Just wondering how easy/ difficult it would be for an accomplished welder to modify my open t3 manifold, to turn it into a twin scroll..... That's if it is at all possible??

My thinking is, remove original flange,

Weld a divider where need in the collector (does it need to split pairing 1&4, and 2&3)

Weld a new Divided t3 flange to manifold...


Is this Do-able??

Nick

It **may** be possible - depending on the orientation of the primaries in the collector. If your looking at your manifold in the engine bay in front of you, then 1&4 should be on one side (say the left) and 2&3 will be on the (say) the right. The divider will go down the middle front-to-back.

Whether it could be done depends on the construction of the manifold; whether the primaries are grouped as above and how they're welded together in the collector.

Plus if you're doing things properly and going external wastegate, you will need two wastegates; one for each pair of primaries.

What's your view on successfully implementing a devided flange for a single wastegate?

And Nick D what housing/turbo are you planning to use?

Been looking at BORG Warner, s200x series..... Either 252 or 256 model.
Not the newer ball bearing EFR SERIES as they are mega money!
The ones I'm looking at DO have the extended tip compressor wheels thought so there 70mm (252) comp wheel can push 475ish bhp @ the 76mm (256) 550+....
Smallest turbine housing tho is Divided ar72, but the guy I've been in contact with about them assures me that a divided ar72 will spool quicker than an open ar63???
Not sure about this though??

Nick

Id say it would. You can get a .55 open housing for the s200 too. Spool up about 4500 Id say.

I got a near new Lancer Evo 6 twin scroll manifold and turbo for under 400 pounds, this is almost the same bolt pattern and port layout as the coupe.
Ill use a manifold flange as adapter. Usable boost from 3500-7500 rpm and potencial for 380-400 bhp. Huge possibilities for upgrades very affordable (500bhp hybrid upgrade for 400pounds) looks stock if your not a coupe guy

I have a full 1.7 bar at 3800 revs anyways, if I'm gonna upgrade turbo I wanna find a way to get same spool but to have 450+ bhp with it! I know I could prob have this using gtx range, but they are whey out of my price range!!
This is why I'm looking into twin scroll as an option!!

Nick

S200 cant be much cheaper if any. The Evo turbo would be the cheapest way to go

Yep, evo twinscroll with upgrade to FP Green (1100usd) yields This

To get the earlier spool up that's reputed to be a trait of twin scroll turbos it's suggested that a very short/compact exhaust manifold is the way to go. It's based on a theory thats referred to as pulse tuning. Not the type I have mentioned in the past that's aimed at utilising reflected pulses like is common on NA engines. The twin scroll type of pulse tuning (an OEM technique really) is looking to get the maximum from exhaust gases that have just left the cylinder but the merit is less as power rises. That's not to say the divided housings don't do good on performance builds as they do but the tailored package that gets the best low rpm performance is different to the tailored package that goes on to be a high powered success.

Totally agree, the twinscroll td05 16g gives a wery drivable engine tough.

The aim of a twin scroll manifold and turbo is to "space out" the exhaust pulses so they don't intefere with each other. If you use a single wastegate then the pairs of primaries (and hence the exhaust pulses)have to be linked up again, negating the effect of the twins scroll. You could keep the wastegate inlets separate right up to a few millimeters in front of the wastegate, but they still have to link up. It's not something I've had the opportunity to play with so I don't know how much you'd lose by linking them as close as possible to the wastegate, as opposed to keeping them completely separate with two wastegates.

Mitsubishi use a single internal wastegate on the Evo turbos. I don't see a problem trying to replicate that with an external so long as the wastegate seals each side from each other, easier said than done. Once the wastegate opens it makes no difference of course.

But with the single internal, isn't that because it's on the exhaust discharge?

I'm not sure what you mean Begbie but after searching the ends of the earth for a picture I found this

You'd probably have trouble making the divider meet the wastegate poppet valve the way the divider meets that internal wastegate penny in the picture so that it sealed fully. without propping the valve open.

That will teach me for not looking at the google images correctly I was under the impression that the penny valve was only coming from one of the divided parts of the housing.

...Having said that, I just Google Image'd "twin scroll single wastgate" and got several images showing just that, so I guess it must be doable! How much of a compromise it would be to having two separate wastegates I don't know.

The twinscroll version on the evo 4-8 uses a internal dual Wastegate
This is a ported but stock housing

The WRC Focus has a single wastegate off a divided manifold, two feeds into one. It's a cracking piece of fabrication.