Your buddy may have numbers mixed up on the 601 casting. WOT AFR was 12.8 with this set up and i did add some jet to it as my plugs with the last jetting on this build were snow white with No color anywhere. Looks like a proform body but is the factory 4779 750 double pumper. This carb has shown 10HP more than my other carbs on many combo's it is a fully modified 4779 double pumper with larger venturies and thinned throttle shafts and rounded epoxied openings. Yes I have ran the same carb many times and the same dyno was used. You know all these things go through your head I feel down on power low speed TQ mostly with these Vortec 906 heads. They could not keep up with ported double humps with 1.94-1.50's to. In fact the trick flow and Edelbrock RPM heads needed worked over back then also. His sportsman II heads were 64cc and out of the box stock and that was back around early 90's.
Those Sportsman II heads do not work too bad They performed exactly the same as a set of ported 76cc chamber heads I built for a buddy. Trying to get some buddies together to do a test and tune grudge night race night at Thunder Valley here. I am curious if this larger cam 305 head will make the same or less power than the vortec and 228 -.495" lift roller cam. 480" lift cam flat tappet hydraulic and 601 heads. I have another date with the dyno and another 350 of mine with 288 norris with. I am hoping for mid 12's at the track with this combo. 050 cam and went 11.94's with the comp magnum 292H and 601 heads with 1.94-1.50 valves. Last time out with same vehicle it went 13.50's with the 268H cam and small valve 601 heads. Intake side is better than my old school heads. 500" lift and 174 on the exhaust at the same. I hear ya on the porting I ported mine and brought up the flow and you are correct the exhaust side sucks just like all GM iron heads. If you want a good Vortec head get the 185 cc runner head, bolt them on as they are light years over the 062-906 ones. 9.8 358 pump gas with those sportsman heads running 11.40's, 20 years ago I would have said no way. I don't care what the dyno says, the track tells me if I made more or not. My best set yet are my Sportsman II that I ported up. I have ported a set or two of 034 Bowtie heads that just blow Vortecs out of the water, so take it for what it's worth. The good thing from Vortec to the old camel hump heads is that the Vortecs make way more tq. Once you do that, then the Vortecs work pretty well for a production heads. With a better valve job and some minor port work I have got almost, now here is the kicker, the exhaust ports SUCK on these heads and need a lot of work than the intake side. 500 lift then stalled, there was one mod I did that boosted them to 248 by that alone.
Well, I have tested several sets of Vortec heads over the last decade.
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