AFE Power Y-pipe with Gibson exhaust

[techno]

Well, just to add to the ever growing list of crap that breaks/fails/falls off/stops working etc on my 08 V6, the exhaust system fell off recently. The flange at the end of the y-pipe rusted away so I needed to replace everything from the manifolds back. I went with the AFE Power Ypipe and a Gibson exhaust with side exit.

The Pros:
TONS more power! I don't have any figures to prove anything, but the butt-dyno is very happy. If I was to guess, it feels like an extra 20hp over whatever it was before.
The idle sound is low and beefy and I really like it. Almost V8-ish. In fact several people have asked if I have a V8.

The cons:
The Ypipe is not formed perfectly and the outlet flange sits an inch or two higher than it should. I had to mod the Gibson a little to get everything fitting up ok.
It drones like a MFer between 1100 and 1800 rpm. This is where I spend a lot of time on my daily driving and after two weeks, I can't stand it any longer. I'm going to try a resonator tip to quiet it down, but otherwise, I might be selling this set up soon.

Since Gibson claim their product doesn't drone (which is prolly just sales talk), I'm wondering how much effect the removal of two catalytic converters has had on sound. Yes, the AFE ypipe removes two of the four cats.

 

[LOSTR4]

I note these instances of needing repairs as "Happy Accidents" as you can usually benefit more from aftermarket then the OE options...that being said, look into the Helmholtz resonators as they can cancel out the 110Hz drone you're experiencing...

 

[Terminator03]

I note these instances of needing repairs as "Happy Accidents" as you can usually benefit more from aftermarket then the OE options...that being said, look into the Helmholtz resonators as they can cancel out the 110Hz drone you're experiencing...

I like that “Happy Accidents” term! That’s actually how I ended up with the stainless TRD duals that I’m running. We were on a road trip towing a trailer when I heard this swooshing sound at highway speed. Turned out to be the tailpipe had sheared off the muffler. I used that to justify to my wife the “need” for a whole new system that I had wanted anyway, lol. Could have done stock replacement for half the cost, but I neglected to mention that...:bluejump:

OP, definitely try the resonator tip, as that may make it tolerable for you. I do believe that removing the CATs is what made it worse. My TRD system put a resonator the size of a small muffler at the very front of the system where it bolts to the main CAT. I’ve read of people cutting that out, then complaining of drone, so I opted to leave it in place figuring that Toyota must have tested and engineered it in for a reason. I couldn’t be happier with it. Because I have headers (with high flow CATs), it’s plenty throaty under acceleration, but tame at low rpms with no noticeable drone.

 

[techno]

The only Happy Accident I'm waiting for is the rear diff exploding so I can justify to my wife that I need an ARB airlocker! Fingers crossed, haha


Thanks for the replies guys, I'll update with what I come up with.

 

[Inv4drZm]

The only Happy Accident I'm waiting for is the rear diff exploding so I can justify to my wife that I need an ARB airlocker! Fingers crossed, haha


Thanks for the replies guys, I'll update with what I come up with.

Game over

marriage game over - Google Search

 

[Timberland]

Removing catalytic converters can absolutely cause drone and more noise overall. Might want to look into putting an actual resonator into the system somewhere rather than bolting on a tip.

 

[techno]

Last night I cut off the twin side outlets and bolted on an 11" resonator tip that points out directly towards the rear passenger side corner. It has cut out a noticeable amount of drone and overall quietened things down a little, so after one commute to work this morning, I'm definitely pleased with the result. Let's see how I feel after a week or two...