Stroking A 350 To 377: Is It Possible?

The 377 is a high-revving engine that can be built from a 400 small-block engine with a 350 crank. The 377 has a bigger bore than the 350, allowing for better cylinder filling as the valves are less shrouded. The 377 is a popular choice for those who want to rev their engines hard and are not concerned about low-end torque. It is also a good choice for those who want to reduce the weight of their engine, as the 350 crank is lighter than the 400.

A 377 is a 400 small-block with a 350 crank

The 377 is a combination of a 400ci engine block and a 350ci engine crankshaft. The 400ci bore is overbored by 0.030 inches to 4.155 inches, while the 350 stroke is 3.48 inches, resulting in a displacement of 377ci. This combination has been used in high-performance racing applications since the late 1970s.

The main journals of the 350 crank have an outside diameter of 2.45 inches, while the 400ci main bearing bores measure 2.65 inches in diameter. This discrepancy requires the use of spacers to correctly fit the standard 350 crank into the 400 block, unless an aftermarket crankshaft is used.

The 377ci engine offers improved cylinder filling due to its larger bore, which reduces valve shrouding compared to smaller bore sizes found in 327, 350, or typical 383 engines. This engine combination is particularly well-suited for road racing applications where high RPMs are desired.

However, some enthusiasts argue that the 377ci engine is not a significant upgrade over a standard 350 or 383 engine. They claim that the extra cubes gained by using a longer 3.75-inch 400 crank would provide more benefits than the marginally better bore-stroke ratio of the 377.

In conclusion, the 377 is a unique engine combination that offers certain advantages, especially in high-RPM applications, but it may not be the best choice for everyone, and careful consideration should be given to the intended use and available parts before committing to this build.

The 377 has a bigger bore than a 350, allowing for better cylinder filling

The 377 is a popular choice for those who want a big-bore/short-stroke combo, as it yields 377 inches when combined with a 0.030-inch overbore (4.155 bore, 3.48 stroke). However, it is important to note that the 400 uses larger-diameter main bearings than other small-block Chevys, so special thicker bearings are required when putting the smaller 350 mains into the larger 400 block. Most 377s use either 350-style 5.7-inch rods or aftermarket 6-inch rods, and performance piston manufacturers offer off-the-shelf pistons for this combination.

While the 377 has its advantages, some argue that there is no replacement for cubic inches, and a 400 block with a longer stroke crank will result in more power. Additionally, the 383, which is a more common choice, can spin just as fast as the 350 and make more power doing it. Ultimately, the best option depends on the specific use case and budget, as both the 377 and the 383 have their pros and cons.

The 377 is a high-revving engine

The 377 engine has a bigger bore which allows better cylinder filling as the valves are less shrouded than in a typical 4.030-inch bore, as found in a rebuilt 327, 350, or typical 383. The 377 engine is also a good option for those who want to fit a cubic-inch rule for racing.

The 400-block uses larger-diameter main bearings than other small-block Chevys. There are two options for putting the smaller 350 mains into the larger 400 block: spacer bearings used in conjunction with stock-style bearings, or special thicker bearings. The 377 engine usually uses either 350-style 5.7-inch rods or aftermarket 6-inch rods.

The 377 is a good choice for a light car

The Rotax 377 is a 35 hp (26 kW), twin-cylinder, two-stroke aircraft engine, that was built by BRP-Rotax GmbH & Co. KG of Austria for use in ultralight aircraft. It is a good choice for a light car for several reasons.

Firstly, the 377 has a two-cylinder design, which makes it a relatively compact and lightweight engine. This can be advantageous for a light car, as it can help improve fuel efficiency and handling. The engine has a dry weight of 38.4 kg (84.6 lb), which includes the reduction drive and exhaust system.

Secondly, the 377 features piston-ported, air-cooled cylinder heads and cylinders, which provide effective cooling. The engine can be cooled using either a fan or free air, depending on the specific application. This cooling system helps to maintain optimal operating temperatures and prevents overheating.

Thirdly, the 377 has a single Bosch Flywheel Magneto Generator 12-volt ignition system and is equipped with a 36 mm Bing double float carburettor. This carburettor can be operated with either a hand lever or cable choke, providing flexibility in usage.

Additionally, the 377 has a power output of 26 kW (35 hp) at 6500 rpm, which offers a good balance between performance and efficiency. The engine also has a power-to-weight ratio of 0.67 kW/kg (0.41 hp/lb), indicating its ability to deliver a significant amount of power relative to its weight.

Furthermore, the 377 uses regular gasoline with an octane rating of at least 90 unleaded. This fuel type is readily available and suitable for a wide range of applications, making it convenient for users.

Lastly, the 377 has a reduction gearbox with a Torsional shock absorber and offers multiple gear ratios: 2.00 to 1, 2.238 to 1, and 2.58 to 1. This allows for flexibility in terms of power delivery and can be advantageous for light cars that require different gear ratios for optimal performance.

The 377 is a good choice for a car with steep gears

The 377 is a good choice for steep gears because of its higher bore/stroke ratio, which will allow the engine to rev higher. This higher revving engine will be able to take advantage of the steep gears and provide more power and acceleration. The 377 is also a good choice for a performance engine as it has a bigger bore, which allows for better cylinder filling and less shrouding of the valves. This can result in more power and better performance.

The 377 is a good choice for those who want a high-revving engine. The shorter stroke of the 350 crank allows the engine to rev faster as there is less rotational inertia. It also puts less stress on the rods and pistons as velocity is decreased at equal RPMs. The 377 will have a higher redline than a typical 400 engine, which means it can be pushed harder and achieve higher speeds.

The 377 is also a good choice for those who want a unique engine. The 377 is not as common as other engine choices, such as the 383 or 400. This can make the 377 a more interesting and distinctive choice for car enthusiasts. Additionally, the 377 can be a good choice for those who want to build an engine themselves, as it requires some custom parts and modifications.

Overall, the 377 is a good choice for a car with steep gears due to its higher bore/stroke ratio, performance potential, high-revving capabilities, and unique characteristics.

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