ok, so I am getting ready to piece together a TBE system for my car....finally....and I have decided on the Perrin cat back.....but my question lies in the DP's.

what are the advantages/disadvantages (if any) of having a DP with a Separate down tube for the wastegate gasses (Perrin DP), vs. a DP with a bellmouth such as the Helix DP?

any info anyone can provide would be great and opinions are welcome.

Thanks in advance.

-Ted

 

http://forums.nasioc.com/forums/show...hreadid=445812

see if this will help.

 

I always think that a bellmouth is the best way to go, full non-tubed air all in one place going out the same in the other. But that's just my opinion, there are all kinds of theories. I think a 3" (don't kill me you 2.5 inchers) is best with no cats of course. But there are always other opinions.

 

Thanks for the link ScoobyBoy.....it actually did help out alot

after reading the aforementioned link, I have come to agree with this theory (iLoqin). It seems as though the divorced style, even with the "splitter" will still cause some turbulence in the gasses exiting the turbo, especially the wastegate. Although the splitter is designed to keep the exhaust gasses separated, the tube for the WG gasses does not open wide enough for the exiting gas to flow smoothly into the separate downtube due to the large area opening on the turbo vs. the small tube that the gasses must get forced through. So the exiting WG gas gets dumped into the open "void" in the back of the turbo then must find its way into the tube. Therefore the exiting WG gas is still hitting the flat surface of the flange around the smaller WG downtube.

Whereas the bellmouth style is pretty much just an extention of the "void" on the back of the turbo since it is pretty much the same size and shape as the exhaust side of the turbo, so when the exhaust/WG gasses are dumped outta the turbo it is like its pushed directly into the DP because there are not any areas of the Flange exposed directly in the line of the exhaust flow , to create turbulence.

Wow, I think I just wrote a book...LOL, writing it out like this helps me to better understand how it works.

-Ted