Okay what are the differences between the Down pipe and the test pipe?? Or is the test pipe just replace the cat like for bolt on and off for emission reason?? What are the differences between dp and tp? What is a downpipe anyways? When runin the turbo how are the piping size suppose to go. Like 2.5 - 3" from the turbo manifold to the cat all the way straight out the muffler?????? This is with no cat would it be from the turbo manifold all the way straihgt out through the muffler with 2.5-3" pipin? Thanks for the help.

 

Help please

 

Down pipe takes air from the turbo to the exhaust... sometimes there is a cat in the way.. u can remove that and put a test pipe... there are such things as offroad down pipes which go strait from the turbo all the way to the exhaust.. kinda like a test pipe attatched to a DP but they are just one piece..

 

A downpipe bolts up to the turbo. All turbo cars have downpipes. A test pipe is usually replaces the cat because its just a straight pipe that has no restrictions.

art

 

Cool thanks. So would it be good for me to run a 2.5 or 3" dp all the way to the exhaust? Damn i wish i can get rid of the cat since i'm in CA which sucks How loud is it runin a 2.5 or 3" dp all the way to my Apexi N1 with turbo without the silencer and the cat????? Would it be noticeable. I don't want to get harass by the po po. What size of pipin should i really go on a Drag III boostin at 7psi. 2.5"?? or 3"???? I know for sure goin turbo is best to lose the cat since its restrictive unless i get a high flow cat or hollow it out or something. But which is better a RT cat vs a dp or test pipe??? If I want to get a test pipe it needs to be welded to the dp of the turbo right and welded to the pipin of the Apexi N1?????? Thanks for the help guyz.

 

dude,

the downpipe is the pipe that connects the header, or in this case, the exhaust manifold to the cat. then the other end of the cat connects to the "catback" piping to the muffler. think of the cat as the restriction point on a free flowing exhaust.

at least have a 2.5 downpipe... and keep it consistent. if you get a free flow cat, it would help... but its always better to get a straight pipe or hollow out your cat. think of everything like a long pipe from the downpipe to the muffler. whutever is smaller in diameter or restrictive is going to reduce exhaust flow.

 

Thanks what i meant was would it be better to get a high flow cat like RT or Carsound vs a testpipe???? Would the testpipe need to be welded on or its bolt on to the dp? Thanks for the help.

 

Just hit a muffler shop to make you a test pipe and to have 2 flanges welded at each end that will fit in place of your cat and meet up with the dp and exhaust piping. about 60 bucks dude and your set. Peace


[Modified by boost killz, 1:12 PM 9/4/2001]

 

Hey boost killz,
when having my test pipe made, should i have it so it BOLTS to my 3" thermal and my Down pipe, or actually have it welded to both? i am thinking bolting would be better, so i am gonna need gaskets correct?

 

Yes you would and YES bolt...welding could be a prob for future purposes like puuting it back to stock.

 

cool thanks for the help Also do I need to look into any kind of material for the test pipe to be made? Stainless? or what? thanks agian.


[Modified by IgniteTeg, 2:12 PM 9/5/2001]