Just wondering what proportion of early holden owners with original / period look cars still run stock heads and use some form of valve saver lube v's heads converted to run unleaded. I had mine converted it seemed sensible but i don't have a low milage, completely original, unrestored car that deserves to be preserved in its original form. Is anyone still running leaded heads ?

Got a couple of 30 year old VLs, so they have the hardened seats from factory, but have several mates with earlier cars that have put VL heads on them, or converted to EFI top-ends.

If you're not worried about keeping it original, but don't want huge hassles, the EFI 304 top end is an easy enough conversion (legality wise) but the costs do add up when you factor in exhaust work, cam, wiring etc.
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It wasn't just valve wear, pinging was a big problem too.
I wonder if it is worth worrying about really too. Use premium unleaded to stop pinging. I guess if your re-building an engine it's crazy not to put inserts in the valve seats though.
I miss not seeing a nice grey pipe after a long run in a car though.

It wasn't just valve wear, pinging was a big problem too
recurb the distributor and retime the engine blokes have doing that since the 80's.
Blokes that build hot 308's don't use inserts because they don't fit.

Yeah but if you re-graph and change the timing to counteract lower octane fuel causing pinging, you will lose power. The only way to fix the lower octane and keep power is to increase octane as far as I am aware. Lower octane fuel makes less power and is for lower compression motors. Pinging is actually pre-combustion caused by the higher original compression. The higher octane premium and I am fairly sure some lead replacement additives increased octane.
I used to add Flashlube to our on farm bulk petrol drum for any petrol motors here. I haven't used it for years and I haven't had any motors fail due to valve issues.....yet.

All our Ford from 1974 on F100's 250 6 cyl and V8 302 351 were a heavy duty engine had hardened valve seats, but not the Falcon engines.
Valiant had the same in Dodge trucks with that type of heavy duty 245 hemi.

I don't see why the L34 valved red V8 heads would be any different to blue or black, only that the unleaded 5.0L should have them as standard or they are flame harden around that spot as they did with the 1973-4 USA Cleveland heads when they went to unleaded fuel.
The 1973-4 chev heads would be the same.

Maybe some people could get away with the old standard valve heads if they drove easy with unleaded, but a lot of 6 cyl blue heads suffered from the valve seats wear, some say that the castings were of a softer cast iron then the red ? or were being just being flogged harder.
a lot of red 202 would burn out valves but my HQ 202 did 98,000 miles with no problem at all but it was flogged hard and I have seen people who drove slow with them burn valves, maybe due to it running too lean.

If running unleaded with std old valve and heads and maybe better to go a bit richer as well to drop the heat created, one with a standard blue motor should get away with running 91 octane unleaded and maybe re curb the dizzy a little bit where it needs it. 95 would be better fuel but for the forking out the extra cost.