Downpipe/O2 housing

[TeeWX98GST]

Well, I was going to get an apexi downpipe and probably an ebay 2.5inch o2 housing with atmosphere dump. I currently have an apexi 3inch catback. So if i buy a 3inch apexi downpipe that will replace my catalytic converter right? And with the o2 dump housing and header i have + my catback should have full exhaust then. How much of an improvement is the atmospheric o2 dump over a stock o2 housing? And since i believe the apexi downpipe is 2.5 before the flex, then 3inch all the way back, it should bolt right up to the o2 housing with no problems right? Also, anyone have an idea on how much WHP gains i could see out of SS tubular header + o2 housing with dump + 3inch downpipe? (eliminating cat too.. i think)?

 

[Boost92awd]

It should tell you on the website if it will delete the cat or not. As for the atmostpheric o2 dump its going to be better with boost control. The hp gain over using an o2 dump compared to recirculating back to the exhaust will be minimal. As for the tubular manifold look to spend $400+ for a quality piece that is not going to crack. As for HP gain I would say anywhere between 20-40 hp for a full exhaust.

 

[hypnoticpimp]

So if i buy a 3inch apexi downpipe that will replace my catalytic converter right?

Yes

How much of an improvement is the atmospheric o2 dump over a stock o2 housing?

You might not notice it on the butt dyno bit i sure did

And since i believe the apexi downpipe is 2.5 before the flex, then 3inch all the way back, it should bolt right up to the o2 housing with no problems right?

For the most part yes, although some o2 housings flanges (where it connects to the downpipe) are at a diffrent angles than stock so you might have a prob... It's hit or miss...I have the megan recirculated o2 housing with an apexi downpipe and i needed two gaskets so the downpipe will mate perfectly with the o2 housing.

 

[TeeWX98GST]

What would you suggest between the N1 and GT downpipes from Apexi? They are both 2.5inches to 3inches after the flex, the only difference i really see besides a $50 cost difference is Aluminized Steel VS Stainless Steel, so pretty much just that SS would hold up better to the elements? I mean exhaust is exhaust..

 

[hypnoticpimp]

I personaly would go with the n-1 because rust isn't a problem where I live... If you live at a place where thay salt the roads in the winter, def. get ss

 

[TeeWX98GST]

I live in the Midwest, they spray the roads with some nasty chemicals somewhere around the lines of 2-3 times worse than salt for corrosion and rust, but my car sits in the garage all winter long, (as if i could drive it anyway with how low it is ) I'm not going to be driving it again until around may when its 80 degrees out and the salt/sand gets removed by the street sweepers. The chemicals remove the ice pretty good but sure make life suck for people who care about their cars

 

[Gstclipse69]

I wouldnt bother with a tubular mani right now/or at all. A 2g mani will flow what you can throw at it as of your mods now, and even well made tubular mani's are known to crack. They just look good

 

[rock0134]

teewx, I have the shit salt problems up here in wisconsin. My car is put away for at least another month What turbo are you running? You will notice a big difference with the 3" downpipe I really did, although I started to get boost creep after the install. I'm also planning on getting an ebay o2 housing with external dump. I am excited for spring.

 

[hypnoticpimp]

I live in the Midwest, they spray the roads with some nasty chemicals somewhere around the lines of 2-3 times worse than salt for corrosion and rust, but my car sits in the garage all winter long, (as if i could drive it anyway with how low it is ) I'm not going to be driving it again until around may when its 80 degrees out and the salt/sand gets removed by the street sweepers. The chemicals remove the ice pretty good but sure make life suck for people who care about their cars

Just try and get ss it's only a lil more and will last alot longer

 

[dsmconvict]

Why not look into the Megan DP. Can't beat 130 bucks...EXTREME PSI : Your #1 Source for In Stock Performance Parts - Megan Racing 3" Downpipe: Mitsubishi Eclipse 95-99 FWD

 

[rock0134]

that's true, exhaust is exhaust. You will hardly ever have to look at it again.. The megan racing downpipes are commonly used.

 

[TeeWX98GST]

teewx, I have the shit salt problems up here in wisconsin. My car is put away for at least another month What turbo are you running? You will notice a big difference with the 3" downpipe I really did, although I started to get boost creep after the install. I'm also planning on getting an ebay o2 housing with external dump. I am excited for spring.

I'm running the stock turbo right now, and as for the other comment about headers i already have a stainless steel header i got for cheap from a friend who totalled his car, and it was only on there for about 100 miles.