You should be able to pull the vacuum based on cam more then anything,
port size in the head is a sepperate issue, . what are you using this for?
street car, drag car, 1800 lbs or 3800 lbs??????
The stroke on a 598 makes a big demand on the cylinder head, .
why Iron ??? class rules ???
john,
the RFD 24* -
http://raceflowdevelopment.com/RFD-h...ock-victor.htm
Just made 1098 hp with a single cast intake on a 565 @ 7800 rpm, ..
6.9's in a dragster, . .
1050 hp on a mild 582 with an un-ported cast intake, ran 7.0's @ 188
in a 4 link dragster, will go 6.9's with tuning
"pro" version with copper seats & titanium valves flows 490 cfm
and is looking to make 1200 hp on a 522" for NMCA, ..
Curtis