SQUEEZING POWER FROM THE MGB’S B-SERIES ENGINE

Last month I covered some of the history of the BMC B-series engine and introduced some details of the heads that can be found on the 1798cc version commonly found in the MGB. This time I want to detail some of the modifications that can be done on the original cast iron cylinder heads and what sort of improvements they deliver. It is worth noting that these modifications are also relevant to the 1489cc, 1588cc and 1622cc B-series engines in other MGs and BMC cars.

MGB five-port cast iron cylinder head

I mentioned previously how the BMC Special Tuning Department’s tuning booklet for the MGB stated ‘polish the ports for three bhp’ was pitiful, and how this was thrown into doubt even in the 1960s by specialist tuners’ cars. What I will now cover will comprehensively blow that BMC statement