_16.pdf