Many people do not have the faintest idea about the LS intake manifold torque sequence. If you are in the same boat, this article may come in handy.
I will present much information about the torque specs for different devices and the LS intake manifold’s installation. Let’s get started!
What Is The LS Intake Manifold?
The LS-based small-block engines are a combination of V8 along with V6 motor parts, which are designed and manufactured by the General Motors brand.
Regardless of a novice or seasoned driver, it’s best to explore the torque setting for its inlet manifold for latter installment or disassembly.
It is an automotive device responsible for distributing the fuel-to-air mixture to the cylinders.
More specifically, I will help you gain deeper insights into this engine’s bolts and firing orders, which provide powerful torque for the intake manifold and your car, in general, to operate smoothly.
What Are The LS Intake Manifold Torque Sequence & Specs?
The torque specs and sequence vary in different LS engines.
For example, the 5.3L uses 5 – 10 Nm of torque, while you have to apply 10 – 13 ft-lbs of torque to the aluminum intake manifold.
And the 6.0L needs 5, 10, and 30 Nm depending on the first, second, or final pass.
Here are the torque specifications for different inlet manifolds’ kinds that you should pay close attention to.
5.3 LS Intake Manifold Torque Sequence
The torque sequence is shown as follows:
- The first pass: 44-inch pounds or 5 Nm
- The second pass: 989-inch pounds or 10 Nm
- The sight shield bolt: 10 Nm (89-inch pounds)
- The inlet manifold sight shield retainer bolt: 5 Nm (44-inch pounds)
Aluminum Intake Manifold Torque Specs
10-13 ft-lbs is correct for an aluminum inlet manifold. Moreover, the torque should be specified for an aluminum manifold, which currently uses the LT-1 bolt assembly.
Suppose you have to install this manifold type and attach a carb to its outer surface; those bolt torques are quite low that its materials do not make any difference.
6.0 LS Intake Manifold Torque Specs
The 6.0 LS intake manifold’s tightening sequence is quite similar to that of the 5.3 LS device:
- The first pass: 5 Nm (44-inch pounds)
- The final pass: 10 Nm 989-inch pounds)
- The first sight shield bolt: 6.0L Engine – RPO LQ9 (measured in 89 inch pounds)
- The second sight shield bolt: RPO LQ4, 5.3L, and 4.8L (measured in 44 inch pounds)
- The inlet manifold sight shield retainer bolt: 5 Nm (44-inch pounds)
- The valve rocker arm bolts: 30 Nm
SBC Intake Manifold Torque Sequence
The SBC engines’ intake manifold bolts should be torqued in a sequence requiring two steps, measured in around 30 lb-ft.
To undertake this, I have tried to set up the pattern and rotate the wrench to 20, repeat this act twice before switching it to 30.
You could try this formula at home. Yet, be careful to avoid getting injuries and accidents.
How To Install The LS Intake Manifold?
Installation Prerequisites
Before you knuckle down to the installation procedure, you must meet the following requirements:
- Prepare necessary equipment, such as the torque wrench, plier, etc.
- Wear protective garments, like safety gloves or glasses, to protect yourself from harm.
- Ensure that the manifold is thoroughly cleaned and free from dirt and contaminants.
- Plug any unused vacuum ports
- The gaskets and seals should be put into place properly beforehand.
The Installation Process
- Step 1: Park your automobile carefully and shut all the engines down.
- Step 2: Clean the cylinder head’s surface with the assistance of a clean rag along with acetone.
- Step 3: Set the inlet manifold in place. Remember not to slide its surface around, as this act could dislocate the seal, resulting in a leakage problem.
- Step 4: Apply the locking compound on each threaded bolt.
- Step 5: Install the bolts tightly, and you should take close notice of the brackets as well.
- Step 6: Tighten the bolts meticulously by considering the make and model of your vehicle and manufacturer’s manual, including the sizes and specs.
- Step 7: Hook your electrical connections and vacuum lines up by using a torque wrench.
- Step 8: Place the throttle body and inlet tube into their original positions if you must take them out. This step is optional.
What Are The LS Torque Specs For Small Block Engines?
The SBC Brand
The SBC exhaust manifolds
The torque specifications should range from 20 to 25 lb-ft. If you don’t know which one to choose, it will be best to split the difference.
The SBC crank main caps and rod bolts
The pattern is quite straightforward. You should start from the central bolts before moving back and forth. Then, jump forwards and back to the outer two and the two inside.
The Ford Brand
The Ford Small Block Engines (289, 302, And 351)
There are numerous variations of Ford’s block engines. So, we just opt for three main engines, called the 289, 302, and 351.
The 289 engine torque specs are from 65 to 72 lb-ft, performed in two stages. The 302 vs 351 are also two-stepped, between the specs of 23 and 25 lb-ft.
The Ford Head Bolt
The 95-100 lb-ft torque sequence is applied to the Ford head bolt. Regarding the 351 engines, more torque should be added to the head bolts due to the development of horsepower and compression.
The Ford Exhaust Manifold
The exhaust manifold of a 281- and 302-engine car is torqued up to 25 lb-ft. But, this figure could increase to between 30 and 35 lb-ft in the 351 engines.
The Ford Bearing And Rod Caps
Given the 289- and 302-engine vehicles, the bearing and rod caps’ torque sequence should fall into the range of 40-45 lb-ft.
Yet, be careful with the 302 engine’s rod caps that must be torqued to 19-24 lb-ft.
The Mopar Brand
The Mopar Intake Manifold
In this section, we focus on the Mopar 318 and 360 engines. You need to undertake a total of two torquing steps to a maximum of 35 lb-ft.
The Mopar Head Bolts
The Mopar head bolts’ pattern should follow the three steps, torqued to the final 105 lb-ft.
The Mopar Rod Bolts
The torque sequence of the Mopar rod bolts should be adjusted to between 45 and 50 lb-ft.
The Mopar Crankshaft Bearing Caps
The bearing caps on the 318-engine vehicle should be torqued to 85-90 lb-ft, while the figure for the 360 engines stands at 85 lb-ft.
Frequently Asked Questions
How To Install The 5.3L Chevy Avalanche Intake Manifold Sequence?
Following is all-inclusive guidance on installing the 5.3L Chevy Avalanche inlet manifold.
- Step 1: Pull your car up. The challenge seems to be harsher if you are trying to stop a manual car, but everything can be solved.
- Step 2: Clean the 5.3L Chevy Avalanche intake manifold’s surface thoroughly by using steel wool.
- Step 3: Put the new gaskets on, using nuts and bolts to tighten them. If needed, you could cling to a specialized locking thread to ensure the best outcome.
- Step 4: Take close notice of the wiring network and surrounding vacuum lines before setting the manifold in place.
How To Remove The LS Intake Manifold?
- Step 1: Stop your car on the roadside or in the shadows.
- Step 2: Remove the wires by pulling the lid out.
- Step 3: Take out the cover, and disconnect the mouth sensor from the throttle body.
- Step 4: Get a rag to pull the fuse, steam lines, and other related engines. You must be careful when performing this process, as you could easily get harmed.
- Step 5: Remove the LS intake manifold. Check the wiring harness meticulously one more time before undertaking this step.
The Bottom Line
My article has provided much knowledge about the LS intake manifold torque sequence, coupled with torque specs for other brands’ engines and detailed guidelines on installing vs removing the inlet manifold.
Thanks for your genuine support, and have a nice day!