sweethatch1866

My turbo manifold is t4 twin scroll with dual wastegates. I just picked up a sc6262 t4 turbo that is single scroll. I think the two will still work together if I plug off one wastegate ports. Anyone encounter this issue and have some in put????? Need help asap, I have a dyno appointment in two weeks.

Spooln4

Basically when each scroll of the manifold meet the open T4 the exhaust path will blend into the open T4 housing. This shouldn't be an issue but twin wastegates are probably overkill. Why not find a divided housing to take advantage of the twin scrolled manifold and improve spool?

sweethatch1866

thats my plan but if I get the power and spool time with out spending another $300+ I would be better off. Your thery makes since but my next question is weather or not it going to cause the turbo to serge and if I run it like that will it melt the center section of my manifold? I dint plan of parting the car out but if something happen it would make a $1000 manifold worth about $300.

Spooln4

Why not resell the 6262 and purchase a new one from a vendor including the divided turbine? I can get a billet 6265 for 900 shipped with divided turbine brand new off ebay.

Turbo surge is related generally to a very quick spooling turbo, I'm assuming the 6262 is going on a honda application so I don't think you have to worry about surge and running an open turbine housing would more hinder spool than improve it so I don't think this will be an issue. A ported/shroud compressor cover will relieve some pressure of the compressor wheel if surge is an issue. The only way you might "melt" hard steel is with a terrible tune or tons of Anti-lag which creates a very lean condition in the manifold. I've never heard of a divided manifold to open turbine causing this, the supra guys run setups like these all the time.

Fabrik8

No. Surge is caused by compressors that flow too much for the amount of air the engine can handle. It's about flow. Spool speed by itself has nothing to do with turbo surge.

If a turbo is spooled and CAN flow more air than the engine can handle at that point, surge can occur.
If a turbo is spooled and CAN'T flow more air than the engine can handle at that point, surge will not occur.

If you're getting surge, you haven't sized your turbo properly.


Anti-lag doesn't create a lean condition, anti-lag is actually burning fuel in the exhaust manifold because the ignition timing is severely retarded. That's why so much heat is created; the combustion event is moved somewhat outside the engine and into the exhaust.

sweethatch1866

The turbo has the s cover. I think im going to run it and see what happens. I made some calls and everyone says it will be fine. Im assuming there is no need in running the second wastegate because both runners are combining at the turbo housing, correct?

Spooln4

I meant in general most quick spooling turbo's are prone to surging, hence why most offer ported/shrouded compressor housings Ie GT30's /35rs equivalent and almost all larger garrets include them. Yes each application is different and will vary depending on the motor, I was trying to keep it short and sweet.

Whoops, forgot how dsmlink created anti-lag and I do remember now that the timing was adjustable and fuel enrichment was also an option. I do recall it pushing the combustion further out in the manifold which can cause wear and tear on the turbine blade and longevity of the center cartridge.

sohc_mshue

I would run both gates.