L98 EGR System
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
Re: L98 EGR System (geezel)
Don't know about in UT, but here in TX if you disable it you will fail the visual, and will definately fail the sniffer test. I'd leave it on, it isn't really going to gain you much hp by taking it off...
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 1,234
Likes: 5
From: Herriman UT
Re: L98 EGR System (Wheelman)
Further info - I'm talking about installing hooker #2149 headers that are provided with the EGR opening in the primary tube blocked off. I would install a non-functioning EGR tube so it would pass the visual.
Pro
Joined: Dec 2001
Posts: 715
Likes: 0
From: NYC NY
Re: L98 EGR System (geezel)
In CO I have never had a problem passing without EGR equip. and without precats even, but it's just because they don't do much of a visual inspection here. If you're car is in good tune I wouldn't think it would have much of a problem passing the rest of the test if UT is anything like CO as mine has always been able to pass. This is all in reference to Colorado standards though...
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Re: L98 EGR System (geezel)
Your test in SL county is different than mine in Davis. Mine gets passed. And my cat is gutless, too. The EGR affects the NOX, most, if you fail for that reason, you'll know why.
RACE ON!!!
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Le Mans Master
Joined: Mar 1999
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From: Fort Worth Texas
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Re: L98 EGR System (geezel)
in Texas, if the EGR is disabled, you'll have a hard time passing the NOx portion of the sniffer test.
NOx is caused by high combustion chamber temps (over 2500 degrees) and it's a deadly gas. EGR quenches the flame to keep the temps below this magical number. If you can imagine spraying a bottle of water into a charcoal grill and think of how it reduces the heat a bit, that's kind of like EGR in the engine. It doesn't kill the flame, just reduces the heat a bit.
This does cause a loss of power, but without EGR you would also have to be sure you don't have any detonation since your temps will rise in the combustion chamber.
Hope this helps you out....
NOx is caused by high combustion chamber temps (over 2500 degrees) and it's a deadly gas. EGR quenches the flame to keep the temps below this magical number. If you can imagine spraying a bottle of water into a charcoal grill and think of how it reduces the heat a bit, that's kind of like EGR in the engine. It doesn't kill the flame, just reduces the heat a bit.
This does cause a loss of power, but without EGR you would also have to be sure you don't have any detonation since your temps will rise in the combustion chamber.
Hope this helps you out....
Pro
Joined: Jan 2002
Posts: 657
Likes: 1
From: Some where, I'm still looking. Texas
Re: L98 EGR System (Marcho Polo)
in Texas, if the EGR is disabled, you'll have a hard time passing the NOx portion of the sniffer test.
NOx is caused by high combustion chamber temps (over 2500 degrees) and it's a deadly gas. EGR quenches the flame to keep the temps below this magical number. If you can imagine spraying a bottle of water into a charcoal grill and think of how it reduces the heat a bit, that's kind of like EGR in the engine. It doesn't kill the flame, just reduces the heat a bit.
This does cause a loss of power, but without EGR you would also have to be sure you don't have any detonation since your temps will rise in the combustion chamber.
Hope this helps you out....
NOx is caused by high combustion chamber temps (over 2500 degrees) and it's a deadly gas. EGR quenches the flame to keep the temps below this magical number. If you can imagine spraying a bottle of water into a charcoal grill and think of how it reduces the heat a bit, that's kind of like EGR in the engine. It doesn't kill the flame, just reduces the heat a bit.
This does cause a loss of power, but without EGR you would also have to be sure you don't have any detonation since your temps will rise in the combustion chamber.
Hope this helps you out....
Craig!!! It's about time you'vre come out of that rock you've been hiding under!
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Joined: Mar 1999
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From: Fort Worth Texas
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Former Moderator
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Re: L98 EGR System (gregfloyd)
You also have to consider the cam profile in this equation. Isn't it true that a cam with a lot of overlap will sort of provide a self induced egr effect?
yes, this is true. This is why the LT4 does not have EGR, because the cam profile does this.
