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Another update. Delta Cam should have the camshaft finished today, or Monday next week. Hope to receive it the week after. Lifters are also still on the way.

Been busy working on the GMC. The exhaust is pretty much finished. The O2 bungs were welded on for me - beautiful work. If this exhaust ever rots out, I'll let her TIG weld the whole exhaust for me

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The O2 sensor and the gauge are installed and it all works.

Been busy with the carburetor - managed to score a 500 cfm Holley locally for cheap. Basically a brand new carburetor. It has 61 jets now, which are probably too small. I did some looking around on the forum, most seem to use 68s for the 305. Pete said that the stock 73s worked well with the 478, so that's what I'm using as a baseline. Should it run too rich or lean, I can adjust jet sizes according to the O2 sensor readout.

On Amazon, they said that they shipped the jets to the Netherlands, turns out they do not. So have to ask some local guys if they have Holley jets.

It also has a no. 8 power valve, ie. it opens at 8" Hg. From what I've read the power valve should open at half of your idle vacuum, so 8 seems about right. It also has the stock 30cc accelerator pump.

This does mean that I'm plugging off the governor line, which I first intended to keep in place. I am playing around with the idea to hook a normally open oil pressure sender to the governor line, and if it senses oil pressure a buzzer would sound indicating you hit the redline. Though a nice tach would be better. Would love to have a nice vintage tach on the steering column. Any tachometer recommendations, let me know.

Made a nice adapter flange to use the 478 manifold, but am running into hood clearance problems with the propane mixer. Decided to go back to the 305 manifold, and use the available Mr. Gasket adapter. I'll be sure to radius the edges in the manifold to allow for more flow to the middle intake runners. The port size is the same on the 305 vs the older 478 manifolds. The difference is the carburetor bolt pattern and the 478 manifold has a built-in spacer - see picture.

Since the Holley uses the standard 5 1/8 air cleaner base, readily made propane mixer adapters are available, so I bought one and modified it somewhat to reduce the height. I corrected the center bolt hole and also made a bushing to better accept the 1/4 thread diameter and nut on the Holley. See picture.

I am resizing the pictures for the forum from now on, so they should enlarge quickly now. Took a while to load before!