SuperNova Posted October 30, 2007 Share Posted October 30, 2007 So now that i've got the smog finally done and the Hatch is running great, i would like to add a little more, get up and go! You know, power. For being a EA81 with Spfi its pretty fun already, but a little bit more would be bad rump roast. So i was thinking of adding a cone air filter with a maf adapter but im having trouble figuring out exactly which one is the right one. Any Input or sites i can check out. Was also thinking about picking up a GL-10 muffler to get rid of some of the restriction. Quote Link to comment Share on other sites More sharing options...
daeron Posted October 30, 2007 Share Posted October 30, 2007 the stock air filter flows ample air for a 1.8L four cylinder. The stock replacement filter for the EA SPFI was the same cartridge used for an NA first gen 300ZX, 170 hp 3.0L V6. If it can flow that much air, it can flow enough for the little boxer. The limitations on airflow lie in the intake port sizes in the head (shared between two cylinders each) and the sheer size of the manifold and throttle body. You can inspect the matchup of the TB to the manifold, as well as the matchup of the components of the throttle body itself, and make sure all airflow surfaces and transitions are as clean as possible, and if you want to get into it take the manifold off and port match it to the head... and gain probably a little smoothness, a little power, and a little efficiency at all RPMs, but the gain would barely be noticeable. Its sort of an anal-retentive thing. Quote Link to comment Share on other sites More sharing options...
subyrally Posted October 30, 2007 Share Posted October 30, 2007 i doubt that you would find any gains with another muffler from a gl-10. if im not mistaken, they used the same muffler between all the car, turbo or not. you would be better off with an aftermarket muffler if you are looking for any kind of power gain, but there is only so much one can gain from exhaust in a non turbo car. Quote Link to comment Share on other sites More sharing options...
SuperNova Posted October 30, 2007 Author Share Posted October 30, 2007 i doubt that you would find any gains with another muffler from a gl-10. if im not mistaken, they used the same muffler between all the car, turbo or not. you would be better off with an aftermarket muffler if you are looking for any kind of power gain, but there is only so much one can gain from exhaust in a non turbo car. Well i read somewhere that the EA81 muffler is very restrictive, and that the turbo models muffler was alot less restrictive. And opening up the exhaust would give a bit more low end torque. And i would go aftermarket but i dont want the loud, ricer sound of most mufflers. Quote Link to comment Share on other sites More sharing options...
SuperNova Posted October 30, 2007 Author Share Posted October 30, 2007 the stock air filter flows ample air for a 1.8L four cylinder. The stock replacement filter for the EA SPFI was the same cartridge used for an NA first gen 300ZX, 170 hp 3.0L V6. If it can flow that much air, it can flow enough for the little boxer. The limitations on airflow lie in the intake port sizes in the head (shared between two cylinders each) and the sheer size of the manifold and throttle body. You can inspect the matchup of the TB to the manifold, as well as the matchup of the components of the throttle body itself, and make sure all airflow surfaces and transitions are as clean as possible, and if you want to get into it take the manifold off and port match it to the head... and gain probably a little smoothness, a little power, and a little efficiency at all RPMs, but the gain would barely be noticeable. Its sort of an anal-retentive thing. I understand that the airflow through the stock filter is more than enough for the motor. But its not the filter itself that im concerned with, its the air intake opening in the side of the airbox. The whole is maybe 3" long and 1 1/2" wide. Pretty small in my opinion. I figured opening up the exhaust and intake would help improve performance. And making the whole bigger is not an option since i do have to smog this car and i am in california. And i cant seem to find the same airbox in the junkyard. Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted October 30, 2007 Share Posted October 30, 2007 Well i read somewhere that the EA81 muffler is very restrictive, and that the turbo models muffler was alot less restrictive Turbo mufflers are the exact same mufflers as non-turbo ones. Even same part numbers. You're probably thinking of generic "Turbo" mufflers. They're regular mufflers that are designed to be less restrictive. Quote Link to comment Share on other sites More sharing options...
SuperNova Posted October 30, 2007 Author Share Posted October 30, 2007 Turbo mufflers are the exact same mufflers as non-turbo ones. Even same part numbers. You're probably thinking of generic "Turbo" mufflers. They're regular mufflers that are designed to be less restrictive. OK, so where can i find these "turbo" mufflers. I dont want loud. Maybe a little tone but thats about it. Quote Link to comment Share on other sites More sharing options...
hatchsub Posted October 30, 2007 Share Posted October 30, 2007 Dynomax super turbo muffler. Thats what i have on my sedan. Nice and quiet but with a little growl when you get on it. Flows very nice. As for more power you already got the SPFI swap. How is the rest of your exhaust? Do you need to do emissions? If not...dump the catalitic converter and straight pipe it or if you dont like that idea just get a generic high flow cat. Quote Link to comment Share on other sites More sharing options...
SuperNova Posted October 30, 2007 Author Share Posted October 30, 2007 Dynomax super turbo muffler. Thats what i have on my sedan. Nice and quiet but with a little growl when you get on it. Flows very nice. As for more power you already got the SPFI swap. How is the rest of your exhaust? Do you need to do emissions? If not...dump the catalitic converter and straight pipe it or if you dont like that idea just get a generic high flow cat. Cool, ill check it out. Is there a specific size or part #? Quote Link to comment Share on other sites More sharing options...
hatchsub Posted October 30, 2007 Share Posted October 30, 2007 If your going stock sized exhaust you want 1.75 inlet and outlet. The muffler body should be about 13 inches long if i remember right. And the inlet should be offcenter with a centered outlet. Quote Link to comment Share on other sites More sharing options...
Subaru_dude Posted October 30, 2007 Share Posted October 30, 2007 The whole is maybe 3" long and 1 1/2" wide. Pretty small in my opinion. I figured opening up the exhaust and intake would help improve performance. And making the whole bigger is not an option since i do have to smog this car and i am in california. How small is the hole that's bringing air into the filter box itself? I know on EA82's it's extremely small and making an additional hole helps with performance slightly. Or at least I've been told... I didn't really notice any difference. Quote Link to comment Share on other sites More sharing options...
SuperNova Posted October 31, 2007 Author Share Posted October 31, 2007 How small is the hole that's bringing air into the filter box itself? I know on EA82's it's extremely small and making an additional hole helps with performance slightly. Or at least I've been told... I didn't really notice any difference. 3" x 1 1/2" or so, i got the SPFI from a EA82 Loyale. But i dont want to cut a hole in the airbox because i do have to smog the car in california. If i could find a replacement lower portion of the airbox that would be cool, but since the MAF adapter and cone element cost only about 25 bucks i figured if would be easier and would allow more air then just cutting a hole. And i could just swap out the airbox when smog comes around every 2 years. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted October 31, 2007 Share Posted October 31, 2007 The correct MAF adaptor is for a Nissan 200SX. I used one just because trying to fit the damn EA82 airbox in an EA81 bay is problematic. GD Quote Link to comment Share on other sites More sharing options...
SuperNova Posted October 31, 2007 Author Share Posted October 31, 2007 The correct MAF adaptor is for a Nissan 200SX. I used one just because trying to fit the damn EA82 airbox in an EA81 bay is problematic. GD 200SX, thats all i needed to know. Thanks! And the airbox fit no problem in my Hatch, i just want a little more now that i finally passed smog. Also looking into getting muffler. Quote Link to comment Share on other sites More sharing options...
daeron Posted October 31, 2007 Share Posted October 31, 2007 200SX, thats all i needed to know. Thanks! And the airbox fit no problem in my Hatch, i just want a little more now that i finally passed smog. Also looking into getting muffler. sorry to dicker, just wanted to make it clear. If I'd have known the answer, I would have told you. Quote Link to comment Share on other sites More sharing options...
subyrally Posted October 31, 2007 Share Posted October 31, 2007 if yo are looking for a maf adaptor,go to pepboys, they are like $15 for a universal one that will bolt right up to the subaru maf. i think its made by spectre or something like that/ Quote Link to comment Share on other sites More sharing options...
SuperNova Posted November 8, 2007 Author Share Posted November 8, 2007 So, i ordered the MAF adapter from ebay for the nissan and it was finally delivered today. I went down and bought a cone air filter from the auto parts store and put it all together. And Holy Crap, wouldn't you know it, it actually made a noticeable difference over the stock airbox. Some people said its not going to make a bit of difference, but a snappier throttle and a definate increase in low end torque makes me a believer. Cant wait to swap out the muffler next week. Quote Link to comment Share on other sites More sharing options...
SuperNova Posted November 8, 2007 Author Share Posted November 8, 2007 The correct MAF adaptor is for a Nissan 200SX. I used one just because trying to fit the damn EA82 airbox in an EA81 bay is problematic. GD So what did you do to mount the cone filter? Mine saggs and flexes the whole intake tube down til the filter touches the wheel well. Quote Link to comment Share on other sites More sharing options...
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