tundrabrat Posted June 12, 2011 Share Posted June 12, 2011 On my EA81 do I need to run the charcoal canisters (that bolt between the heads and the exhaust manifold) in order to pass IM or can I pass without them? I'd like to ditch them if they aren't needed and won't effect performance. Link to comment Share on other sites More sharing options...
tundrabrat Posted June 13, 2011 Author Share Posted June 13, 2011 Lots of people looking, can anyone out there help?!?! I would like to have it on the road by next weekend. Link to comment Share on other sites More sharing options...
hatchsub Posted June 13, 2011 Share Posted June 13, 2011 You should be able to pass without them. They are not charcoal canisters those are the ASV valves (well the pipes up to the valves that is). Just takes air from the intake and pushes it into the exhaust to clean it up a bit. Doesnt really hurt performance but by this time many are backfeeding exhaust into the carb. Ive had it happen on all three of my subarus and have just gotten in the habbit of ditching them completely on every EA81 from now on. My method of ditching them is to unscrew the pipe at the bottom of the head...cut the pipe off and let it fall out of the fitting...stuff a quarter in the opening on the head and tighten the fitting back down on the quarter. Bye bye ASV pipe and ASV. Link to comment Share on other sites More sharing options...
tundrabrat Posted June 13, 2011 Author Share Posted June 13, 2011 (edited) You should be able to pass without them. They are not charcoal canisters those are the ASV valves (well the pipes up to the valves that is). Just takes air from the intake and pushes it into the exhaust to clean it up a bit. Doesnt really hurt performance but by this time many are backfeeding exhaust into the carb. Ive had it happen on all three of my subarus and have just gotten in the habbit of ditching them completely on every EA81 from now on. My method of ditching them is to unscrew the pipe at the bottom of the head...cut the pipe off and let it fall out of the fitting...stuff a quarter in the opening on the head and tighten the fitting back down on the quarter. Bye bye ASV pipe and ASV. Thanks! 3 follow-up questions... 1) Can I just completely remove them, since my exhaust manifold is already off? 2) Since it looks like this thing (see picture) plugs into the top of the ASV can I get rid of this as well? 3) If not how do I route it and what plugs into the blue tip? Edited June 13, 2011 by tundrabrat Link to comment Share on other sites More sharing options...
hatchsub Posted June 13, 2011 Share Posted June 13, 2011 Thanks! 3 follow-up questions... 1) Can I just completely remove them, since my exhaust manifold is already off? 2) Since it looks like this thing (see picture) plugs into the top of the ASV can I get rid of this as well? 3) If not how do I route it and what plugs into the blue tip? 1) I wouldnt just for the fact that its steel on an otherwise aluminum head. I used it as a place to tap the holes out for bigger exhaust studs so that i dont hae the problem of the exhaust studs stripping out of the soft aluminum. 2) Yup if you get rid of the pipe coming off the bottom of the head ditch everything else connected to it including that valve (which is the ASV) 3) Just make sure to plug up any ports that get opened on the air cleaner since if memory serves those things tie into it somehow. Link to comment Share on other sites More sharing options...
kanurys Posted June 14, 2011 Share Posted June 14, 2011 I thought the item in the picture with the blue hose fitting is an air injection valve actuated by manifold vacuum. It connects to somewhere near the EGR or puts air into the intake in certain situations. Most of them have a check ball that is rusted in place and they no longer work. Also, they are very expensive new. Many people remove them and suffer no negative effects. Just plug up the really big hose on the bottom. As far as the air suck valves (ASV's), there are several threads indicating that you can unbolt the metal pipe going into them and insert a $0.25 coin and reinstall. Correct me if I'm wrong but credit for that goes to GD. This is one option. I removed the entire system and plugged the heads which accomplishes the same thing but is much more clean looking and you have to make your own block off plates. I'm not sure, but it seems like a lot of this stuff was for a good emissions cause but after aging this long, now has a negative effect. If everything is working correctly and you have good ignition, timing, etc, then the only emissions thing to help you pass should be an EGR valve and a catalytic converter. The charcoal canister is another project when it comes to installing/removing, with it's own issues to deal with. Link to comment Share on other sites More sharing options...
tundrabrat Posted June 14, 2011 Author Share Posted June 14, 2011 I removed the entire system and plugged the heads which accomplishes the same thing but is much more clean looking and you have to make your own block off plates. . When I got the car the ASVs were off the car and in a box. It looks to me that they bolt directly against the head between the head and the ehaust manifold. Could you advise what on the head needs to be blocked. The charcoal canister is another project when it comes to installing/removing, with it's own issues to deal with. So can you give more detail? Thanks for the name of the valve, now I do some searches. Link to comment Share on other sites More sharing options...
kanurys Posted June 14, 2011 Share Posted June 14, 2011 I think the proper term for the valve with the blue port is the anti-after-burn valve. The ASVs should connect to metal pipes which run to the exhaust area on the heads, somewhere near where the exhaust manifold bolts to each head. They mount just to the rear of the heads, either on brackets that hang off the top rear of the head or some other bolt point. The charcoal canister has several lines. One from the carburetor to capture fuel vapors, one from a vacuum switch with other lines involved to actuate/open the canister which vents through another line back to the intake or manifold. There is another line from the fuel tank vent line, usually. Link to comment Share on other sites More sharing options...
Brock Samson Posted February 16, 2012 Share Posted February 16, 2012 Removal of the Nippondenso 420667100 084200-0260 anti afterburn valve (specific number from mine off my 1980 1st gen Brat) is recommended by experts. General Disorder being the main expert. If you have the Hitachi DCJ306-15, remove the AAB Valve prior to doing any carb tuning. Link to comment Share on other sites More sharing options...
6 Star Posted February 17, 2012 Share Posted February 17, 2012 Heres what I did with mine if you want a visual. Both heads with the extra junk still attatched: Took all of that crap off and the rubber hoses that went to them. Then plugged the spacers off the heads: Cleans up the engine bay a bit: Not sure if there are any differences between yours and mine, I didn't have to touch this afterburn valve thing that is being discussed. Link to comment Share on other sites More sharing options...
kanurys Posted February 17, 2012 Share Posted February 17, 2012 (edited) If you have the gumption, eliminate both the air suck valves and the anti after-burn valve. Your engine will run much better. I plugged the AAV with a big bolt in a shot piece of hose. Here is the block off plate I made on my heads. Though they're EA82 heads, it's the same concept. Edited February 17, 2012 by kanurys Link to comment Share on other sites More sharing options...
AKghandi Posted February 17, 2012 Share Posted February 17, 2012 (edited) With the I/m going away In the next month they are passing anything Edited February 17, 2012 by AKghandi Link to comment Share on other sites More sharing options...
6 Star Posted February 17, 2012 Share Posted February 17, 2012 What does removing the AAV do? Its there to prevent backfiring upon decceleration. So what benefits are there to removing it, besides creating more free space? Someone mentioned that the engine will run better, how? Link to comment Share on other sites More sharing options...
TomRhere Posted February 17, 2012 Share Posted February 17, 2012 I swapped an EA82 SPFI type EGR valve in place of the EA81 type when I removed the AAV from my BRAT's, as they don't have the fitting for the AAV hose connection. Link to comment Share on other sites More sharing options...
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