Lt1 truck engine

Chevrolet has been in a clash with Dodge and Ford for a very long time now. The LT1 or the LS1? Both were available in the 90s Camaro and 90s Corvette.

The LS1 is word renowned for its power and reliability. InGeneral Motors created the all new LT1 small-block. The LT1 used a reverse-flow cooling system that cooled the cylinder heads first. This allowed for higher compression ratios which increased power output compared to its predecessors. All LT1s featured a cast iron cylinder block, with aluminum heads for Corvettes and Camaros, and cast iron heads for all other models.

The Corvette block featured 4-bolt main bearing caps, all other LT1s have 2-bolt main bearing caps. The LS1 was much more advanced than the outgoing LT1 engine. The LS1 featured an all aluminum block, and aluminum heads. This reduced weight significantly whilst increasing heat dissipation.

This allowed for more performance while keeping temperatures safe. All LS1s featured 6-bolt main bearing caps. More Chevrolet small block information is available on Wikipedia.

How much better was it though? Lets look at the factory LT1 Corvette and Camaro performance numbers:. Now lets look at the numbers for the same generation Camaro and Corvette, but with the LS1 engine. As you can see from these numbers, the LS1 is way more powerful. Not only does it make more peak horsepower, but it also makes more peak torque.

This is due to the massive advancements such as the distributor-less ignition system.The LS based small-block engine is the primary V-8 used in General Motors ' line of rear-wheel-drive cars and trucks. Introduced in Januaryit is a "clean sheet" design with only rod bearings, lifters, and bore spacing in common with the longstanding Chevrolet small-block V-8 that preceded it as the basis for GM small-block V-8s. The basic LS variations use cast iron blocks, while performance editions are all aluminum with cast iron cylinder liners.

Variants of the LT version of the GM small-block have been used since. Most of the credit for this engine family must go to Ed Koerner, GM's Powertrain vice president of engineering operations at the time. The performance improvements in the LS-family V-8s over the previous classic small-block V-8 family are several. The lower section of the block incorporates deep side skirts, along with 6-bolt cross-bolted main bearing caps.

This fully boxes the crankshaft, creating a very strong and rigid structure that has been hot-rodded by enthusiasts to over 1,HP. Although it is the same compact physical size as the classic small-block V-8, this block can accept a 4-inch stroke as an option in its stock form, due to the cam location being elevated slightly, compared to previous block designs.

Also, the cam bearing journals are larger, to allow for a higher cam-lift profile than was previously possible. The stock aluminum heads can provide a high amount of air-flow, which previously could only be found in aftermarket race-performance heads.

The aluminum heads also incorporate steam vents to prevent gas pockets from building up in critical areas, and this is vital in allowing the coolant to manage heat build-up for high-performance applications.

Such design features allow for a higher compression ratio with no fear of detonation. The thermostat has been located at a low position, which eliminates the possibility of a gas pocket preventing the thermostat from properly sensing the heat of the coolant. Previous generations incorporated a coolant passage through the intake manifold to warm the incoming fuel-air mixture in very cold climates. However, modern fuel-injection techniques eliminate fuel atomization concerns under all conditions, so the LS family uses a dry intake manifold.

This removes a common coolant leakage point and also allows the incoming air to remain as cool as possible for better power production. The architecture of the LS series makes for an extremely strong engine block with the aluminum engines being nearly as strong as the iron generation I and II engines.

The LS engine also used coil-near-plug style ignition to replace the distributor setup of all previous small-block based engines. The cylinder firing order was changed to so that the LS series now corresponds to the firing pattern of other modern V-8 engines for example the Ford Modular V The first of the Generation IIIs, the LS1 was the progenitor of the new architecture design that would transform the entire V-8 line and influence the last of the Big Blocks.

The Generation III 5. The extra horsepower was claimed to come from the intake ram-air effect available in the SS and WS6 models. The LS6 shares its basic block architecture with the GM LS1 enginebut other changes were made to the design such as windows cast into the block between cylinders, improved main web strength and bay to bay breathing, an intake manifold, and MAF-sensor with higher flow, a camshaft with higher lift and more duration, a higher compression ratio of The casting number, located on the top rear edge of the block, is The 4.

Catharines, Ontario and Romulus, Michigan. It uses flat top pistons.The original LT1 engine, available from throughwas only offered with two vehicles; the Chevrolet Corvette and the Camaro Z The LT1 offered increased horsepower and performance at the end of the muscle-car era and their horsepower saw a gradual decrease each year. The engine's short lifespan combined with limited production makes these cubic-inch engines much sought after.

Identifying the cylinder head casting number and the engine ID number should allow you to identify an LT1. Locate the ID number cast on the engine block on a machined pad towards the front of the engine.

The number is on the passenger side, near the cylinder head and is between seven to eight digits long. Remove the alternator if it blocks access.

lt1 truck engine

Decode the LT1 engine ID number. In order, the code identifies assembly plant, month, day, and engine suffix code. When cross-referenced against a Chevrolet listing, the suffix code gives exact engine specifics. Engine suffix codes matching these identify an original LT1 engine block. Remove one of the valve covers to access the cylinder head casting number. It is located on the cylinder head, usually towards the center.

lt1 truck engine

The casting code will be between six and seven numbers long and needs to be cross-referenced with a Chevrolet listing to verify it as a LT1 Cylinder head. When both component numbers match, it is most likely a genuine LT1 c. This article was written by the It Still Works team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information.

To submit your questions or ideas, or to simply learn more about It Still Works, contact us. Step 1 Locate the ID number cast on the engine block on a machined pad towards the front of the engine.

Be sure of the year vehicle if the engine is still installed. Cross referencing various ID and casting numbers contributes to an accurate identification as certain engine components may have been replaced. Because of its unique status, the LT1 was normally kept original.The LT1 engine is a small-block eight-cylinder engine that is produced by Chevrolet.

It is known for its high-performance and use in Chevy's line of Corvette, Camaro and Caprice cars. All LT1 engines are built from a cast-iron block.

The LT1's iron engine block is sized at cubic inches and has an overall displacement of 5. It has a cylinder bore and stroke of 4 and 3. The LT1 has a compression ratio of Power output of the LT1 varies slightly depending on the vehicle it is placed in. The LT1-equipped Corvette features horsepower and ft. Camaros and Firebirds with the LT1 engine generate horsepower and ft. Featuring a total of 16 valves, the LT1 has two valves per cylinder, each of which is made of cast aluminum. Fuel is delivered to the engine by way of an electronic fuel injection that sequentially serves fuel to each of the eight cylinders.


The LT1 has an aluminum intake manifold and a mm throttle body. This article was written by the It Still Works team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information.

To submit your questions or ideas, or to simply learn more about It Still Works, contact us. Valvetrain and Intake Specifications Featuring a total of 16 valves, the LT1 has two valves per cylinder, each of which is made of cast aluminum.

What are the Differences?

Chevrolet small-block engine

About the Author This article was written by the It Still Works team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information.New generations of small-blocks are generally accompanied by fanfare, ticker-tape parades, and claims of the greatest thing since Nutella hit sliced bread.

But will some ignore the Gen V release as a simple marketing ploy for an LS engine that just has its fuel injectors in a different place? That would be a poor choice on their part, because not only does the new LT1 differ significantly from all small-blocks before it and is easily the biggest thing since the LS1its advancements work together to simultaneously increase fuel efficiency, lower emissions, and bump power potential.

And while the Gen 5 is sure to bring new challenges to the aftermarket, so did the LS1… then as now, opportunity knocks for talented folks who are brave enough to blaze new trails. Of course, it never is C4 ZR-1 excepted. These needs comprise an engine that is not just powerful, efficient, and durable, but also compact and lightweight.

The pushrod architecture is a shoe-in for these final two goals as it allows for an externally smaller, lower-profile engine, yielding a drop in the center of gravity and a lower hoodline — hello badass handling and top-notch aerodynamics. In terms of output, the LT1 will make somewhere in the neighborhood of horsepower the final figure will likely be released about the time you read this.

Peak power numbers never tell the whole story of course.

How to Identify an LT1 Engine

Like the original Turbo-Fire, the Gen 5 is still a valve, cam-in-block degree V-8 with 4. Cues from the beloved LS-series are more apparent. Like the LS1, the Gen 5 LT1 features aluminum-block construction, 6-bolt main caps, and a composite intake manifold.

lt1 truck engine

The LT1 even shares the same 4. Yet the only physical parts that carry over from the latest LS motors will fit in the front pockets of your greasy garage jeans some miscellaneous bolts, piston pins, valve spring retainers and locks, and a crank key.

lt1 truck engine

The LT1 really starts upping the ante when it comes to new technology. This new fuel delivery system pays dividends in efficiency, emissions, and in helping to enable an aggressive compression ratio of GM has been in the business of DI for several years now, with its first application for the U. Owners of 3.

GM V LT1 Engine Details - Gen 5 Unleashed

Port Fuel Injection PFI systems, used on small-blocks ever since the Tuned Port Injection days, work by squirting fuel into the intake ports upstream of the intake valves. The combustion gases from the later injection of fuel will still be hot when they exit into the exhaust, which helps heat up the catalytic converter more quickly.

This gets the engine controller into closed loop quicker. Thank advanced technology and engineering for enabling such a high static compression number, while even allowing for use of octane gasoline on days you are feeling stingy hopefully those days are not track days - premium fuel will be needed to extract all ish horses. The first major enabler is the aforementioned DI, which is great at cooling the air-fuel charge since the energy to evaporate the fuel comes from the gas phase in the cylinder; with PFI, this heat energy came in part from the port walls and valves.

Taking the heat out of the gas rather than out of metal helps cool the charge, so you end up with cooler in-cylinder temperatures heading into the compression stroke. A lower-temperature starting point means the charge can be squeezed a bit more before the heat of compression sends pre-spark in-cylinder temperatures too high. Note how high the intake port openings are in the cylinder heads. To deal with all of this, main combustion chamber variables that needed to be tweaked included chamber size, injector nozzle and spark plug placement, valve sizes and angles, and the intricate facets of the piston crown.

According to Mr. The orientation of the valves is different too: each new generation of small-block has featured shallower valve angles than the previous, moving from 23 degrees on the original to 15 degrees on the Gen III and IV the LS7 was shallowest at 12 degrees.

The Gen 5 continues this tradition, with its intake valves being rolled to just a Hot rodders have long known that shallower valve angles allow for smaller-volume combustion chambers and help minimize valve shrouding as the valves near maximum opening, hence increasing breathing potential. Speaking of increased breathing potential, the use of DI also facilitated a higher-flowing, much straighter airflow path to the intake valve. With a PFI system, the fuel displaced some of the air, so the volumetric efficiency was worse by having the fuel run past the valve.

There are more firsts for small-block history in the LT1 head, as not only did previous-generation engines have equivalent valve angles on the intake and exhaust, the valve stems always occupied parallel planes in line with piston travel. Not so on the Gen 5, as its intake and exhaust valves are splayed angled apart 2. While this is a huge enabler for the aforementioned in-cylinder mixture motion, a side effect is its moving the valve stem tips further apart from one another.See all 18 photos.

Back in the smog-addled years of the '70s, a base Corvette wheezed through a Q-jet carburetor on its way to hp with a claimed 8. How far have we come? It's a brave new performance world out there. While power has admittedly come at the price of complexity, GM engineers have managed to produce truly impressive gains while also enhancing driveability, emissions, and mileage.

If that LT1 doesn't impress you, how about an emissions-legal supercharged LT4 that can make hp on pump gas? That's cause for celebration and perhaps a look into "How'd they do that? Accompanying this flood of creative combustion engineering is an avalanche of GM acronyms, some of which you may already know.

Let's start with GDI gasoline direct injection. This is the heart of Gen V. ETC electronic throttle control is one you should already be familiar with. Finally, VVT variable valve timing has also been around for a while.

GM started swinging the cam in the Gen IV small-blocks back in in search of better emissions, performance, and mileage. Before we dive inside the Gen V, we're gonna need a scorecard just to keep track of all the variants. There are more family members than just the headliner LT1 and LT4.

The littlest member of the Gen V family is the LV3 4. The 5. Keep in mind the current SAE horsepower rating system uses a more conservative correction factor, which reduces the power by roughly 5 percent compared to the traditional "hot rod" correction factor used in the performance industry. That puts the 6. Just savor that number for a moment, hp from a small-block workaday truck engine.

Adding 5 percent to the LT1's rating pushes it over hp. While some parts interchange, it's best to think of these engines as a whole new branch on the small-block Chevy family tree.

That's all because of requirements dictated by GDI. A trio of lobes located at the rear of the camshaft drives a mechanical fuel pump located on top of the lifter valley. This generates a maximum of 2, psi of fuel pressure plumbed directly into each combustion chamber. When the fuel hits the top of the piston just a few milliseconds before spark occurs, the fuel is instantly vaporized. This gives the engineers the ability to finitely control both the arrival time and amount of fuel to be mixed with the air in the cylinder.

This efficiency advantage is clearly announced by the LT1's This is unquestionably the highest compression ratio small-block GM has ever built for a production V Even going back to the original L Those older engines took advantage of this compression because of the availability of excellent, high-octane leaded pump gas. Today, octane is the best you'll see and that's available mainly east of the Rockies.

Despite this, GDI allows an engine like the LT1 to make outstanding power using this higher compression ratio.We know, advertisements are annoying and slow down the internet. Unfortunately, this is how we pay the bills and our authors. We would love for you to enjoy our content, we've worked hard on providing it. Please whitelist our site in your adblocker, refresh the page, and enjoy! The 6. That engine displaced 5. The new 6. It is part of a new Gen V small block family, with a cam-in-block architecture and 4.

Follow our coverage of GM LT1 engine news. The bore and stroke dimensions are: 4. It was refined and modified to accommodate the mounting of the engine-driven fuel pump and vacuum pump. It also incorporates new engine mount attachments, new knock sensor locations, improved sealing and oil-spray piston cooling. Oiling System : the oiling system is revised and features a new, dual-pressure-control and variable-displacement vane pump with increased flow capacity.

Variable displacement enables the pump to efficiently deliver oil pump flow as demanded. Dual pressure-control enables operation at a very efficient oil pressure at lower rpm coordinated with the Active Fuel Management and operation at a higher pressure at higher engine speeds providing a more robust lube system with aggressive engine operation.

The LT1 6. A dry-sump oiling system with a Oil-Spray Piston Cooling : All Gen V engines feature oil-spray piston cooling, in which eight oil-spraying jets in the engine block drench the underside of each piston and the surrounding cylinder wall with an extra layer of cooling, friction-reducing oil. The oil spray reduces piston temperature, promoting extreme output and long-term durability. The extra layer of oil on the cylinder walls and wristpin also dampens noise emanating from the pistons.

Rotating assembly and windage tray : within the Gen V block is a durable rotating assembly that includes a steel crankshaft and 6. The connecting rods have a new profile that enhances strength.

The pistons are lightweight, which enhances high-rpm performance, as they enable the engine to rev quicker. They also have a unique head topography that is essential to the direct injection system.