Magnaflow cat-back exhaust install help!
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Teching In
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Magnaflow cat-back exhaust install help! I have a set of BBK long tube headers, BBK ORY and just ordered the Magnaflow 16723 catback system. I've removed the old exhaust. My question is the new Magnaflow mid-pipe supposed to slide INTO the BBK y-pipe? It appears that it wouldn't be able to go OVER the y-pipe.
Anyone have experience with this kit and headers/y-pipe?
Anyone have experience with this kit and headers/y-pipe?
TECH Senior Member
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From: Central Cal.
Being that the end of the midpipe is slotted, I think it should go OVER the end of the Y-pipe. You will find that in exhaust systems that in the direction of flow, pipes almost always go INTO the next pipe. The pic shows the midpipe going INTO over axle pipe, which goes INTO the muffler pipe, and the muffler empties INTO the tips.
The entry into the midpipe might be a bit smaller than the rest of it as the stock Y-pipe is actually 2-3/4" OD. The midpipe is 3" so the end that connects to the Y-pipe is sized to slip over a 2-3/4" pipe.
Does this help?
The entry into the midpipe might be a bit smaller than the rest of it as the stock Y-pipe is actually 2-3/4" OD. The midpipe is 3" so the end that connects to the Y-pipe is sized to slip over a 2-3/4" pipe.
Does this help?
Ok I see what you're referring to. Whenever I see a y-pipe, x-pipe, or h-pipe, people generally refer to that as the mid-pipe. G Atsma pretty much nailed it so I'll leave it there
Thread Starter
Teching In
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Being that the end of the midpipe is slotted, I think it should go OVER the end of the Y-pipe. You will find that in exhaust systems that in the direction of flow, pipes almost always go INTO the next pipe. The pic shows the midpipe going INTO over axle pipe, which goes INTO the muffler pipe, and the muffler empties INTO the tips.
The entry into the midpipe might be a bit smaller than the rest of it as the stock Y-pipe is actually 2-3/4" OD. The midpipe is 3" so the end that connects to the Y-pipe is sized to slip over a 2-3/4" pipe.
Does this help?
The entry into the midpipe might be a bit smaller than the rest of it as the stock Y-pipe is actually 2-3/4" OD. The midpipe is 3" so the end that connects to the Y-pipe is sized to slip over a 2-3/4" pipe.
Does this help?
My ORY pipe outlet measured about 2 3/4" inches diameter and so did this slotted end of the mid-pipe.
TECH Senior Member
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From: Central Cal.
OK. Your Y-pipe is 2-3/4" and the midpipe is 3", which is why it is necked down to a size BETWEEN these two measurements so the midpipe will still slip OVER the Y-pipe. At least that's what is supposed to happen. Have you tried to slip them together? The mouth of the midpipe should be 2-3/4 INSIDE diameter to fit over the 2-3/4 OUTSIDE diameter Y-pipe.
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Thread Starter
Teching In
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Yes I tried for about an hour to get it to slip over. I even tried bending the slots out a little to help and it still wasn't going on. Maybe I could try bending them out a little more but I'm not even sure the best way to bend them.
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Same issue when I bought the 15684 catback. I ended up putting and hammering a lot. If I were to do it over again, I would take it to a shop and have them build you a really nice y pipe with a good merge and have them fit it to your mid pipe. I'd do a 3" y into a 4" mid pipe, keep the muffler and dual 3" tail pipes. This will be optimal for power and it should be cheap. This is what I would do if you don't want a true dual and x pipe.
Magnaflow cat-back exhaust install help! i also had trouble getting my y pipe into the magnaflow system. went to harbor freight and bought their large muffler pipe expander. with that tool and some heat to soften the stainless i was able to stretch the pipe ever so slightly and get it to slip over the y.
I'm not familiar with the BBK ORY, but my Magnaflow mid-pipe was too long and a super tight fit on my Kooks y-pipe. I took it to an exhaust shop that was nice enough to cut and expand it for free, then I cut some new slots in it with a sawzall. But yes, it should slip over the y-pipe.
TECH Senior Member
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From: Central Cal.
I've had this exact same exhaust before and needed to get a reducer for the I pipe to fit with the y pipe because they're the same diameter. That was the easiest way to get them to work.
