Head flow thread, please post for all to see

[Mr DOHC]

i got a rep saying a thread about head flow properties should be made, so, here it is

perferably hard data, not your dads mate saying "it should flow 800hp now mate"
also, please quote who did it, and what stage they say it is, pics if u got 'em

Free flow cylinder heads in brisbane
stage 1
18RG 88270 head

inlet port
lift, cfm, hp
100, 33.46, 57
200, 72.85, 125
300, 114.28, 196
400, 128.56, 221
500, 135.70, 233

exh port
100, 30.60, 52
200, 59.99, 103
300, 88.92, 152
400, 111.42, 191
500, 114.28, 196


can you also post stock flow values

[jeffro ra28]

the heads we make at work flow 310 cfm on the exhaust and around 420cfm on inlet.

Some other important info to include with your flow specs is inches of water and flow range.

[Mr DOHC]

10" water for mine, and what u mean flow range?

[jeffro ra28]

when they flow your head, there are a number of selections for flow range. It should not effect the overall flow rating but is more or less a variable if you were to compare flow rates with that particular bench.