the 416 heads are super for the small 283/307 motors, have a set on my 307. On it, with the 58cc chambers, the c.r. is bumped up about a point or more-really improves performance. Free usually means $ to get them in shape, you need to set a limit on how much to spend on them.
Is there really any advantage other than comp by using the 58cc 305 heads on a 283 rather than the PP 283"s? Lippy
The 1.84" intake valve would be the main one, and the 35 year old heads might be less beat than the 60 year old heads.
I put a pair of these on a 283 I built for a buddys '59 Chris Craft. These and a little cam really woke it up. There are a few reasons to use the in place of the 283's. Intake valve size and hardened exhaust seats are two. Gene.
416's have better runners than a lot of old Chevy heads. If you don't mind replacing the seats with larger seats for 1.94" or 2.02" valves they really let the engines breath with the right cam swap.
I think I read (somewhere) that going to 2.02" valves, rather than stopping at 1.94" can be a bit counterproductive in the 416 heads. Thought was that the 2.02" intake becomes rather shrouded and as a result doesn't really flow any better than the 1.94". I built a mild 283 and used them as a low-cost way to increase compression. I also built a 305 for the front engine dragster I just finished and used the 416 heads. When I had the heads freshened I did spend a few $$ to have the stock 2-piece valves swapped out for one piece stainless valves. The ultimate decision though rests with what the intention is for the engine. Street use with a bit of bump in power might be fine, but for some wild thoroughbred of an engine something really performance oriented might be a better way to go. Let your intentions and wallet be your guide. Lynn
I've seen the top of the cylinder clearance before. My opinion only, but the 305 head has hardened seats, better flow, same combustion chamber size, and accessory holes. Big win.
Yep, and they are really good for low end torque on a 350, IMO. We put a set on a 350 we built for a '63 K10, and loved the way it pulled from just off idle through 3500 or so. It broke both rear tires loose on pavement at will, and threw large roosters of mud at friends 3.73's and a very mild cam, Ed Performer and carb. Check for cracks.
The bore of a 305 Chevy, that 416 heads come off of, is quite a bit smaller than the bore of a 283....so no, there's no issue there. Lynn
305 heads never came with 2.02 intakes. 2.02 valves and 3.785 bores do not work well together. The 1.84 intakes and hardened exhaust valve seats will work quit nicely in a 283.
Valve seats that handle today's gas without getting the hell beat out of them is the big thing. Good compression and they flow decently on older small small blocks is the other. They just have zero bubba factor when someone looks at the engine.
Yes, when these heads are fitted with 2.02" valves a good machine shop will always open up the combustion chambers to unshroud the larger valves. So it will also increase combustion chamber size a little too. Same way Chevy did the chambers on old camel hump 2.02" heads also. It's a pretty simple process to make the cuts on 8 chambers on a mill.
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