Morning everyone. My head porter just called me & gave me my numbers. I don’t know much about head flow so here’s what I got. 1970 1231786 heads Stage 1 valves. Bowl clean-up Back cut/valve angle work Port work I believe done on a Superflow bench @28”. Intake: .100 .200 .300 .400 .500 69 133 176 201 227 Exhaust: .100 .200 .300 .400 .500 75. 114 148 165 184 Do these seem like pretty decent flow numbers for iron heads? Let me know what you guys think. Thanks, Kyle
Those numbers sound typical for just bowl bend work on these heads with stock size valves and It looks like now up to .400" lift you now have a 85% Exh to Intake ratio so you should steer away from a duel pattern Cam in this build especially if your planing on running headers. One thing that does concern me a tad is that the smaller Exh valve is flowing more then the Intake at .100" lift If you run a 450" to .470" lift Cam then the motor should make 360 to 400 hp depending on the Cam you run if you have over 400 cid and a 9.5 comp in the Bores!
Just for comparison's sake, Out of the box aluminum TA Stage 1 SE heads with just a good valve job have base flow numbers of 290/205 @ .550 lift. with just entry level porting, you easily get over 300 cfm on the intake side. Have a look at this thread, http://v8buick.com/index.php?thread...r-gessler-level-3-ported-iron-stage1s.267528/
Thanks guys. I know you guys love your aluminum heads & for good reason. I understand completely. With my iron heads I may not be where the guys with aluminum heads are, but all in I'm at roughly $1,600-$1,700 with my iron heads which is way cheaper than the TA heads but a bit over Edelbrock & other brand aluminum heads. Kyle
These are the flow numbers from a pair of 1786 heads I had Greg Gessler port for me a few years ago for comparison. These were mid-level porting, and I think Gessler offered two additional levels of port work, each flowed better, and each a bit more costly. While these heads would support more, my cam selection was rather tame. 220 degree intake duration @0.050" / 228 degree exhaust duration @0.050" / 0.315" I and E lobe lift.
Greg also recommended those Level 3 heads for the heavier street cars like the Rivieras running cast exhaust manifolds. Tommy
Please let's get one thing straight here gang, that being that it's not 100% all about sheer air flow numbers in and out of a given motor that makes it Perform well by any means, it's also very much about having the highest average amount of port velocity to enhance the rpm range that the Cam was made to run in!