Magnum head porting for the beginner
Then grind on either side of the canal, like below. Stand the head on end, for easier access.
Blue sharpie shows blend line I ground to. Check from port opening to make sure of your work.
Now for the test:
.050 49.9 well, that felt good, didn't it!
.100 79.0
.150 109.8
.200 142.6
.250 172.6
.300 194.1
.350 216.5
.400 235.2
.450 243.8 < just about 33 cfm from stock, and you can use a cam up to .500 lift
.500 229.6 Don't let the dip in flow bother you, you want to over-shoot your
.550 228.5 max flow so you can take advantage of it. Valve spends very little
.600 226.3 time at max lift. Anything below that, the valve is there twice!
Final port cc's 165.8
stay tuned, exhaust is on the way !
Then grind on either side of the canal, like below. Stand the head on end, for easier access.
Blue sharpie shows blend line I ground to. Check from port opening to make sure of your work.
Now for the test:
.050 49.9 well, that felt good, didn't it!
.100 79.0
.150 109.8
.200 142.6
.250 172.6
.300 194.1
.350 216.5
.400 235.2
.450 243.8 < just about 33 cfm from stock, and you can use a cam up to .500 lift
.500 229.6 Don't let the dip in flow bother you, you want to over-shoot your
.550 228.5 max flow so you can take advantage of it. Valve spends very little
.600 226.3 time at max lift. Anything below that, the valve is there twice!
Final port cc's 165.8
stay tuned, exhaust is on the way !
