RB presilencer: block off for split air pipe connection?
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RB presilencer: block off for split air pipe connection?
'86 na base/sport (no power steering, no abs), no engine mods, only exhaust and suspension
well, since I am doing the electric conversion for my 5th/6th ports on my na s4 and don't have a split air pipe anyway, would it be fine to just run a homemade block off plate for the connection for it on my racing beat presilencer? or should I cut the little snakey part on the presilencer off and weld the hole (thus making it like the s5 version of the rb presilencer)? I think a block off plate would be fine but the way the pipe is S shaped makes me kinda wonder if exhaust pressure would push past the plate a lot. I have it connected to the rb street header and custom 2.5" to a thrush muffler after the presilencer, single exit if that would matter. oh, and I got this presilencer for free so thats why I have one with the split air pipe connection and no split air pipe. someday I'll be turbo so didn't really want to try and find a split air pipe or another presilencer. just getting by...
well, since I am doing the electric conversion for my 5th/6th ports on my na s4 and don't have a split air pipe anyway, would it be fine to just run a homemade block off plate for the connection for it on my racing beat presilencer? or should I cut the little snakey part on the presilencer off and weld the hole (thus making it like the s5 version of the rb presilencer)? I think a block off plate would be fine but the way the pipe is S shaped makes me kinda wonder if exhaust pressure would push past the plate a lot. I have it connected to the rb street header and custom 2.5" to a thrush muffler after the presilencer, single exit if that would matter. oh, and I got this presilencer for free so thats why I have one with the split air pipe connection and no split air pipe. someday I'll be turbo so didn't really want to try and find a split air pipe or another presilencer. just getting by...
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I did that before.
Just made a little gasket,a little plate,2x10mm bolts and done.
If exhaust pressure blows that off then you are running 1000 hp.
Back pressure is minimal,about 3 pounds.
Just made a little gasket,a little plate,2x10mm bolts and done.
If exhaust pressure blows that off then you are running 1000 hp.
Back pressure is minimal,about 3 pounds.
#3
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thanks, I wasn't sure just because of the shape of the pipe and what not. I'm bone stock engine wise and decided to finally get my aux ports working since my turbo rebuild just seems to get farther and farther from completeion. story of being poor lol.
another question: do I need gaskets for the port actuators or can I just use make-a-gasket/rtv on them? they are probably not expensive but I already have rtv.
another question: do I need gaskets for the port actuators or can I just use make-a-gasket/rtv on them? they are probably not expensive but I already have rtv.
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a little paper gasket and 2 minutes and you can make them too,so your choice really.
If you use "The Right Stuff" (by permatex) it will set fast and that Goo won't go anywhere.
#6
Why are you going for an electric conversion? The RB/stock setup works perfectly well and there's nothing on it that can really fail. Also, it's already setup if you just throw on a split air pipe. I suppose you could gain like 2 hp by controlling when the ports open...
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KAL797
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