I too have problems with my QTP Headers and Y. Either the collectors on the headers or the y-pipe was 2-4 inches too short thus causing the section of pipe coming off the driver side header to bang, the crossover pipe from the driverside to basically rest against the tranny mount, not to mention that I had to grind away one of the tabs on the back of the tranny mount and needless to say I spent 4 days trying to get the Y to fit in there the best I could when low and behold I go over a speed bump (slowly I mind you)only to have the pipe catch on it and pull it off the driverside collector. I ended taking it up to a muffler shop to have cats installed cause the rasp was more than I could handle and while installing them they tried to adjust it better to clear the tranny mount... well it clears the trans mount but still hits under the driver's seat, hit's on the driveshaft tunnel (the flowmaster Y-collector) and hits the torque arm. I emailed QTP concerning the issues I was having and initially they offered help with whatever I may need. After a few more emails and no response I ended contacting mufflex concerning the Y-pipe since they are the ones that produce it for QTP and they informed me that since QTP switched out who was building the headers the QC went down the tubes. It's either the collectors are too short, point too far down, too far up or too far to the side. They said that quite a few people have come in there with problems like I'm having with the header and Y combination and that the Y-pipe mated perfectly to the headers that were built by whoever was building them before. I was also informed that that Y-pipe would mate perfectly to Hooker/Jet Hot headers since that's what it was originally intended for. I'm not trying to put down QTP and their product, the overall quality was great, I'm just providing what my recent experience has been and that with this new batch you'll most likely have some issues. I wish you luck to those who are still working on you're y-pipes, I just hope that I can have my issue resolved soon.

 

I bought my QTP's just before christmas last year. I have no fitment issues whatsoever. My before dyno was 321.6/336.1. My dyno after was 344.7/358.2. I have an 02 M6 car with stock everything except the 345HP package w/CME from SLP. I installed the LT and the Y w/cutout. Neither of those dyno's was with the cutout open. I actually lost about 1Hp with it open. The dyno dudes said that with it open the graph looks like there might be a little KR at about 5K RPM. My issues with the system is that the Y is in about 5 different pieces. Lots of leaks that won't completely go away. I was able to tweak the y so that it doesn't slap under hard acceleration. Also, the cutout leaks pretty bad so I took it off and capped it. Barry said that he would take a look at it for me if I sent it in. I just haven't got around to doing it yet. So the system netted me 23.1 HP/22.1 Tq. I do belive that I'm leaving a little on the table due to KR. I CAN definately feel a difference in not only the pull but the throttle response is far more crisp that before. So other than a few snags I one happy camper!

 

again, qtp went with a different vendor this summer.