Any advantage with divorced turbo elbow?

Sketchy564

Sketchy564

Driver
im picking up a t25 with an aftermarket elbow already welded on, but it is just a straight through elbow, and not divided at the wastegate.

My current blown t25 has a divorced XS power elbow just like this attached to it (by copper nuts, not welds)
259546_DSC04819.JPG


i cant really find too much info on this online, but is there any real benefit to having the divorced elbow on a small turbo like this? Its supposed to allow for faster spooling, but will it be anything noticable? Im trying to debate if its even worth it to bother de-taching the elbow thats welded on to put my divorced elbow on

has anyone had experience with both on the same turbo and been able to notice a difference?
 
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How would the noise be different? Its not a screamer pipe, it just goes back into the elbow and countinues out through the rest of the exhaust. But i am curious why you say that

according to descriptions for any divided elbows, it "separates the wastegate and exhaust flow by adding a divider plate to reduce turbulence in the exhaust system"
or
"has a built in divider to organize exhaust wheel and wastegate flow"
 
Its said to add a little tq to your car, but on a t25 you are not going to tell a difference. If the welded one doesn't leak, rock that shit out.
 
so i might lose a little bit of botom/middle end power? Right now my stock with basic bolt on SR pulls pretty hard from about 4k til about 7.2k at 8psi. Not so much below or higher.

Compared to a stock n/a KA, I like how i have power up there, and i understand its only a 2 liter, but i hate how you dont feel shit in low end below 4k, and my turbo spools pretty slow under 4k as well.
 
Theoretically its supposed to reduce turbulence and streamline exhaust flow

Edit - i missed ur post where u had the same crap
 
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It should make boost before 4k with a t25. You should check that out while you're at it.
 
fc3sbmx said:
It should make boost before 4k with a t25. You should check that out while you're at it.
Click to expand...

mine makes boost before 4k, but not full boost (8psi, spikes at 9)

its different in every gear, 3rd gear it will hit 7psi before 4k, 2nd gear is like 5psi, 1st you cant really tell cause its too short, 5h takes forever, and 4th i didnt really pay attention on the drive home.

Im guessing its either i have a small boost leak, or the fact that the turbo is blown. But its just the seals that are blown, the shaft play is minimal

IThaJokaI said:
^ this, I have 12 psi on a t25 before 3k..
Click to expand...

What mods do you have engine wise? I plan on running this next t25 at 12psi. I have a walboro 255, front mount, full turbo back, and intake on an s13 black top. Will i be able to run 12psi safely? or should i play it safe and run 10 untill i get my wideband fixed?

When it used to work, and the car was first running on open wastegate (with the old shitty compression long block), it would hit 18-20psi with a healthy 11-12 on the gauge (AEM) before it would slowly start to lean twards the middle (14ish) after 5.5k, so im guessing i should be fine, but id rather not fuck this motor up.

Emeru said:
x2

i have 9psi before 3k, my turbo spools instantely !
Click to expand...
This is wierd, ive heard the s15 ball bearing gt28 will hit full boost under 3k, so i assumed it spools faster than a t25, but maybe my turbo is just shitty?

im wondering if this new turbo will spool any faster since its not blown... then again ill be going from the divided wastegate housing to an open design, which should technically make it spool a little slower...
 
You probably have an exhaust leak, close to the turbo.

My car has been on 12 psi for quite some time, it just has FMIC, exhaust, metal intake and br7re plugs.

And a t28 will spool by 3k, my t25 spools before it.
 
yeah i was talking to my friend today. he has an s14 sr with the t28 and he said he will hit full boost for him (11psi) under 3 grand. He has the mods i have, plus an exhaust manifold. The only difference is he has an SR tranny and i have a KA tranny, so his gears are a little bit taller than mine.


As far as the exhaust leak, theres only two possible ones i can think of. The first is on the actual manifold. The studs sticking out of the head to slide the manifold on and tighten nuts on, the back stud is broken, so there is no nut on that one. I used high temp RTV for the whole manifold and the rest of the nuts are on tight, but would that missing nut cause a leak?

A lot of people were telling me its fine, but i have a feeling its not, cause its on the outside and not the inside where there would be other nuts holding pressure around it, if that makes any sense


the other leak would be elbow to downpipe. My elbow doenst have studs on it, so to connect it to the downpipe, i used 3 bolts a little skinnier, with lock washers and a locking nuts, but two are missing the washers, and one is missing the nut and just has a regular nut, but i checked this about a week after i put the down pipe on when i swapped the engine and it was still tight
 
Well...

It could be your manifold flange, look at the head and see if its black from exhaust.

It could be the downpipe.

Or it could be a small crack in your manifold, o2 housing, 4 bolt gasket, 5 bolt gasket. There is a lot of little places that leak, and you will never hear/see it. I suggest just replacing all studs/gaskets when you go to replace your turbo.
 
Will definatley check the back of the head today.. thats a good idea

I really doubt its the 4 bolt gasket, i put that on brand new, and that shit was THICK. I also put brand new locking tabs and the copper nuts from FR sport. The turbo has still never been taken off the manifold, Im guessing it should still be fine to re use, no?

The crack in the manifold, i guess thats possible but it doesnt seem likely on the strong ass stock manifold. How can i check to see if its cracked other than looking for it? cause most likely it would be tiny and not noticeable by eye.

I guess that could happen from getting raped by a speed bump at speed without a flex pipe? Ive ran over one before at a good 10mph on a shitty street where the bump wasnt painted and i wasnt paying attention


I want to replace the exhaust manifold gasket, but the one i have is multi layered metal. It wasnt new with this engine, but it was new with the last one. You think i should still change it out? Ill definatley get a new stud for the exhaust manifold, but my budget wont allow me to get all new studs and gaskets, even though i would love to.

The other thing is im wondering if im better off keeping my re-used multi layered metal exhaust manifold gasket, or buying a cheap shitty one like this
http://www.frsport.com/MRG-Copper-Exhaust-Manifold-Gasket-S13-S14-S15-SR20DET_p_8187.html
or this, which is probably a little better
http://www.frsport.com/Cometic-C4200-030-Exhaust-Manifold-Gasket-SR20DET_p_12519.html
 
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