84SOOB Posted April 22, 2004 Share Posted April 22, 2004 I need to pass emissions soon with my '84 BRAT with the Weber. Should I worry about not having the EGR hooked up? I have been running it with the valve plugged with a vacuum cap. Thanks, Brian. Quote Link to comment Share on other sites More sharing options...
Qman Posted April 22, 2004 Share Posted April 22, 2004 Hey Brian, glad to see you're still about. If you have any concerns about passing emissions contact Ed and he'll let you know where to find the emissions guy in Seattle. He can usually get it adjusted to pass. He works out of his truck next door to the Georgetown emissions station. Ken Quote Link to comment Share on other sites More sharing options...
84SOOB Posted April 22, 2004 Author Share Posted April 22, 2004 Hey Ken, thanks for the quick response. Ed told me about that guy down on 4th Ave S when I ran into him at the PAP a couple of weeks ago. I kinda plan on going down there with some vacuum line and some spare sizes of idle and main jets that I have and keep my fingers crossed. I chucked my old Hitachi crap after I got through emmissions 2 yrs ago, with some tweaking I should be fine--Brian Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted April 22, 2004 Share Posted April 22, 2004 I would leave the EGR connected. The weber has ported vacuum for it, and all it does is reduce combustion chamber temps - which will save your exhaust valves, and your cat from being burned to a crisp. I suspect a bad EGR valve was the start of all the problems I had with my Brat - it took out the cat, and the AIS valve - which subsequently wasted my carb with molten plastic. And I think on my Weber'd wagon I have burnt the exhaust valves from running high RPM's with a non-functional EGR. She's started to smoke a bit under hard acceleration..... still has plenty of power so I'm guessing it's a valve issue. No biggie, since I'm building a better engine soon anyway. GD Quote Link to comment Share on other sites More sharing options...
Snowman Posted April 22, 2004 Share Posted April 22, 2004 I'm just wondering exactly how the EGR helps to reduce temps inside the combution chambers and protect the exhaust valves. On the ea82 intake manifold, it looks like it would only help with anything on the passenger side, since that's where it plumbs into the manifold. Am I missing something here? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted April 23, 2004 Share Posted April 23, 2004 Basically, it adds a small amount of exhaust gas to the intake stream (above 2k RPM's or so it begins to open) - the exhuast gas has a negligable amount of oxygen in it, and so cannot burn, and cannot therefore lean out the mixture like regular incomming air could. It maintains the same volume in the cylinders, and thus the same compression, but just with a less volatile mixture. Less stuff being burnt = lower combustion temps. It's a balancing act.... what's really funny is that the EGR removes oxygen durring the stage where the gas enters the combustion chamber, and the AIS puts the oxygen back in afterwards in order to assits the cat in converting the remaining HC's. As to placement on the EA82.... that I couldn't comment on. On the EA81, it's centrally located on the manifold. GD Quote Link to comment Share on other sites More sharing options...
Ratty2Austin Posted April 23, 2004 Share Posted April 23, 2004 just for the record, my wagon (and 2 other ea81 cars with and without webers) I have worked on, have passed fine without the EGR even hooked up. you can block it and still pass the worst of seattle area emissions, webere carb or hitachi. (FYI, my wagon is weber'ed, and it passed just fine) Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted April 23, 2004 Share Posted April 23, 2004 Yes - the EGR does not play a critical role in the emmissions equation for EA81's. You'll just burn the hell out of things if you don't use it. Actually - it does sort of - it acts as a measure to prevent destruction of what little emmissions equipment they have in the first place. There are two types used on EA81's - those with a connection for the anti-afterburn valve, and those without. The one without is better suited for use with a Weber, as you don't have to worry about that pesky valve, and trying to hook it up right with vacuum lines and such. All you need is ported vacuum to the valve, and your good. No need to block it off, or disable it. GD Quote Link to comment Share on other sites More sharing options...
edrach Posted April 23, 2004 Share Posted April 23, 2004 Rick, the next time I see you at the rallycross (May 30th ?), catch up with me and show me how you hooked up the EGR. I cleaned it and it is still there, but it is not hooked up to a vacuum line since I'm not sure where I would pull it from. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted April 23, 2004 Share Posted April 23, 2004 Hook it to the same thing your disty is hooked to. You can tee it off that line if you like. I'm not totally sure that both the ports on the front of the Weber are ported. I think one is under the throttle plate, and one is above. Basically, you want the one that's above the plate for both the disty, and the EGR. Despite some claims that have floated around here about using full-manifold vacuum for the advance, this is NOT a good idea. You will actually lose about 15 degrees of total advance this way, and your idle emmissions will go through the roof.... GD Quote Link to comment Share on other sites More sharing options...
edrach Posted April 23, 2004 Share Posted April 23, 2004 Rick, thanks for the info. I've always wanted to hook up the EGR again, but haven't looked into it far enough (or understood the vacuum system well enough) to do that. Thanks again. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted April 24, 2004 Share Posted April 24, 2004 That's no problem at all Ed. I have become very intimate with the vacuum system of late. Fixing vac leaks and such on my Brat.... I think the poor thing was built on a Monday. It's got so many problems that I work on it a couple times a week it seems. GD Quote Link to comment Share on other sites More sharing options...
edrach Posted April 24, 2004 Share Posted April 24, 2004 My Brat is currently waiting for some major engine work. Until now it's been exceedingly reliable but it's developed a massive head gasket leak (losing water out the exhaust). I'm wondering if the higher combustion temps might have had something to do with that since I've never seen it overheat. Of course high mileage could have something to do with it also. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted April 24, 2004 Share Posted April 24, 2004 And interesting supposition - and I would tend to agree that this is certainly possible. Especially if the HG was almost gone anyway. Might have pushed it over the edge. GD Quote Link to comment Share on other sites More sharing options...
subestyle18 Posted April 25, 2004 Share Posted April 25, 2004 So this proves that people have passed washingtons emissions with a weber. That is good to know, last time i asked people had been told it would pass but had not gone through yet. I am looking to get a new carb and was going to get a stock one just to pass and get the weber later. But Now i know, so i will just get the weber. david Quote Link to comment Share on other sites More sharing options...
84SOOB Posted April 27, 2004 Author Share Posted April 27, 2004 WooHoo!!! I passed emissions on Friday with flying colors. Didn't bother to hook up the EGR. Just a new cap and rotor, air filter, reset the Weber to "lean best idle" by ear like you're supposed to.--Brian Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted April 27, 2004 Share Posted April 27, 2004 As has been stated in here several times, the EGR doesn't play a huge part in emmissions on the EA81. It's primary job is to reduce combustion temps. Reducing combustion temps helps a whole host of things, only one of which is reduction of NOX emissions (and even then, only by around 15-20%). GD Quote Link to comment Share on other sites More sharing options...
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