Stock Lower Intake Manifold Replacement

[Dillon]

I recently bought a brand new lower intake manifold that's all stock. It comes with a bunch of different O rings but i can't seem to find any videos or guides online on how to properly install all the little things such as those. Can anybody help me with that? I also bought the MFI upgrade that I'm going to be installing as well.

Edit: forgot to mention this is for a 350 vortec

 

[stutaeng]

Was it a Felpro kit? They usually have lower & upper intake gaskets, injector body o-ring, throttle body, valve covers gasket and fuel line o-rings:

https://shop.advanceautoparts.com/p...80793-P?searchTerm=intake manifold gasket set

Also has distributer gasket.

Just have it handy when you take it apart, you can't put them in the wrong place...

 

[Dillon]

I do have that Felpro kit as well but this is the Intake Manifold I ordered:

https://www.oreillyauto.com/detail/...wd?q=intake+manifold+-+vehicle+specific&pos=1

The o-rings I'm referring to are the several small ones that come with this kit.

 

[east302]

The ones in the upper right of your link...

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...are for the fuel lines. When I did mine, the MPFI already had the spacers inside it but I had ordered an o-ring kit as well. That looks similar to what I received. I didn’t use the majority of it. The two fuel lines did need new o-rings, just match the size of what was removed.

 

[Dillon]

The ones in the upper right of your link...

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...are for the fuel lines. When I did mine, the MPFI already had the spacers inside it but I had ordered an o-ring kit as well. That looks similar to what I received. I didn’t use the majority of it. The two fuel lines did need new o-rings, just match the size of what was removed.

So basically I only need to use the 2 fuel line o-rings and the rest are not needed? Also what is the little bracket that comes with all those o-rings for? Sorry about all these questions. It's my first time ever doing anything like this. I'm assuming I can go ahead and install the MPFI and everything else onto the intake before I install it on the motor?

 

[stutaeng]

On a unrelated observation, it looks like the Dorman Intake Manifold Gaskets are the OEM-type that are rubber or plastic only? I was under the impression the Felpro ones that I linked are better because they are laminated with a metal layer.

This website discusses the differences: https://troubleshootmyvehicle.com/gm/4.3L-5.0L-5.7L/coolant-leaking-from-intake-manifold-gaskets

 

[east302]

Yes, you can install the injectors with the manifold on the bench. I bought my manifold from GM. I didn’t know that Dorman made one as well.

I don’t remember how many o-rings there were on the fuel lines. Definitely one on each line at the firewall connection but I don’t remember if there were any on the connection to the fuel injector housing.

Just disassemble carefully and you’ll spot them.

I don’t know what the brackets were for, but my guess is that it’s a “universal” kit. I still have one unopened and another bag of the same stuff somewhere.

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And in case you don’t have it, here are the installation procedures...

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[Dillon]

Yes, you can install the injectors with the manifold on the bench. I bought my manifold from GM. I didn’t know that Dorman made one as well.

I don’t remember how many o-rings there were on the fuel lines. Definitely one on each line at the firewall connection but I don’t remember if there were any on the connection to the fuel injector housing.

Just disassemble carefully and you’ll spot them.

I don’t know what the brackets were for, but my guess is that it’s a “universal” kit. I still have one unopened and another bag of the same stuff somewhere.

You must be registered for see images attach

And in case you don’t have it, here are the installation procedures...

You must be registered for see images attach

You must be registered for see images attach

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Thank you for all this info. It’s much appreciated.

 

[Dillon]

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Does it look like I put the injectors in to far?

 

[delta_p]

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Does it look like I put the injectors in to far?

Looks fine to me.

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