781 BBC flow numbers
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781 BBC flow numbers
Can someone help me I am looking for stock, or mildley ported 781 BBC heads with stock valve size flow numbers. Any help would be great!! THANKS, CHRIS
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-what is a 781? oval port or rectangular port? what era? what size valves?
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-Thinking it may be an oval port head from the 1960's and 70's:
-at 25" test pressure-
-at -----------------.100", .200", .300", .400", .500", .600"-
int-stock------------ 65----134----180---205---225----255
int-mild ported------65----134----192---230---250----264
exh stock------------54-----97-----120---149---169----186
exh mild ported-----62----109-----144---177---196----204
-This is with stock size valves, something like 2.060" and 1.72"
-------------------------------
-Thinking it may be an oval port head from the 1960's and 70's:
-at 25" test pressure-
-at -----------------.100", .200", .300", .400", .500", .600"-
int-stock------------ 65----134----180---205---225----255
int-mild ported------65----134----192---230---250----264
exh stock------------54-----97-----120---149---169----186
exh mild ported-----62----109-----144---177---196----204
-This is with stock size valves, something like 2.060" and 1.72"
-
- Guru
- Posts: 2650
- Joined: Sun Sep 05, 2004 6:38 pm
- Location: salt lake city, ut
- Contact:
hello chris....781's are oval port bbc oc w/ approximately a 265cc runner and came stock w/2.06 int and 1.72 exh as bill said, ....heads were cast in 1974 for 454's....fyi they respond well to 2.19 int and 1.800 exh and mild port...last set i had flowed 262 int and 197 exh stock,...i have seen chambers from 113cc to 118cc...work great on 470ci or less...hope this helps,....bob
stand on it!
Link to some flow numbers
Chris,
here is a link to some BBC flow numbers. Watch them though because...some of the exhaust are with flow tube on exhaust. They don't actually show the 781 but I think the 049 is pretty similar and the flow numbers are there for that one. But as it looks the guys have already responded to your question. It is still a good link! http://www.chevyhiperformance.com/techa ... ndex8.html
here is a link to some BBC flow numbers. Watch them though because...some of the exhaust are with flow tube on exhaust. They don't actually show the 781 but I think the 049 is pretty similar and the flow numbers are there for that one. But as it looks the guys have already responded to your question. It is still a good link! http://www.chevyhiperformance.com/techa ... ndex8.html
Link to some flow numbers
Chris,
here is a link to some BBC flow numbers. Watch them though because...some of the exhaust are with flow tube on exhaust. They don't actually show the 781 but I think the 049 is pretty similar and the flow numbers are there for that one. But as it looks the guys have already responded to your question. It is still a good link! http://www.chevyhiperformance.com/techa ... ndex8.html
here is a link to some BBC flow numbers. Watch them though because...some of the exhaust are with flow tube on exhaust. They don't actually show the 781 but I think the 049 is pretty similar and the flow numbers are there for that one. But as it looks the guys have already responded to your question. It is still a good link! http://www.chevyhiperformance.com/techa ... ndex8.html