Need a part number

[YYC-SIERRA]

Does anyone have a part number for the insulator from a 6.2 L86 intake manifold.

 

The rubber insert to help reduce noise. 

 

My new L86 manifold I ordered from rockauto didn't include this noise insulator. Do the L86 even have them?

 

My L83 manifold I replaced definitely had one. 

 

(Picture for reference but not sure if it's an L86)

[YYC-SIERRA]

I have an S&B CAI paired with the L86 throttle body & manifold upgrade...plus a stage 2 BTR cam. 

 

At below 2000rpm in 5th or 6th on the highway, the intake noise is egregious when going up any incline. Really raspy, vibrates my overhead plastic panel, sounds like its lugging.....but the actual power output is fine.

 

I'm hoping by adding this missing insulator, it'll reduce the noise. Above 2000rpm in 4th, 3rd. 2nd it sounds amazing!

Edited April 5, 2024 by YYC-SIERRA

[jrmcswain]

This weekend I will look at the stuff Hennessey took off my truck. I'll let you know if it had an insulator.

[jrmcswain]

In my box of parts, I find no insulator. This is off a 2017 with 6.2L I bought new. I have the intake, cam,lifters and an aerodynamic shield from the bottom probably due to aftermarket cat back exhaust.

[YYC-SIERRA]

3 hours ago, jrmcswain said:

In my box of parts, I find no insulator. This is off a 2017 with 6.2L I bought new. I have the intake, cam,lifters and an aerodynamic shield from the bottom probably due to aftermarket cat back exhaust.

 

Thanks very much for confirming that.

 

It appears there is no equivalent part from the L83 manifold. 

[YYC-SIERRA]

I found what I was looking for:

 

Fuel Pump Insulator - GM (12695634)

 

Question: Does anyone have first hand experience running their intake manifold with and without this rubber/foam insulator? How much difference does it make to the sound?