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What is this exhaust thing on my EA-81??


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OK, so what is this block and tube between the head and where the Y-Pipe attaches??

 

And secondly should it be on my 1986 Brat, or was another engine stuck in it at some point??

The parts guy at the dealership tells me that whatever it is shouldn't be there on an 86 Brat, thats why the studs I ordered and went to pick up weren't long enough??

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I have done the same thing many times myself. Your Y-pipe is from a different model. You need that spacer because your Y-pipe will not bolt up properly without it. The tube on the spacer is pinched off if I don't miss my bet.

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Air injection pumps air into the exhaust to promote continued burning of the exhaust gases, increasing exhaust temps, and leaving big ugly rusty things on the bottom of the exhaust ports. There is the vacuum style like yours that uses the exhaust flow to suck in air, or theres pump driven ones.

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That's the port for letting air from the Air Suction Valve (ASV) into the exhaust flow. Used in order to promote better converter function. There should be one on each side. MY 86 Brat has them.

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Yep, what everyone else said. I had a 82 GLF that I put another motor in, but I had no idea what it came out of(long story). I removed the blocks because I installed a Weber and didnt need all the emissions stuff. Get my drift?

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  • 4 weeks later...

Thanks for all the information, now...

 

I removed the blocks because I installed a Weber and didnt need all the emissions stuff. Get my drift?

So what happens if i take them off with the stock carb??

 

One on them is leaking where the small tube attaches. Will it affect the performance at all?

The only emissions testing that I have to worry about is a visual check, and if the parts guys at the dealership aren't sure if it should be there, I'm pretty sure the yocal doing the inspection isn't going to have a clue...

 

Where do those tubes go to at the other end?? What do I have to do there?

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Durring a visual check, they may find no AIS if you remove it - which is suspicous if you have a cat. At any rate, if you remove the spacer, your Y-pipe will not clear the engine cross-member. I would leave it all on there, as your catalytic converter will not work very well without at least one of the AIS valves operating. I block mine off at the valve with a quarter unless I'm driving to the DEQ as they cause backfireing on exhaust systems with small leaks.

 

The parts guys at the dealership are idiots. EA81's from 82 on all had AIS systems of some sort - either a single one on one side with nothing on the other, two AIS valves - one for each head, or in the case of the feedback carb models they had a single vacuum operated valve on the drivers side, and a blank spacer on the other side. The Y-pipe's for each type are different lengths where they mate with the head to accomidate no spacer's, a single spacer, or two spacers.

 

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Okay how about this one. I dont have a cat, put in custom y- pipe and 2" all the way back, I see how I should leave adapter on, but what about the asv stuff? should I block off the tube and start throwing things? or just leave it, I get a little cackle back through my dyna-flow muffler when shifting or backing of throttle.

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If you have no cat, then it should have been tossed with the old exhaust as it serves no purpose but to introduce burnable oxygen into your exhaust stream (thus the backfireing). Just block it off at the spacer with a quarter using the hacksawed end of the pipe. Keep the ASV's an the plastic silencers around in a shoe-box in case you or someone you know has the infamous ASV meltdown and needs one. The rest you can toss. You will need to block off the ASV intake ports on the air filter box as they by-pass the filter. Duct tape works well..... rubber caps would be good but are hard to find in that size.

 

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It did for me, yeah. That's pretty much why I have it disabled. Too much oxygen is being introduced into the exhaust, and unburnt fuel is mixing and then being ignited by the hot exhaust. The other way to stop it is to fix the rich mixture, but I've found that to be difficult with the Hitachi. The Hitachi's tend to run a lot more rich than they need to. The feedback Hitachi's did quite well when they were in tune.....

 

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