Stock Vortecs out-flow stock camel hump heads. Plus the vortec combustion chamber is a more modern high-swirl design which is very efficiant. There's a ton of them in boneyards as compared to camelhumps. Also since the camel hump heads haven't been made in 30+ years, what supply that is left has already been rebuilt/trashed a couple of times at least. Besides, everybody selling camel hump heads seems to want a lot of money, even for ones that need rebuit again.
There are draw backs to the Vortecs too. First is the intake bolt pattern, 8 bolts vs 12 on a non-vortec SB. You have to get a Vortec intake. Edelbrock makes at least 5 versions, GMPP has 2 and Power Plus has a couple too. However, one untapped source for Vortec carb'd intakes is the Marine industry. Mercruiser, volvo-penta and I think one other have sold 350's under there own brands that had Vortec's and ran q-jets. These used a Cast Iron intake with the right vortec intake bolt pattern. They pop up on ebay fairly regularly, you just got to search for them. They are usually cheaper than the other ones mentioned.
The other main drawback is valve retainer to valve guide clearance issue. This is when the spring is fully compressed (valve open) if the lift on the cam is too much, the retainer will hit the top of the valve guide. Most report max lift with stock vortecs can't exceed .490". If your cam is smaller than that no problem. If it is larger you got to machine the guides down and use smaller aftermarket seals. At the same time you should open up the spring pocket to allow the use of regular size SB springs. (Vortec springs are slightly smaller in diameter). You can get a tool from one of the cam compaines to do both jobs or have your machine shop do it for you.
If you are looking to install the heads on a fairly stock engine the vortecs would give the most bang for the buck. (small cam, no mods needed to the spring/guides). Surf ebay or the Marine shops for the intake.
I'm getting ready to actually remove a set of Camel-back heads from the 327 in my dad's 57 Nomad to replace them with Vortec's. Yes the camelbacks have been on that engine for 35+ years so they probably are quality cores to rebuild, but they don't have the hardend exhaust seats and would still need work done to them. I got a set of Vortecs for next to nothing and he sent them out to get the guides machined and spring pockets enlarged. Put them back together with stock valves and Z28 spec springs and they are ready to go($110 for the work done). He found a GMPP intake on Ebay for about $125 (less than half the dealer list price). When we swap the heads we will ditch the 60's style "30/30" solid lifter cam for a L-79 Hydraulic (.448 lift). All in all, we should have about the same power with better drivability over the 60's vintage stuff. All total, we've got less than $300 bucks in the parts to convert to the vortecs. Shop around, there are better deals to be had on Vortecs than the old camelback stuff.
