i reluctantly let a shop put on my warpspeed y pipe today. everything sounded good when i started it up and drove away. when i got home i wanted to feel the power and i noticed a clunking for a few seconds after i jumped on the gas while accelerating and then it would go away. i called them back and they said they installed everything right. i looked under and i dont think i see the hanger attached at all??? not sure if that would be the cause of this issue but it sounds like it could be imo. any suggestions? am i looking in the right spot for the hanger?

That part is your hanger alright, though I don't remember mine hanging so low.
Try to narrow down where in the car the sound is coming from, such as passenger side, driver side, front of the car, or rear of the car.
Also: If you can some how get under the car, try to check the install thoroughly. Doesn't hurt to get under the car (while it's cool) and check. Wiggle things and let us know how it goes.

Did u take a pic while it was on the lift? did u look at it? that pic doesnt help much, cant tell if its connected to the hangar

u need a hanger. THe y-pipe shoudl have had one at the flex section. Jus have them weld one on.

Also check all your heatshields. These tend to be the most common cause of exhaust rattles. Mine had come loose right before the rear beam; a hose clamp buttoned it down nicely. The heatshield over my precat was also hanging by a thread so I just pulled it off. These steps cured a lot of my stupid little rattling.

I had a my one of my computer clients who happens to be the manager of an exhaust shop weld a flange for me so I could bolt my WS ypipe to the rest of the exhaust and they didnt install the supplied hanger rather they friggin welded a piece to the y pipe and then to the rubber piece. I was soooo mad! Chances are that the exhaust is moving when you accelerate hard or possible a bad engine mount

The stock y-pipe has a hanger, why wouldnt u put one on the aftermarket???

I can't really tell but from that picture, they didn't use the supplied hanger that comes with the y pipe.

yeah i went back today and he said that he used the stock hanger from the oem y pipe. he put it up on the lift and tightened the heat shield a little and said i should be good to go. drive up the road and i have the same clunking if i accelerate hard on the start. if i dont then i dont get any noise. i took it back and he went for a drive with me and said that it is a bad design on the y pipe and that there is nothing i could do. he said that the air coming off the first downpipe is flattening out when it hits the second downpipe when accelerating hard and causing the noise. but a few oil changes ago nissan said my rear motor mount was going and that could be another possibility but i get no shaking of the motor at idle so i dont know