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Engine technology is both a passion and an obsession for car engineers and car aficionados alike. This is due to the fact that the modern internal combustion engine is an imperfect design and could benefit from a few tweaks to squeeze out more power and efficiency from the system.



The Vortec line of cylinder heads was introduced by GM in 1988 as a V6 with a 4.3-liter displacement. This technology created a vortex or pressurized swirl of fuel and air mixture inside the combustion chamber that enables the engine to produce more power while still gaining a marginal amount of fuel efficiency.

Vortec Means Power

Vortec heads instantly added 55 or more horsepower to a regular 350 head with the same displacement. Automotive enthusiasts are quick to note that the 350 and the 5.7 Vortec are essentially the same engine with the same displacement. The 350 designation is the cubic inch measurement that also translates to 5.7 liters.

It is hard to tell the two cylinder heads apart when it comes to the physical aspect of the build, but there are major differences that make Vortec heads more powerful and efficient.

5.7 Vortec Heads and Regular 350 Heads

The intake port of the Vortec head is different and measures 160cc with a modified port that increases the flow velocity. The bowl area is wider around the guide compared with regular 350 heads.

The intake bolt pattern is different and utilizes an eight-bolt attachment. The bolt pattern and the number casting is the quickest way to differentiate a Vortec Head from a regular 350 head. The Vortec head is available in two casting numbers (10239906 and 12558062) that offer identical performance virtues. You can also check the casting mark on the end of the head and check for three triangular saw-tooth casting marks that indicate Vortec potency.

Vortec Intake Valve Seats and Combustion Chamber

The intake valve seat of the Vortec head has a three-angle grind straight from the factory and the combustion chamber design is a radical departure from former GM heads utilized in the market. The Vortec combustion chamber is a kidney-shaped design that promotes better combustion and will have the spark plug located near the center of the chamber.

The regular 350 head utilizes a 90 degree intake bolt angle while the Vortec makes do with a 72 degree bolt angle. Experienced mechanics are all too familiar with the lay out of a Vortex head as all the attachment bolts point straight up when the head is bolted to the engine.

Conclusion

The Vortec head is without a doubt engineered towards producing more power, torque and engine response while improving overall fuel economy. If you plan to change or modify the head of the 350 engine in your car, installing a Vortec head alone will yield positive effects in your quest for power and speed.

A 350 Chevy engine may be any engine built by Chevrolet with an approximate displacement of 350 cubic inches. These engines were in continuous production from 1967 to 2002, with the last member of this series being the Vortec 5700. The Vortec 5700 appears in full-size Chevrolet trucks from 1996 to 2002. A modern 350 Chevy engine uses a harmonic balancer, also known as a crankshaft damper, to reduce the vibrations that occur when the crankshaft rotates rapidly. The crankshaft damper is a weight on the end of the crankshaft under the crankshaft pulley.

Instructions

1

Disconnect the central mounting bolt and washer from the crankshaft balancer with a socket wrench. Remove the mounting bolts from the pulley, and detach the pulley from the crankshaft.

2

Attach Tool J23523F to the crankshaft balancer. Pull the crankshaft balancer from the crankshaft.

3

Record the length and position of any weight pins in the front groove of the crankshaft balancer. This ensures the crankshaft balancer is properly balanced when you replace it. Remove the weight pin from the crankshaft balancer.

4

Place the weight pins in their original positions on the crankshaft balancer. Apply a thin layer of Adhesive 12346141 to the keyway on the crankshaft balancer to seal the crankshaft joint.

5

Align the keyway of the crankshaft balancer with the woodruff key on the crankshaft. Press the crankshaft balancer onto the crankshaft with tool J23523F. Mount the crankshaft pulley to the crankshaft, and tighten the mounting bolts for the pulley to 43 foot-pounds with a torque wrench.

6

Mount the central bolt and washer to the crankshaft balancer so that the crown of the washer faces away from the engine. Tighten the central bolt to 70 foot-pounds with a socket wrench.

A 1970 Pontiac 350 is a common term for a 1970 Pontiac Firebird with a 350-cubic inch engine. This car used a mechanical fuel pump with a single action diaphragm to deliver fuel to the engine. A push rod between the camshaft and the fuel pump rocker arm operates the fuel pump. The fuel pump in a 1970 Pontiac Firebird is not adjustable or repairable, so you must replace it when it fails.

Instructions

1

Disconnect the fuel intake line and the fuel outlet line from the fuel pump on the lower right side of the engine. Close the open end of the fuel intake line with a clamp.

2

Remove the bolt from the right front mounting boss with a socket wrench. Fill this hole with a longer 3 / 8 inch bolt to hold the push rod for the rocker arm in place.

3

Disconnect the mounting bolts and washers for the fuel pump with a socket wrench. Detach the fuel pump and gasket from the engine.

4

Coat the mating surfaces of the new fuel pump and the engine with sealer. Install the new fuel pump and gasket to the engine, and attach the mounting bolts and washers for the fuel pump.

5

Remove the temporary bolt in the right front mounting boss, and connect the permanent bolt with a socket wrench. Remove the clamp from the fuel intake line, and connect the fuel lines to the fuel pump. Check the fuel system for leaks.