trying to figure out a cheap way to bump up compresion in my 318

[440charger68]

so i bought some 340 x heads and i just found out i will lose power if i add them to my 318 cause of the big combustion chambers i will lose compression and power. So what can i do to my original 318 heads to bump up compression? basically how much do i have to shave until i get about 9.5 or 10-1 compression or

[Ghoste]

If my memory serves (and I hate to admit I'm too lazy to look it up at this exact moment), that isn't your only issue with putting 340 heads on a 318.  I seem to recall something about notching the block to allow valve clearance. (and I will look it up shortly)

[chargd72]

I suggest finding a set of cast 302 heads for around $75.  They have a smaller combustion chamber and will bump your compression up to about 9:1.  When you have the money, these heads respond well to porting and bigger valves.  Later on, find some flat deck pistons to finish the job.