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Chevy 350 Engine Specs – What Year Is The Absolute Best?

Are you looking to buy a Chevy 350, the first-generation of Chevy small-block V8 engines? Many of them were produced, but what year is the best Chevy 350 engine?

Whether you need an upgrade or for other purposes, you deserve to know the difference.

The Chevy 350 engines comprise different engines with varying performance. Depending on what you intend to achieve with the new engine, you choose the one with the appropriate specification.

We will look at the specifications and performance of various Chevy 350 V8 engines. Read on for details and the information you need to make the best decision.

What Year Is The Best Chevy 350 Engine?

best year for chevy 350 engine
The best years of Chevy 350 engine are 1970 LT-1, 1992 L98, and 2002 L31

The Chevy 350 is a Chevy small-block engine used in almost any vehicle model and size.

Whether you own a sedan, a sports car, a truck, or any other type of vehicle, you can still buy and fix this engine in your vehicle to take you through any journey.

The Chevy 350 engines were redesigned and reworked after they debuted on the market in 1955. It has become simple to maintain and produces more performance.

The following are the best versions of the Chevy 350 that still remain popular among hot rod enthusiasts and car fans.

Read more: Chevy 350 vs. 305: Which Is the Better Engine For You?

1970 LT-1

1970 Chevy LT-1

The LT-1 became popular immediately after it debuted on the market in 1970. Its success in the market was remarkable.

The LT-1 was a marvel piece of engineering, featuring one of the ever-seen high-performance components and parts. It features a camshaft, solid filters, and a carburetor specifically designed with an aluminum intake.

Performance-wise, the LT-1 was a beast among its equals. It delivered a whopping 350 HP, making it the favorite engine for the 1970 Corvette. This power may seem like not much today, but it was a force to reckon with.

Despite the success of the Chevy 350 LT-1, it faced emission problems. Its power output had to be reduced from 370 hp to 255 hp in 1972 to comply with the regulations.

It further suffered from the more stringent emission laws that saw its power reduced to 145 hp in 1975.

The Chevy 350 LT-1 is, undoubtedly, one of the best fuel-guzzling engines of its generation.

The original versions were made in 1970. It held the record with a power of 370, which could propel you through any journey you set out for.

If it’s the high output power you’re after, then the L46, the 1971 LT-1, and the 1969-1970 L48 are the next best choices, with their horsepower coming in at 350, 330, and 300, respectively.

Read more: 2 Bolt Main vs. 4 Bolt Main: Which Is Better for You?

1992 L98

This version of the Chevy 350 will go down in history as the best-performing, eco-friendly engine. It maintained its relatively high power of 250 hp while remaining emission-compliant and fuel-efficient.

Compared to earlier generations of the Chevy 350, many car enthusiasts picked L98. As a result of its success, this particular engine remains one of the most popular Chevy 350 engines ever introduced to the market.

The Chevy 350 L98 has high performance while maintaining low fuel consumption because of a tuned-port fuel injection (TPI) system and aluminum cylinder heads.

These specifications made it deliver a power of 130 hp when it was first produced. The output power steadily climbed to 250 hp as the engine was redesigned for better performance in the versions released in 1992.

The L98 was mainly fitted in Corvette, Camaro, and Pontiac car models.

Due to its high output torque, fuel efficiency, and low emissions, it is by far our best choice of Chevy 350 engines.

It was suitable for street performance and won races. In fact, the L98 earned a spot as the basis for the Callaway Twin-Turbo package.

2002 L31

Being the latest Chevy 350 engine, you expect it to have the best-performing crate engine. The L31 is how it is referred to by the engineers, but its market name is Vortec 5700.

This Chevy 350 engine was mainly fitted under the hood of General Motors (GM) vans and trucks. It is unarguably the most reliable engine and has a 100,000-mile warranty on the entire engine block.

The L31 features cylinder heads with combustion chambers and intake ports similar to those in the LT-1. That makes it compatible with previous versions of small-block engines. Another highlight is the ease of upgrading.

The L31 can be easily fitted on all models of trucks, vans, and SUVs with the help of a professional mechanic. This versatility makes it the best engine that you need to upgrade your vehicle.

As the most recent Chevy 350 engine, L31 is readily available. People prefer it for its unrivaled strength, reliability, and durability. It produces a power of 255 hp at 4,600 rpm and 330 foot-pounds of torque at 2,800 rpm.

Today, you can choose an already used L31 or opt for a half-finished crate version.

Read more: GM 4.8 vs. 5.3 vs. 6.2: Which Engine Is Better?

Chevy 350 Overview

The Chevy 350 is a 5.7L, small-block, V8 engine featuring a 4.00-inch bore and a 3.48-inch stroke. The power output from this engine varies from 145-370 hp, depending on the generation or version.

They were fitted in different vehicle makes and models. Chevy 350 debuted in 1955 and lasted until 2002 when the last generation was mass-produced.

The engines were primarily fitted in GM’s full-size vans but could also be used in sedans, SUVs, and trucks.

It can still be found in different GM and Chevrolet vehicles.

Chevy 350 Generations Specs Chart

350 VariantsYears offeredSize (L)Horsepower (hp)Torque (lb.-ft.)Compression ratioFuel typeBore (in)Stroke (in)
L461969-19705.7 L35030011.0:1high octane gas4.003.48
L481967-19805.7 L300380 10.25:1gasoline3.983.46
L651970-19765.7 L2502558.50:1gasoline3.983.46
LM11979-19885.7 L1752508.2:1gasoline37363.48
ZQ31969-19745.7 L27030010.25:1gasoline4.003.48
LT-11970-19725.7 L37038011.0:1gasoline4.03.48
L821973-19805.7 L2502859.0:1gasoline3.53.31
L811981-19815.7 L1902808.2:1gasoline4.03.48
LS91969-19865.7 L1652759.1:1gasoline4.13.6
LT-91981-19865.7 L1602508.3:1gasoline4.03.48
L831982-19845.7 L2052909.0:1gasoline3.803.6
L981985-19915.7 L2453309.5:1gasoline4.03.6
L051987-19955.7 L2103108.3:1gasoline4.03.48
L311996-20025.7 L2553309.4:1gasoline4.003.48

Note: These specs are taken from the engine’s best performing year(s).

Chevy 350 Generations Details

1969-1970 L46

The L46 engine was primarily used in the Corvette between 1969 and 1970. This engine had many variants, some of which were found in the Camaro. L46 is a 5.7-liter engine that is part of the small-block engine series.

It was mainly identified by the casting number 186, 4-bolt mains, 2.02-inch intake valves and 1.6-inch exhaust valves, and a compression ratio of 11.0:1.

The L46 was a high-performing engine that required high octane gas. It produces up to 350 hp at 5,600 rpm and 380 lb-ft of torque at 3,600 rpm. L46 was the best of its generation.

With that massive power, you could use it to go anywhere regardless of the terrain. Though it was discontinued after just two model years of Corvettes, its performance was still good.

A video about the comparison between L46, LT1, and LS1.

1967-1980 L48

Camaro SS L48 engine
The L48 was exclusive to the Camaro SS for the 1967 model year.
Credit: commons.wikimedia.org

The L48 was the first 350 V8 engine produced by Chevy and debuted in 1967. It was exclusive for the Camaro SS for the 1967 model year before its use was permitted for other Chevrolet passenger cars and trucks.

The engine comprises cast pistons, a hydraulic cam, 4-bolt mains, and a compression ratio of 10.25:1. The L48 also featured a Rochester Q-jet carb that delivered a whopping 300 hp and 380 lb-ft of torque in 1969 and 1970.

But due to the tightening of federal laws on emissions and fuel economy, the output power was significantly reduced. The ones made in 1971 only had a compression ratio of 8.5:1 and a power output of 210 hp.

As a result, its use in trucks ended because it could only propel the Corvette. That made GM research different ways of getting the most power out of their engines. Other changes fluctuated the power output of this engine in the subsequent years until it dropped to 190 hp in 1980, its final year of production.

1970-1976 L65

The L65 is a 2-barrel Rochester carburetor version of the L48 350 engine. It debuted in 1970 with an output power of 250 hp fitted in the Camaro.

Its performance slightly dropped to 245 hp in 1971, which further dropped to 165 hp due to the same stringent emission regulations. Between 1973 and 1975, the output power dropped to 145 hp.

The L65 350 V8 engine was produced from 1970 to 1976. At that time, the torque provided by the engine was about 255 lb-ft.

1979-1988 LM1

The LM1 is one of the best 4-barrel 350 V8 engines ever fitted to Chevy’s passenger cars and trucks. It was a popular engine in the 1970s and the better part of the 1980s.

The LM1 could produce 155-175 hp but only with a Rochester Q-jet carburetor. The specific output power depended on the version year and the vehicle model where it was fitted.

They were optionally available under the hood of Chevy passenger vehicles and the Camaro Z28. The LM1 engines were last used in passenger vehicles in 1981, after which they were mainly left for police interceptors until 1988.

They became obsolete when the L05 350 V8 engines were introduced in the same year.

That happened after GM stopped supplying its V8 engines larger than 5.0 liters to the market, reserving LM1 for high-performance cars such as the Corvette, Camaro, Pontiac Firebird, and Trans Am. LM1 used mechanical ignition points, electronic or computer-controlled spark systems, and feedback or conventional carburetors.

These components were never redesigned or replaced throughout their lifecycle.

1969-1974 ZQ3

This is the standard engine under the hood of the 1969-1974 Chevrolet Corvette.

It is also a 5.7-liter small-block Chevy 350 engine series capable of delivering 300 hp of power. It was fixed with a Rochester “4MV” Quadra-Jet 4-barrel carburetor and an L48 camshaft and had a compression ratio of 10.25:1.

The performance of the ZQ3 was reduced in 1971 to 270 hp and a torque of 300 lb-ft with a lower compression ratio of 8.5:1. Federal regulations forced a further drop in performance in the following year to 200 hp and a net torque of 270 lb-ft.

The ZQ3 still faced challenges complying with the emission regulations, which saw a further power reduction to 190 hp in 1974 when it was last produced. The ZQ3 produced after 1971 used a thicker cylinder deck and low nickel content.

There were no other design changes for units made in 1974. They had small heads, were lightweight, crack prone, and less high-performing than the previous versions that used higher compression ratios.

1970-1972 LT-1

Camaro Z28 LT-1 engine
LT-1 engine was considered the ultimate small-block V8 engine when it first debuted in 1970. Credit: commons.wikimedia.org

The LT-1 engine was considered the ultimate small-block V8 engine when it first debuted in 1970. It was only fixed on the Corvette and second-generation Camaro Z28.

The engine was robustly built with the following features:

  • 11.0:1 compression ratio;
  • Delco transistorized ignition;
  • LT-1-specific aluminum intake manifold;
  • Holley 780cfm 4-barrel;
  • High-flow, low-restriction ‘rams horn’ exhaust manifolds.

The LT-1 delivered 370 hp in the Corvette and 360 hp in the Z28. The two versions were capable of 380 lb-ft of torque at 4,000 rpm.

The high performance could not be maintained for long. The no-lead gas, insurance issues from the insurers, federal smog regulations, and fuel economy mandates forced GM to redesign it.

The compression ratio was also reduced from 11.0:1 to 9.0:1 in 1971, resulting in a horsepower of 330 hp and torque of 360 lb-ft. In 1972, the net power became 225 hp with a torque of 280 lb-ft.

These adjustments were necessary for the engine to be fueled by low-octane, no-lead gasoline. High-performance engines could be knocked out prematurely if they run with that low-grade fuel.

Also, the low output power was necessary for insurance companies to charge car buyers fairly because they based their rates on the engine’s size and performance.

1973-1980 L82

The L82 also became an instant success when it debuted on the market.

Some of its features include the following:

  • 2.02-inch intake valves with 76cc combustion chambers;
  • Rochester Quadra-jet 4-barrel sitting on top of a split-plenum aluminum intake manifold;
  • 9.0:1 compression ratio;
  • Forged aluminum pistons and an aggressive hydraulic cam.

The L82 350 V8 engine that debuted had a net power of 250 hp and 285 lb-ft. But due to the government-mandated emission regulations, the output power had to be reduced to 205 hp and 255 lb-ft.

GM found ways of improving the performance of L82 while still remaining in compliance with the federal regs. That resulted in an improved power output of 225 hp in 1979. During the last year of production, engineers were able to get 230 hp from the L82.

Such units were only fitted on the Corvette and Camaro Z28s.

A video about the L82 engine.

1981-1981 L81

This was the only Chevy 350 V8 engine under the hood of the 1981 Corvette. It had a low compression ratio of 8.2:1 and performance of 190 hp and 280 lb-ft, the same as L48. What made the difference was the hotter cam and computer-controlled spark advance in the L81.

The L81 is also unique because of the Smart Carb that it uses. This is a redesigned Q-jet with electronic mixture control that gets instructions from the engine control module (ECM) to read oxygen sensors in the exhaust stream.

L81 is a transitioning engine with an electromechanical fuel system. We can only imagine how fuel tuning and keeping them tuned was a challenge. The designers used traditional carburetors instead of modern-day computerized injectors.

1969-1986 LS9

LS9 engine
LS9 had a power output of 165 hp at 3,800 rpm and torque of 275 lb-ft at 1,600 rpm. 
Credit: commons.wikimedia.org

LS9 was a truck engine that used a Rochester 4 BBL carburetor. It had a power output of 165 hp at 3,800 rpm and torque of 275 lb-ft at 1,600 rpm.

The LS9 debuted as the highest performing small-block engine offered by GM, and it instantly became the standard engine in the C6 Corvette ZR1. People highlighted its civility at low speeds and remarkable tractability at all RPMs.

LS9 had titanium forged rods, forged pistons, titanium valves, and a dry-sump oil system that made it a stunning piece of engineering. It was just not easy to resist this engine back in the day.

1981-1986 LT-9

The LT-9 was the truck version of the engine, fitted in K20 and K30 pickups, passenger vans, and cargo vans.

This engine had a compression ratio of 8.3:1, a Rochester Q-jet carburetor, and 4-bolt mains and could produce 160 hp at 3,800 rpm and 250 lb-ft of torque at 2,800 rpm.The LT-9 was mainly fitted in heavy vehicles with a gross weight of 8,500 lb.

1982-1984 L83

The L83 350 V8 engine was the last available for us in the third-generation Corvette in 1982. This same engine was available for the new fourth-generation Corvette.

Its main differentiating feature is the twin-throttle body fuel injection system that replaced the carburetor in older Chevy 350 versions. With the new fuel injection technology at its infancy, engines, where they were deployed, could only make it above 205 hp and 290 lb-ft of torque.

That could be considered as an average performance compared to its predecessors.The cross-fire injection system used in the L83 engines was also not easy to tune, ran soft, and idled fast.

It was replaced by the new tuned port injection system (TPI) in later versions of Chevy 350 engines made from 1985.

1985-1991 L98

1985 L98 engine
L98 was the standard engine installed in the Corvette between 1985 and 1991. 
Credit: wikipedia.org

This is the first Chevy 350 V8 engine to use the TPI instead of a cross-fire injection system. L98 was the standard engine installed in the Corvette between 1985 and 1991.

TPI was considered the most advanced fuel injection system in the history of GM V8 engines. It relied on the ECM and controllers to process the readings from various sensors required to monitor fuel through sequential port injectors. Unlike other Chevy 350 V8 engines whose performance was reduced over the years of production, the L98 recorded a steady increase in performance.

The net output power is as follows: 230 for 1985-86, 240 hp for 1987-89, and 245 hp for 1990-91. Features of L98 included the following:

  • An optional performance axle ratio of 3.08:1 with a 5 hp bump starting;
  • New hydraulic camshaft with roller lifters to reduce friction;
  • TPI fuel injection system.

The L98 engine became available for use in the Camaro Z28, IROC-Z Pontiac Firebird, and Trans Am in 1987.

But if you needed it for IROC or T/A, you had to choose the 5.0 TPI (305cid) since GM had not made a 5-speed manual transmission to handle the high torque produced by the 5.7 TPI engine.

A video about the L98 engine.

1987-1995 L05

The L05 Chevy 350 engine debuted in 1987 primarily for Chevy, GMC, and Hammer trucks and SUVs. It was fitted in the Chevy Caprice in later years when it was designed with a roller cam instead of the conventional flat-tappet cam.

The L05 was also in Buick, Cadillac, and Oldsmobile before its production halted in 1996.

The features of the L05 engine include the following:

  • 64cc combustion chambers;
  • Swirled intake ports;
  • A single belt (serpentine belt) accessory drive.

1996-2002 L31

The Vortec 5700 or L31 is a 5.7-liter Chevy 350 engine designed for trucks. It marked the end of Chevy’s generation I small-block engines.

It was fitted with the same cylinder heads, combustion chambers, and intake ports as the LT1 V8 engines.The difference is the reverse flow and higher compression ratio that LT1 has. Those features make it a perfect upgrade from older versions.

The L31 requires up to 8 bolts for attaching the manifold, which is fewer than the 12 bolts you would usually need for other small-block engines. This engine produces 255 hp at 4,600 rpm and torque of 330 lb-ft at 2,800 rpm.

L31 was fitted in 1996 G-Series vans, Oscar Mayer Wienermobile, and Isuzu box trucks.

Conclusion

With the information in this article, you can now make the best decision when buying Chevy 350 engines.

The L98 is the most recommended Chevy 350 engineas it is an all-around good engine.

It delivers 250 hp, a better performance than other engines in this series.

The L98 also has high output torque, fuel efficiency, and low emissions, making it car enthusiasts’ favorite.

Read more: Best Duramax Engine: What Are the Best & Worst Years?

Author

  • Randy

    My name is Randy Worner and I am the founder of chevygeek.com. I have been working on cars and trucks for almost 45 years. For the last 36 years I have taught Automotive / Diesel Technology classes for UTI, Snap On Tools, Chrysler, Pepboys, Lone Star College, NAPA and TBC Corporation. I also own a technical writing company known as Supreme Technical Services. It is ASE Gold Seal certified and Blue Seal Certified Author of auto/truck repair information.

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2 thoughts on “Chevy 350 Engine Specs – What Year Is The Absolute Best?”

  1. HELLO RANDY,
    MY NAME IS DAN AND I RECENTLY PURCHASED A 1966 CHEVY C20 FROM AN ORIGINAL OWNER BUT THE PROBLEM IS HE PUT A MADE IN MEXICO CRATE MOTER IN IT CASTING # 10066036. I DONT KNOW MUCH ABOUT IT AND THERE’S NOT MUCH ABOUT IT ON THE INTERNET. HOW CAN I FIND OUT WHAT WATER PUMP TO USE ALTANATOR ETC. I BOUGHT A NEW WIRING HARNESS FROM BROTHERS TRUCK ALONG WITH NEW HEI DISTR. ETC. ANY HELP WOULD BE GREATLY APPRECIATED.
    DAN ODOWD ( 760)702-1335

  2. hi ,i just boug ht a 1993 chev. 4×4 ,700 auto trans ,runs very nice.i,ll be flushing the motor,trans just rebuilt. What could i resonably expect for fuel economy ,on the highway at 60 m/p/h on a sunny,windless, 70% day ? Thanks for the info

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