1.94 Valve in Chevy 305 Heads (416 castings)

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Carnut1
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Re: 1.94 Valve in Chevy 305 Heads (416 castings)

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Bob Hollinshead wrote: Sat Aug 28, 2021 12:27 pm
Carnut1 wrote: Sat Aug 28, 2021 12:19 pm
Bob Hollinshead wrote: Sat Aug 28, 2021 12:10 pm you could look for a 434 casting head, they were on the 267 or 262 engine of the mid/late 70's. It's an odd ball head-for some reason when GM casted this head they made it way thicker than the 305 castings. They aren't scalloped around the outer head bolt areas and will take a 1.94 valve easy with unshrouding, They end up with around 64cc chamber when done. The ports are also thick enough to be ported to the 170cc range easily.
For an experimental 331 I once did a set of 434 heavy cast set to 2.055/1.6 valves. I did go through one of the bowls and welded it up. The second time I went to update the porting I ruined them. It was a street runner and had issues with traction but ran very well for what it was. Thanks, Charlie
Charlie, did the 434 casting appear thicker than the typical 305 castings in your opinion? I don't know what molds they used to cast these with but they carried over the exterior design of the pre-lightweight heads for sure. I carved on a set years ago and there was all the metal there that I needed-engine ran good and is still going.
It was a heavy casting.
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Carnut1
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Re: 1.94 Valve in Chevy 305 Heads (416 castings)

Post by Carnut1 »

Most 305 castings are very light.
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Re: 1.94 Valve in Chevy 305 Heads (416 castings)

Post by Walter R. Malik »

Carnut1 wrote: Sat Aug 28, 2021 4:40 pm Most 305 castings are very light.
The original 305 castings from the late 70's had 350 water jackets and were VERY thick around the chambers.
Almost impossible to find these days.

Realistically they were 350 - 2 barrel heads with a smaller, revised chamber.
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