I've read of people using 416 heads in Chevy 350s after having the original 1.84" intake valves swapped out for 1.94" valves (and the necessary machine work done to the heads to be able to do this). If you do this and then port the heads following a 416 head tutorial (like I've seen on here) can you get performance anywhere near what you can out of a set of aftermarket aluminum 350 heads with 2.02" intake valves, such as Flotec or Edelbrock heads? I found a site that gives head flow figures for factory and after market heads, but is just shows figures for ported 416 heads with 1.84 valves.

 

Not really.

Done WELL, you get performance roughly equivalent to 350 heads with 1.94" valves, not aftermarket ones w 2.02" valves. They end up potentially somewhat equivalent to some of the old double-hump heads like 186, or newer ones like 083.

 

Thanks for the info. I figured the same, but I thought I'd throw the question out there just in case I was wrong.

 

Been there. Along with a bumpier stick,



Some of the aftermarket options could be better for a 350. There are limits to what can be pulled through the runners, even with port relief. This is about as far as I dared to go:

 

Lost a lobe there, huh?

 

Find a set of World Products "Torquer 305" heads.
The valve centerlines are relocated to minimize bore shrouding and the heads already come with 1.94 / 1.5 valves.

Trick Flow also has heads specifically for the 305.

 

As I recall. the lobe was still there, or at least all the material needed for a lobe was in the oil filter. Pennzoil.

 

Except as I originally mentioned I have a 350. I'm hearing good things about the inexpensive "Deepmotor" heads you can buy on ebay. They are no doubt Chinese castings, but I suspect even the expensive big name companies like Edelbrock are having their heads cast there even though they may assemble their heads here in Merca, land of tariffs.

 

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