Problem: What Is LS7 Lifter Preload? How To Check Right

Putting the correct preload is important in promoting your car’s running efficiency. The LS7 lifter preload is a product developed to provide more air and energy to be pushed into the car engine.

Nevertheless, LS 7 lifters are not convenient for all cars or vehicles, depending on their different designs and structures.

Here we will discuss actual lifter preload and how to approach stock lifter preload right.

What Is LS7 Lifter Preload? 

ls7 lifter preload

The 7LS lifter preload indicates the total amount of tension between the car pushrod and lifter, which is conducted through the construction of 7LS.

You only install the ideal lifter preload for your car when you focus on measuring the exact tension through the impact of oil pressure and the type of car engine.

Once you attain the right value of the genuine LS7 lifters and BTR LS7 lifters’ preload, the ability to control air and energy into the engine through your car’s lifter is really effective.

You can also read compulsory requirements regarding preload or travel lifters in manufacturers’ manuals or get them from the official websites of your automakers.

This can help you save much time calculating a lifted preload due to the values available before.

We assure you that you used to come across some versions of LS lifter preload in the market, particularly LS1 and LS7.

The “LS” has been popular for over twenty years and has been integrated into car engines to adopt basic demands for running and especially help you to save a lot of fuel.

Why Is Lifter Preload Important For Vehicles?

The role of the lifter preload in the vehicles’ preload is positively significant.

Manufacturers create lifter preload to expand the ability of the lifter plunger, automatically decreasing about 0.050 inches for the lifter structure to address some issues.

It helps maintain the engine’s working efficiency in a good situation when it approaches the normalized temperature.

The drop in lifter can explain this compensates for the total amount of piston oil used while supporting your car’s engine.

The high-quality performance lifter is only attained when no extreme lifter preload occurs in your car’s engine.

Too much preload can damage the performance engine due to having relatively great friction with the family of engines by forcing mental components against each over for a long time.

As a result, it can cause accelerated wear and tear quickly and even break down anytime.

Many engineers also consider that excessively high temperatures caused by the lifter preload lead to a loss of compression in the cylinder head without addressing it comprehensively.

Common Methods To Approach LS7 Lifter Preload 

lifter preload

You can use the two popular methods below to approach LS7 lifter preload effectively and simply

We will not discuss hydraulic lifter operation in detail; we only focus on adopting the hydraulic lifter piston (traditional solution) and Comp Cams tool (high-tech solution). In particular:  

High-tech Approach Towards LS7 Lifter Preload

You try to apply an adjustable pushrod (or shorter pushrod) to approach the lifter preload flexibly. This method is called a three-quarter-turn technique or high-tech solution for all cars’ engines.

You should prioritize using the Comp Cams tool to modify the pushrod checkers or the range of pushrods in the appropriate scale.

The value recommended for checking the pushrod is about a 0.050-inch change in length, making it easy to set the pushrod length quickly.

Traditional Approach Towards LS7 Lifter Preload

If you do not have experience in using common pushrods or narrowing differences in pushrod length, you should get a traditional approach by using a preload piston for the total process of discovering LS7 lifter preload.

This suggestion is taken for the demand to limit the amount of oil underneath the piston, which removes the maximum amount of air outside your car’s engine.

Then, the speed of valve life attains a high RPM. You should understand that the traditional method is based on less oil, indicating less air under the piston.

Kinds Of LS7 Lifter Preload

When considering the types of LS 7 lifter preload, you must catch the two basic lines covering LS7 mechanical and hydraulic lifters.

Here is a summarized look at them that you can overview for your car.

LS7 Hydraulic Lifters

LS 7 Hydraulic lifters benefit from pressurized oil’s special ability to modify the piston’s motion, ranging from the low to top level, which can constantly occur until the camshaft can activate them.

Many professional engineers support that the power is distributed equally in the standard cylinder head, leading to efficient performance.

The hydraulic lifters are under the impact of the traditional methods in approaching preload in the engine system; thus, most drivers can be familiar with how to use hydraulic lifters.

LS7 Mechanical Lifters

Mechanical lifters have lifter springs, levers, and arms to convert the force from the rotation into vertical motion under the support of the camshaft.

The amount of energy and air is calculated relatively exactly through the mechanical operation without considering too much effect of the piston in your car’s engine.

Remember that these values are estimated for each combustion chamber whenever the engine revs down and up.

Outstanding Symptoms Of Too Much Lifter Preload 

Too much lifter preload can impact the quality of your car’s engine differently. Outstanding symptoms are listed below to help you to detect this problem quickly. Including:

Symptoms Of Hydraulic Lifters

Excessive preload can cause a drop in oil pressure and cylinder head distortion since an overheating phenomenon occurs in the internal engine.

This easily results in decreased qualified output and extreme contraction of engine components.

You can also hear some ticking sounds when your car is stuck in too much lifter preload, which will annoy you.

Symptoms Of Mechanical Lifters 

The lifter preload indicates the tension among relevant parts in the internal and street engines.

There is excessive tension, and the relevant components (mainly the lifter and pushrod) tend to accelerate wear on the lobes, valve train, stock pushrods, stock rockers, and the other parts.

This results in a noisy atmosphere in your car or even locking the engine quickly.

How To Check LS7 Lifter Preload Correctly 

genuine ls7 lifters

Following how to check the LS7 lifter preload is one good preparation for monitoring the quality of the standard lifter system.

Nevertheless, all suggestions below can be reasonable for particular cars’ engines; thus, you must check more information to have the best adaptation for this problem.

Step 1 – Remove All Spark Plugs And Check The Intake

You make sure that all spark plugs are removed from your to promote the process of checking lifter preload easily.

First, check the intake valve on the cylinder and put it on the base circle lobe diameter designed before.

You only do that by reasonably modifying the Comp pushrod length, which makes the engine turn until the exhaust pushrod rises to a higher level.

All will make the intake lobe lie in the right position.

Step 2 – Adjust Pushrod And Relevant Components

You should start adjusting the pushrod at the value (ex. 7.30 inches) below the standard value (7.40 inches)of the stock pushrod length.

Put the pushrod, mount the rocker, and strictly tighten the bolts to ensure a strong connection between the car rocker and the pushrod.

In some unexpected situations, while you have tightened these components, clearance between them still occurs. You must adjust or remove them constantly so that the clearance is zero.

Step 3 – Count the Revolutions

The value of each revolution is about 0.050 inches; thus, if there are ten turns from the initial length of 6.80 inches, you must add at least 0.500 inches to match the length of the pushrod.

At that time, the pushrod’s length must be attained by 7.30 inches. However, everyone should depend on the characteristics of the pushrod and rocker to have a reasonable modification.

Step 4 – Add A Reasonable Amount Of Lifter Preload

If you want to add 0.050 lifter preload, the targeted pushrod length is 7.35 inches, which can meet all demands relating to adding the amount of tension for your car.

You can easily seek this size for pushrods because most companies on the market are distributing these pushrods at different levels of prices. 

Step 5 – Check The Total System 

After completing the process of checking and adding LS7 lifter preload, you must install all parts removed from the initial stages to run the total system.

Once there are any mistakes, you must fix this problem immediately to maintain the running ability effectively.


What Is Wrong When Having Too Much Lifter Preload?

Too much lifter preload can lead to common problems, such as overheating the preload system, annoyed sounds, bad output releases, extreme contractions in the internal lifter body, and locking situations. All

What Should People Do To Prevent Excessive Lifter Preload?

The best solution that everyone can adopt for the excessive lifter preload is fixing the mistakes from both mechanical and hydraulic lifters in the car system.

Mistakes can be damaged lifter springs and arms, big clearance between pushrod and rockers, and wrong camshaft.

They are considered common faults contributing to the excessive preload phenomenon in cars.


LS7 lifter preload plays a significant role in promoting the quality of transmitting energy and air in the total system in the cars.

Note that having the right value of preload for the lifter is one of the most effective approaches to addressing the problems of lifters in a short time.

If you are not an experienced driver, you should take support from a professional team.

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