You may need to watch for the accessory bolt holes in the front of the heads. The fuelie heads don't typically have any.
From a purely traditional point of view; this would be the best reason to use them. On the 67 and 68 350's, the camel hump heads were standard, the true "fueler" heads were not used after the 65 Corvette, but the same castings were used on the 66 and 67 L79/327 and 67 and 68 Z28 302's.
They will physically bolt on since they use the same gaskets and manifolds but the older heads don't have hardened valve seats for the newer unleaded fuels. That can be done when the machine shop rebuilds the heads but it can get more expensive than using the later heads. Just something to consider.
I have done this many timesand as an added benefit the 327 heads run cooler. 350s are designed to run at 220 degrees for emissions but the 327s run at 180. The difference is in the water passages.
Just had an engine built doing that. I had camel hump heads reworked (new hard seats and 3 angle valve job, and fit to a 350 block. Runs really good on the test stand. I didn't want the accessory holes in the heads as I am building a sorta early style truck.
In my previous post I failed to mention that the 327 was still available for the 1969 model year, they were a pretty low hp engine but they did use the same basic heads (accessory bolt hole style) as the low hp 350's in 69.
There is a point to take notice of there. The early heads did not have hard seats and were not designed for unleaded or worse yet ethanal gas. That gas can be hard on early (pre mid 70's ) valves and seats that weren't set up for unleaded.
I’m running em on 350. Had seats put in due to vehicle weight (school bus) but I’ve ran non hard seats without issues on regular rides. Accessory holes? I didn’t need em.
#461 casting 327 "double hump fuelie" heads on a 350 Chevy. I retained the hole-less 'vette valve covers by adding a fill tube to the Edelbrock Perfrmer intake, and drilling a PCV hole in the intake between the carb & distributor.
186 Heads are the last of the good camel humps and have accessory holes, used in 69 and 70. 68 heads are one year only as they have no accessory holes but have a port in between the exhaust ports for a temp sending unit to screw in. Earlier heads don't have the port and the temp sender goes into the intake manifold at the front. Also with Chevy small blocks, 302/327/350 all used the same base block casting so all the heads will interchange for the most part with little to no issue barring the seats as mentioned above. The rotating assembly of crank/rods/pistons is where the size difference comes from. Really any small block head will interchange and bolt on, just some combos are just better to be never done.
I know this is a revised old thread...but on the hardened seat discussion. I have a set of camel hump heads (no accessory holes) at the machine shop now. I wanted to have hardened seats installed, and the machine shop advised against it. They said, that it is too common that they cut into the water jackets turning the head into a door stop.
True...I ruined a set of 292 Turbo heads that way...and you won't realize it till you have them on the motor and try to run it.
Unless I missed it, did no one mention the combustion chamber size difference? Compression will be raised about a full point if I’m not mistaken.
Disclaimer/ I don't-consider myself an expert on the subject, just what I have gathered. Far too many combinations/application/hp ratings even during a single year for both 327's and 350's to use the term "standard". The "true" camel hump heads (through 1968) were used on 302's, 327's and 350's, commonly known as "461", "462" and "291" depending on year, some carried over also. There were some slight chamber shape differences in the 63-66/67,68 castings but as an example the 327/350 hp engines through their four year run were basically the same. Where the big confusion lies is when the later "accessory bolt" castings ("186" style) with the much smaller humps are called out as camel hump heads, I think these are what you might be comparing, the 69 large journal 327's did use the acc. bolt heads.
I'm running small chamber 59cc camel hump 2.02 heads on my 350 with flat top pistons to get the engine up around 10.75:1 CR, and they work great. That's something you need to check if you don't want high compression using older heads on a later 350. If having to run high octane gas isn't what you want be sure to calculate compression once you figure out chamber CC volume.
Depends on the year and the HP rating. Some early 350 have the 64cc already. Some 1971-73 have 72 cc, but most '72-later through the smog era 1986 are 76cc, with some even being as big as 80cc. Rough rule of thumb on 327-400" SBC's is 1cc equals about 0.1 points of compression.....so swapping a 64cc head in place of a 76cc head raises compression just over one full point.
The Jalopy Journal
