EGR question

[bhw33191]

I got an LM1 350 to swap into my caprice. I was cleaning it up and noticed it doesn't have an EGR unlike my 305. What does the EGR do? Is it just emissions garbage?

[silicon212]

Exhaust Gas Recirculation. It cuts down on NOx emissions by recirculating some exhaust gas into the engine to lower peak combustion chambers.

NOx mixes with hydrocarbon emissions in a photochemical reaction (sunlight) and creates ground-level ozone. Remember, ozone while beneficial in our atmosphere is actually quite toxic.

[Blue Bowtie]

The other benefit of EGR is that in reducing combustion chamber temperatures you can often increase ignition timing slightly and produce a bit more power from every ounce of fuel.

[j cAT]

Originally Posted by bhw33191

I got an LM1 350 to swap into my caprice. I was cleaning it up and noticed it doesn't have an EGR unlike my 305. What does the EGR do? Is it just emissions garbage?

was this 350 a boat engine? with no EGR you will need 93 octane..
as mentioned the egr is open above idle to blend some exhaust gases into the combution chamber.. with this occuring the combustion chamber has less oxygen this then reduces the temperature..

this lower temp allows the use of 87 octane.the egr ports also help heat up the fuel being drawn into the engine, as this port is directly below the throttle plates of the carb..

with a boat engine this would not be needed because the cooling water would not get this into the high temp area as a land motor vehicle..

you have cold water flowing into the heads....not high temp coolant..

also the engine in the boat in under a constant high load condition..

[bhw33191]

Originally Posted by j cAT

was this 350 a boat engine? with no EGR you will need 93 octane..
as mentioned the egr is open above idle to blend some exhaust gases into the combution chamber.. with this occuring the combustion chamber has less oxygen this then reduces the temperature..

this lower temp allows the use of 87 octane.the egr ports also help heat up the fuel being drawn into the engine, as this port is directly below the throttle plates of the carb..

with a boat engine this would not be needed because the cooling water would not get this into the high temp area as a land motor vehicle..

you have cold water flowing into the heads....not high temp coolant..

also the engine in the boat in under a constant high load condition..

No not a boat engine. From what i've heard the LM1 is the typical car 350, but the guy i got it from said its the truck version, if there is such a thing? He bought it straight from a Chevy dealer and used it in his CK Blazer so i'm positive its a practical engine and doesn't use 93 octane. I looked up the part number on this engine (10067353). It is a car and light truck replacement. So maybe the guy had no knowledge of the need for an EGR and never put it on? If it turns into a problem i can always just install one later. But the thing is, I've heard something called an "EGR delete" before. I'd assume one would only "delete" the EGR to gain HP right?..I'm guessing thats only used in high performance situations correct? So yeah, maybe i'll have to install one later or use the one from my 305

[j cAT]

Originally Posted by bhw33191

No not a boat engine. From what i've heard the LM1 is the typical car 350, but the guy i got it from said its the truck version, if there is such a thing? He bought it straight from a Chevy dealer and used it in his CK Blazer so i'm positive its a practical engine and doesn't use 93 octane. I looked up the part number on this engine (10067353). It is a car and light truck replacement. So maybe the guy had no knowledge of the need for an EGR and never put it on? If it turns into a problem i can always just install one later. But the thing is, I've heard something called an "EGR delete" before. I'd assume one would only "delete" the EGR to gain HP right?..I'm guessing thats only used in high performance situations correct? So yeah, maybe i'll have to install one later or use the one from my 305

removing the EGR is not going to increase power..I never heard of an egr delete in a passenger vehicle..you will need 93 octane with no egr...because it will have pre-ignition [ping like hell]

call the boat yards near your you and tell them what you got for an engine ...this is used as the prefered boat engine...ask them about how the egr is missing see what they say.