Here is what I think I have learned about this.
#1. A 292 at 3,000 rpm @ 100% effencicy would pump 255cfm and 204 cfm @ 80% VE. A 250 at 3,000rpm @100% VE would pump 217 cfm and @80% VE 217 cfm.
#2. From what I've read and been told both heads flow in the 170 cfm range stock and both can handle 1.84" intakes with minor un-shrouding. Another source said a stock 194 head will flow 178 cfm.
The numbers on Tom's site I believe are for "open"port heads but we can be conservative and use them anyway. When he went to 1.84" intakes and removed the bosses flow at .500" was 195.6 cfm a 25.6 cfm gain and with lumps 215.6 cfm . A 20 cfm from adding the lump to a head with the bosses already removed. In the second test how much was valve size and how much boss removal? We may never know. Based on what I've read in the past I would say that at least 1/2 of that gain was from removing the bosses. Tom says there is no gain adding lumps to stock valves but he didn't say there was no gain by removing the bosses with stock valves. So my guess would be there might be a gain of up to 32.8 cfm gain with boss removal and lumps with stock valves as opposed to 45.6 cfm gain with big valves.
That would put us at 202.8 to 210.8 cfm with stock valves, no bosses, and lumps
So I think removing the bosses and adding lumps (or not) to either head would work for you. A 194 head will give you a little compression bump. Lumps? If you've got'em use'em. I'm still looking into valve shrouding.
