The best thing to do here is make sure the valve seats are in decent shape and seal properly and leave them alone. That’s worth 10-12 hp with no other changes.īut the real beauty of the Vortec is its additional airflow even using 1.94/1.50-inch valves. By simply adding a 64cc chamber head, the compression jumps to 9.6:1. Loose production tolerances often limit these engines to barely 8.0:1. In most production 350 Chevys, this is actually high. If we use a stock composition gasket at 0.041-inch thick with a 76cc chamber, we end up with a compression ratio about 8.5:1.
Let’s assume that your 350 comes with typical four-eyebrow pistons that measure about 0.020-inch down from the deck. With the smaller 64cc chamber Vortec heads, this means more power. This was done to reduce compression so that Chevrolet could achieve the emissions requirements. Nearly all traditional heads for a mid-70’s and later 350 c.i.d. Let’s start with the first benefit to using these heads - the smaller chamber. You can still find these heads in the junkyard but be careful as engines with a long service life can suffer cracks that make them unserviceable. This smaller chamber helps add power by adding compression. It demands its own, specific intake manifold and features smaller 1.94/1.50-inch valve sizes and a compact 64cc chamber. The Vortec head is a bit of an offshoot from the traditional small-block Chevy head. Produced was the Vortec that came on truck engines from 1996 up through when The best iron production cylinder head that Chevrolet ever But aftermarket heads cost money that you don’t The more air the heads can move through the combustion space, the more The biggest item that will improve power is a good set of But we’ll play along and assume the short block is sound. A ridge of any thickness means the cylinder bore is worn and the rings won’t seal and all your money spent on good parts will only pressurize the oil pan when that cylinder pressure leaks past the rings. If you can feel a ridge, then you are wasting your time to attempt to make power. That means you can’t feel an edge at the top of the cylinder wall from bore wear. Let’s start by assuming (here we go) that your short block is in decent shape. In our experience, you must have a decent set of cylinder heads in order to make 400 hp on a basic, low-compression 350 c.i.d. The advent of modern engines that make 400 hp or more has colored the reality of the past. It’s not easy to make 400 hp with a basic 350 Chevy using stock heads. Of course, adapting an LS to your truck would be expensive and not part of your plan. That’s not what you asked, but that would be the easiest way to achieve 400 hp. Frankly, the easiest way to make 400 to 425 horsepower would be to buy a 5.3L truck engine and put on a carbureted intake manifold, a 750 cfm Holley carb, headers, and stick in a mild hydraulic roller like Summit’s Stage 2 truck cam with 218 degrees of duration. Jeff Smith: Before we get started, let’s just say that the terms “lots of horsepower” and “cheapest” are at opposing ends of the same discussion. I’d like to put this engine in a ’69 C-10 pickup to terrorize the streets. I really don’t know what it was originally in but I’m pretty sure it was a truck. How would I do that? I have a 350 Chevy truck engine short block with a one-piece rear main seal. I want to build the cheapest, least expensive small-block 350 Chevy that can make around 400 to 450 horsepower. Our total investment was a little more than half the cost of a set of aluminum aftermarket heads.
This is a set of Vortec heads we’ve modified by machining the guides, and adding bigger springs, a set of Summit stainless steel valves, and ARP screw-in studs.