273 Commando 4 Speed with Brewer Performance Replacement Clutch

I'm not sure why you're expecting a big increase in power when you're losing compression by going to the 318 block. Are you replacing the pistons?

Not expecting a huge increase in power, however the people that have done a similar 'upgrade' have noted that there is a noticeable difference. I stated 320HP / 340TQ which is probably above and beyond what's to be expected, better to make enquiries based on more than less, no...?