mountaingoatgruff Posted February 8, 2008 Share Posted February 8, 2008 what have you guys with spfi ea81's done with your air injection system? i'm doubtful of how much it actually helps emissions but i plan on hooking it up for my smog check and cuz i really do want to leave a cleaner atmosphere for my son - the biggest reason why i'm ditching my V8. i'm just wondering for future reference if anyone has noticed power or efficiency gains by eliminating the system. seems like the ea would breathe deeper without it, but i don't know how much air those reed valves really let by, with or without the control valves. Quote Link to comment Share on other sites More sharing options...
Skip Posted February 8, 2008 Share Posted February 8, 2008 The priciple behing the AIS is to provide enough 02 in the exhaust so that the cat can burn the unburned combustion by-products. You may fail a smog check that uses a tail pipe sniffer. Quote Link to comment Share on other sites More sharing options...
hatchsub Posted February 8, 2008 Share Posted February 8, 2008 what have you guys with spfi ea81's done with your air injection system? i'm doubtful of how much it actually helps emissions but i plan on hooking it up for my smog check and cuz i really do want to leave a cleaner atmosphere for my son - the biggest reason why i'm ditching my V8. i'm just wondering for future reference if anyone has noticed power or efficiency gains by eliminating the system. seems like the ea would breathe deeper without it, but i don't know how much air those reed valves really let by, with or without the control valves. The reason i eliminated it was it was backfeeding into the carb and gumming everything up. Its really more trouble than its worth and to be honest i do think if everything else on your car is up to snuff and working well that you can pass emissions without the air junk. Quote Link to comment Share on other sites More sharing options...
Skip Posted February 8, 2008 Share Posted February 8, 2008 hatchsub's reed valves are toast common problem Some older models let chunks of plastic get into the carb throat and hold the thottle plate open (yea, happened to me) If you have a visual inspection will they miss it? You could believe Hatchsub and try to pass or believe the Subaru engineers that designed the system. Your call. Quote Link to comment Share on other sites More sharing options...
mountaingoatgruff Posted February 8, 2008 Author Share Posted February 8, 2008 like i said, i'll be hooking the system up and i'm just asking about the potential effects of eliminating the system. i will be sure that i do everything i can to pass smog legitimately (aside from the fact that the whole spfi thing is kinda illegal), including utilizing the air injection system. let's suppose the engine and all of it's systems/components are operating as intended. i would just like to know if there is a noticeable difference in the way the engine operates if the air injection system is eliminated. is it more powerful or does it use less fuel? Quote Link to comment Share on other sites More sharing options...
Gloyale Posted February 8, 2008 Share Posted February 8, 2008 Wait, you converted to SPFI. Plug the ports on the head and ditch it. Quote Link to comment Share on other sites More sharing options...
hatchsub Posted February 8, 2008 Share Posted February 8, 2008 let's suppose the engine and all of it's systems/components are operating as intended. i would just like to know if there is a noticeable difference in the way the engine operates if the air injection system is eliminated. is it more powerful or does it use less fuel? No difference in the way the car performs. Just doesnt gum up the carb if your reed valves are shot like mine were. And yea Skip i dont need to pass emissions and a lot of my emissions junk wasnt working well so its all been ditched in favor of good old none smog carb. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted February 9, 2008 Share Posted February 9, 2008 Ok.... 1. The SPFI doesn't use AIS. It was only on carbed EA82's. You should not require it as the SPFI is not setup for it anyway. 2. The type of catalytic converter makes a difference here. The SPFI's cat was a different type than that used on the carbs and does not reuire the additional oxygen. Didn't you say you already added a new cat? 3. I have passed OR emissions with the AIS disabled. I've run the same engine through with it working, and with it disabled. The emissions did go up, but by so small a percentage that it wasn't even worth having it. 4. Most of the flunkies looking for smog "pumps" or AIS type systems are looking for an auxilllery input to the cat. Most have a seperate hose that feeds the O2 into the cat from the smog pump, etc. I have actually had the morons at the testing station mark N/A next to the check-off item pertaining to the air injection system because they didn't understand that the EA81 injects right under the heads. So chances are they will think it never had one anyway - even if you leave it on. The ways of older Subaru's are seldom understood by the layperson. 5. You can leave it in place and block the reed valves at the pipe with a quarter. On the vehicles that I haven't welded the bung's up for the pipe that's what I have done. GD Quote Link to comment Share on other sites More sharing options...
mountaingoatgruff Posted February 9, 2008 Author Share Posted February 9, 2008 so maybe i will eliminate the system. i've added a new cat and i don't anticipate problems with smog due to my actual emmisions quality. the problems i would expect, if any, center around the fact that my 84 car has a vac diagram under the hood that shows a carb and other things i obviously don't have any more and my muffler has rust pinholes. i'm planning on finding a good aftermarket muffler for it, but i want to wait till cash isn't so tight so hopefully i can squeak that by too. any suggestions on a good low restriction muffler that'll give me that low throb without whining at mid/high rpm's? i HATE glasspacks and the trademark rice rocket sound. i wonder what a mild 2 1/4" flomaster or dynomax would be like under there... the test techs around here don't ask questions. if the tech notices i have efi when it should be carb'ed he'll likely fail me on the spot and sent me to a ref who will then inspect my vehicle. if this happens the ref will be checking to see that my smog equipment is present and functional. i don't know whether they'll expect all available smog reducing components to be working or just those that are part of the spfi system but this is cali and to predict a state official's behavior you just pick the most retarded possibility! couldn't i just block the ports on the undersides of the heads with a bolt and a copper washer or is there something else (that wont require removing the heads) that will be effective to plug them? if it has to be inspected and the ref doesn't see the parts hanging off back there they'll probably be less likely to expect them to be functional so i'd prefer to remove the pipes and valves if i'm not using them. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted February 9, 2008 Share Posted February 9, 2008 Well - if it goes to inspection and they are inspecting it as if the engine was an SPFI then they won't be looking for it at all as the SPFI never had it. Blocking the ports... The thread is large, and metric. Good luck finding a bolt. What I do is cut the end off the pipe - threaded portion and the flared pipe end itself. Then I weld the threaded plug solid on the backside using an approrpraitely sized washer as filler. Grind it smooth and then screw it in with the flared pipe end to seal it. Paint it to avoid rust to the welds. Looks just like a bolt but has the flare to seal it properly. GD Quote Link to comment Share on other sites More sharing options...
WoodsWagon Posted February 10, 2008 Share Posted February 10, 2008 I don't think this has been pointed out yet, but if you have converted to SPFI, you MUST block off the AIS. The SPFI uses the O2 sensor to adjust the fuel trim. With the AIS system operational, the computer will always get a lean reading from the O2 sensor and run wicked rich all the time. Sucky gas milage and higher emmisions will result. Quote Link to comment Share on other sites More sharing options...
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