not sure if this is the right place but i'll take a shot.

i have a 05 evo viii and installed my 3" tbe sys w/ hi flo cat last week. Have had no problems at all w/ it for like a week. The other day it rained kind of hard and certain areas were flooded out but i avoided those roads. Anyways on the way to the house i notice a noise that sounds like i'm dragging something metallic under the car. I park the car thinking my pipes fell or some ish and check it out and everything is coshure. The noise occurs when i'm in 1-2 gear. Anyone know what this can be?

Does it cause a real bad vibrating noise in the car and will stop and go away if you stop the car and then start again? Does it depend on the rpms? Also do you have an intake?

does not cause a real bad vibration noise in the car. Only happens when i'm doing low speeds 10-25ish, goes away when i'm on the hwy. I do not have an intake. Only mod i have is teh TBE sys. and i would say its rpm dependent btw 2k-3.5k

Mine does that too, though it will do it at highway speeds when the roads are very wet... The most plausable explanation that I was told is that with the reduced clearance of the 3" pipe, driving on wet roads can cause cold water to hit the pipe, cool one side and pull it against one of the driveshaft bearings for a period of time until the temp equalizes. What you hear is actually a rattle...

idk if thats the case. I never noticed it before but then again it hasnt rained like this for a long time. if its a rattle its the scarious rattle evar. seriously sounds like i'm dragging my pipes under me. Is there anything i can do to get rid of this. really not like the demon noise coming from my car esp while other ppl/cars are around.

I had my hi-flow cat actually come loose inside the enclosure and it sounded like that only at low speed. Ended up beating the thing out with a broom handle.

No rattle and now i have a home made test pipe!

Yeah I would have to agree with his response. I would also say that it is the larger downpipe hitting the front support bar on your car. Look under your car and see if you can see any signs that the downpipe came in contact with the bar.

so you think it'll be the hi flo cat? i kind of think its coming from up front somewhere.

It is a VERY bad sounding noise...What I did and it seems to have worked is apply some high temp silicone RTV to the edge of the bearing "frame" where it was closest to the pipe. This seems to provide a cushion. Have not heard the noise since, but it has not rained much either..

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