So there I was sifting through hours of "search" results on the y-pipe mod and came across something interesting posted in a group deal file. It was stated there that aftermarket y-pipes will damage the engine in the long run. Is this statement true? I was considering the Y and B pipes with a tweaking of the stock muffler pipe like Larry had done on his 2k2... now I'm not sure.

Lonz

 

All I can think of is maybe on the old Cattman pipes, their flex section was failing and restricting flow. With Cattman's current version that has been fixed.

Besides that just about any aftermarket mod runs a risk.

 

I don't see the logic? It seems to me that the Y-pipe only helps the exhaust to flow out better once the combustion is completed. How can the engine be damaged by it unless the Y-pipe is poorly designed?

 

I think you meant damage to the o2 sensor?

 

There could be damage to the o2 sensor(s) and also the engine is running different than it should be because the o2 sensors are giving the computer wrong signals. Since the exhaust is no longer ran through the pre-cats, the sensors think the engine is running rich, when in fact, it is running just fine. Since the computer is getting a 'too rich' reading, your engine might be running a little more lean than usual. If you are talking about a 2k2 though, the y-pipe out for it keeps the stock pre-cats in place anyways.

 

The 2k2's Y pipes leave the pre-cats installed unlike the 2k and 2k1.

 

How would a y-pipe damage anything? The locations of the upstream O2 sensors remain unchanged and thus the sensors monitor A/F ratio the same way. The downstream O2 sensor location may change depending on your setup, but even then, those sensors are only there to detect the presence of the emissions equipment. They are only used as a back up in measuring A/F ratio if your upstream sensors go bad.

 

what about damage to a 2K engine? I plan on keeping my car forever.

 

I guess if I get damage I'll find out the hard way. But I am not going to take these pipes off my car. It runs so good with them on. I think maybe even better now that the computer has had more time to learn. It really pulls hard when it reaches about 5000 rpm. With a loose torque conveter and traction this car would be well into the 13s the way it pulls so hard when it reaches peak torque. A loose converter would keep it in that peak torque range.

No way I'm taking these pipes off my car!

 

I think he's referring to the unequal length of the Y-pipe arms. Supposedly that's bad for your engine, but it hasn't been proven.

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