Will divorced DP work on a stock turbo?

[bkaeser]

I have read that the stock turbo doesnt have an external wastegate and most of the DP used are bellmouth, but I dont know if I will be upgrading turbos and wastegates later. And Invidia DPs are mostly Divorced. So basically, Can an invidia divorced DP work on the stock turbo? Tried searching, no luck.

 

[Grinder34]

yes. divorced just means two tubes that join up later. bellmouth is one large collection chamber. The invidia divorced ones will work on a stock turbo. If you do upgrade to an EWG, they usually just dump to atmosphere under the car.

 

[bkaeser]

well if they both work and EWG dumps to atmosphere, what would be the benefit or downside to one over the other?

 

[Grinder34]

honestly, I think they're about the same. Some divorced designs could be slightly less restrictive and promote better airflow. But as long as its not the stock design, they're both MUCH better.

 

[bkaeser]

sounds good. Thanks for the info. Now I just have to decide if I want a catted on or not lol.

 

[Spamby]

Theoretically the divorced design, whether bell mouth or a twin tube (like Perrins) is supposed to decrease turbulence as the exhaust gases and wastegate gases meet as they exit the turbo. This is supposed to make the gases more free flowing.

As Grinder said, anything is better than the stock DP. When you see the factory DP, it is essentially a flat plate with one small hole for only the exhaust gases to move freely. This part is very restrictive of both exhaust and wastegate pulses.

I am using Invidia's catless DP with the splitter in the bellmouth. I have had no issues in the last 3-4 yrs.

I have heard that some have had issues with that splitter protruding too far into the turbo and hanging up the wastegate. They in turn have ground some of it off to facilitate fitment. I don't think the issue is common and wouldn't worry about it.

 

[bkaeser]

I just see that Invidia only makes Divorced Downpipes. And the Cobb one is too expensive and 2.5 at the end. I want a full 3" DP

 

[Spamby]

I wouldnt even bother with a divorced DP lol, HP gains are sooooo minimal that its not even worth the extra $$. just my .02

I don't see why divorced would be any better than bellmouth, because a divorced downpipe has got to be pretty damn special if it truly separates the wastegate from the exhaust path. Otherwise, you've got a half-assed plate trying to divide things and there wil be leaking and turbulence around the edges.

Very true. I figured that's why the Invidia piece has that protrusion into the turbo to help straighten the swirly mess. Whereas others, like the Perrin, just have the two holes with no ramp.
This is a debatable subject and one that I think both parties are correct.

OP. Don't get too hung up on divorced or not. Just get a good quality pipe - good welds and thick flanges.

 

[Z1107]

Talk to the vendors, I was looking for a new exhaust w/dp and I was quoted an excellent price by defined. Our other vendors are just as good.

 

[bkaeser]

You should prbably look again because i definitly have a non divorced invidia down pipe. You are looking in the wrong place dude

I should have specified, I have a 2011 sti. I found bellmouths for the older ones but even the invidia website didnt have bellmouth for this year.

 

[Bluedemon_II]

Jordan @Defined can hook you up. Also, I have never used a divorced wastegate dp. Not in any subaru that I had, not even possible in my genesis. The design is efficient at most but you wont get mad gains from running one. Back in the day, the term was used more as a marketing gimmick than anything else.

 

[IGOTASTi]

Jordan is no longer a Vendor here.

 

[Grinder34]

try posting a quote request here:

http://www.igotasti.com/vBforum/forumdisplay.php?288-Request-A-Price-Quote

the vendors should get back to you with good prices and options!

 

[bkaeser]

Ok, I am going to do that, thanks

 

[Vermont]

Personally I went with a El cheapo Megan racing catless bell mouth for about $250 new. Been on the car since 2009 and have yet to have a single problem with it. Heck at this point I am not even on the stock turbo any more and still nota worry. Don't get all hung up on one brand or another. Go with what fits your budget and needs best.

Pretty much all catless 3" down pipes do the same thing. They move gas away from the turbo in a hurry. On the stock snail you are not going to notice a difference between divorced and bell mouth.