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Old 04-27-2004, 12:41 AM   #1
bigcarguy
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EGR valve- really neccessary?

Ok, the carb on my 81 is now shot(yeah, even though I've only had it for 5 days). So I figure since it's gonna have to be replaced anyway, I could go ahead and put an aftermarket intake on it, too. I have a 72 with an Edelbrock carb and intake on it that I could use, but the intake isn't set up to use the EGR. So I was wondering if that thing is really even neccessary for the truck to run. I'm not worried about emissions testing because my county doesn't have the emissions test plus the guy that had it before me already ripped off the Cat so I wouldn't pass anyway. Can I use the intake without using the EGR?
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Old 04-27-2004, 01:06 AM   #2
bpmcgee
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Yes, you can use an EGR blockoff plate, but my understanding is that the EGR is one of those devices which helps emissions and really doesn't cost you any performance.

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Old 04-27-2004, 01:20 AM   #3
Joey-D
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I hate to change the subject, but I am trying to find out how the egr valve is hooked up. I need it to pass emissions and my truck came with a egr block off plate. I need it to pass the visual inspection plus it will help me pass the actual test. I just ordered a EGR valve, now I just need to know how to run it. PLease help!
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Old 04-27-2004, 10:52 AM   #4
mhicks
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EGR

I took mine off a while back and built a plate to take its place. I don't seem to be having any problems. I have a '73 with a 350.
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Old 04-27-2004, 10:59 AM   #5
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EGR comes on above 1200 RPM. It can help lower detonation under certain loads just before the engine is lugging and needs to drop a gear. Under full throttle it's usualy off because intake vacuum drops to a point where it can't hold the EGR open.

As for the question on where to hook a EGR up. It needs to be on a timed port. Where that is depends on the the carb. On a Quad that is usualy the driverside of the carb mid way up the front and the same internal porting as the Vac advance gets. If you have a Vac gage hook it up and find a port that is pulling about 12hg at steady cruise above 1200 RPM and off at Idle.

Some GM have a solonoide that also controls EGR. Look under your hood and on the core suport and see if the emmisions info sticker is still there it usualy has the Vacuum routing info.
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Old 04-27-2004, 06:12 PM   #6
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I have a holley 600cfm and as far as the radiator support, the front clip is off a 91 burb with tbi.
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