Removing the EGR?

[clinem03]

I have a mostly stock 76 302 with a stock intake manifold and ERG block between the intake manifold and carb. I assume the answer is no, but can I just bolt the carb to the intake manifold and remove the erg? I don't see a point to using it unless I have to with the 76 intake manifold and carbÂ…especially since I just painted my manifold. I don't live in a smog stateÂ…

 

[SevenT]

clinem03,

More with carbs can speak up, I am running Ford EFI.
You should use the plate as a carb spacer to eliminate heat soak in the carb and to stave off potential vapor lock. Block all of the ports and just use as a spacer.

Mike

 

[Rightpace]

If you're referring to the EGR ( exhaust gas recirculation) valve plate located under the carburetor, you will need to purchase a spacer plate so your carburetor linkage will clear the intake manifold.

 

[clinem03]

Thanks for the advice! Figured it needs to be there. I'll look for a spacer so I don't have a bunch of extra stuff on it.

 

[blubuckaroo]

What most do is slip a piece of .010” stainless shim stock between the EGR plate and valve. That effectively blocks the EGR, but now you have the timing, cam timing, and mixture to fix. It all works together. You're better off doing it all.

 

[clinem03]

Thanks Blubuckaroo - are you saying that if I add a spacer instead of the EGR it will affect my timing and mixture?

 

[blubuckaroo]

Thanks Blubuckaroo - are you saying that if I add a spacer instead of the EGR it will affect my timing and mixture?

What happens is the EGR system adds hot exhaust gas to the mixture to slow combustion. This hot exhaust is more squishy than cold air. It effectively reduces the compression ratio of the engine during certain vacuum conditions. This makes a more complete combustion and less hydrocarbons.

The camshafts in these EGR engines were made to run under these conditions.
Typically, when someone disables the EGR, they will end up with detonation and notice a ping under load. The normal response to this is to retard the timing. Now the engine runs poopy and stinky.

The proper fix for this is to replace the camshaft to one not designed for an EGR system.

 

[clinem03]

What happens is the EGR system adds hot exhaust gas to the mixture to slow combustion. This hot exhaust is more squishy than cold air. It effectively reduces the compression ratio of the engine during certain vacuum conditions. This makes a more complete combustion and less hydrocarbons.

The camshafts in these EGR engines were made to run under these conditions.
Typically, when someone disables the EGR, they will end up with detonation and notice a ping under load. The normal response to this is to retard the timing. Now the engine runs poopy and stinky.

The proper fix for this is to replace the camshaft to one not designed for an EGR system.

Wow, never knew removing the EGR would lead to so many downstream consequences! Outside of being bolted to the intake manifold nothing else was hooked up to the EGR when I bought the truck a few years ago. It had a “cap” on port on the back side of the EGR (see photo). Does all that stuff need to be hooked up for it to do it's job? Or does the plate and EGR between the manifold and carb do the trick?

 

[4WHLFUN]

Never heard that explanation before but it sounds good. You can dump everything in the photo, just be sure to plug the hole in the manifold that delivers exhaust gas to the underside of the plate. Alternatively, many manifold gasket sets come with a SS block off plate to block the center exhaust port between the head and the manifold. It's on the pass. Side head only. Sounds like it's too late for that. If you don't block the hole the exhaust gas will burn up a paper gasket. You should use a gasket with a steel shim similar to exhaust manifold gaskets. This is what the factory used (but with a hole for the gas passage). If anything I would think performance is enhanced even slightly as you're no longer introducing hot dirty air. The compression is so low on the engines that I'd be surprised if you experience detonation. Agree the fuel mixture and timing should be adjusted for optimal spark plug burn. Finally, be sure to cap the PVS port that supplied vaccum to the EGR valve, or disconnect altogether. This valve works on temperature and if connected to vacuum will open at temp. if still working. Use ported vacuum for your distributor advance.