Geoff, Garrett has just released new .82 and 1.06 A/R divided T3 housings for GT3071R, GT3076R, and GT35R:

Garrett TS T3 Housings

 

cool to see - But OUCH at $400/hsg, thats half what the entire BW turbo costs!

maybe we will bring back the T3 twinscroll manifolds? The T4 twinscroll S200SX seems to be getting good reviews from an evo on lancer register, he says 2bar boost by 3800rpm

 

care to explain more in detail?

thanks

 

I wish Garrett would make a T4 1.06 or T4 1.10 housing for the 35R. IMO the ones we use now suck. I don't see a need for T3 in TS.

 

While I would like to agree, I don't know if that's really the case. Up until recently, you were stuck with 0.78 A/R T3 which I already mentioned would likely flow like a 0.47 A/R single scroll T3 and fully agree it is too small.

If you hunted around, you may have been able to pick up one of a handful of the T3 1.06 housings Drifto used. Have you tried the new 1.06A/R T3 divided housing though? I don't think the issue is T3 vs T4, I think it's just the tiny *** A/R that was previously the only option in T3 where now there are more options in the T3 divided frame setup.


FWIW, to purchase the TS housing yes it's $395. But if you are buying the complete turbo, it doesn't add anything extra to the price of the turbo. For arguements sake, you can pick up a twinscroll GT3076R for under $1400 easily. If you hunt around, with a little luck you can get them for under $1200.

Geoff, what does a twin scroll S200 (S256) cost?

Just to be clear, I've driven TS setups and I would argue for them on a lot of setups. But I'm interested in a 50-55lb/min sized turbo for my next setup and have been very on the fence of which direction I would go.

I like the simplicity and low weight of the single scroll single wastegate setup. Also, not buying a second wastegate gives a little extra coin to invest in other areas. I'd be pretty willing to drop that money into thin wall 321 on the header with slip joints and the Tial housing to absolutely minimize weight and I would still feel fairly comfortable with it on a street car that sees less then 5k miles a year.

Twin scroll on the other hand, I think you need to go up to schedule 10 material to help support the weight of the heavier turbo and wastetgates and the added price of the second wastegate cuts into the budget anyway keeping me away from a thin wall slip fit header. The twin scroll is considerably more heavy by this time between the second wastegate, heavier manifold, and heavier housing.

If the car sees 5k+ revs when it needs power with proper gear selection and the smaller GT30 based turbo offers acceptable response, I don't know if the response benefits of the TS holds up over weight in my particular set of goals.

 

They do, I have one on my car...

Scorke

 

S256's in the bare bones form are about 800 bucks, the extended tip ones are 11-1300.

Scorke

 

Have you driven a twin scroll big turbo?

Scorke

 

Garrett has not officially released the TS housings. ATP was able to get castings ahead of other Garrett distributers and cut the housings themselves. There is another option for a T4 twinscroll in ballbearing. You can get a 1.0 A/R T4 twinscroll with the stage V turbine wheel and any compressor you want such as GT35R.

 

I'm thinking about taking a Dremel to mine to give it an internal cleanup and smooth the wet surfaces. I don't know what/if an appreciable effect it will have, but it's just a bit of elbow grease invested on my part.

 

Show me a link of a Garrett t41.06 for a 35r.

Did you see my thread asking about extrude honing a turbine housing?

 

http://www.atpturbo.com/mm5/merchant...egory_Code=GTH

They have been available for a long while now.

What housing are you using?

I also happen to have a 1.06 T4 Undivided if that helps at all

Scorke

 

Yea I have that one. They suck. The castings are crappy. Garrett's castings are much nicer. I think u miss understud me. Garrett does not make one. I wish they "Garrett" did. It would be much nicer and most likely work better too.

I run a modified PT T4 1.06.

Also I found a T4 1.10 about a year ago. It was made for a 35R. The guy only made one. He said he was going to make many more but never did. I wish I bought that thing when I had the chance. I don't even remember his number. I think he was located in p.a. though

 

Whats so horrible about the castings? Lots of casting flash or what?

By modified you mean ported?

Scorke

 

Just a GT4202 setup that put down 800 WHP and would spin all 4 when boost hit in 3rd gear at under 5000 RPM, does that count?

I'm not going for 600+ HP though. The question I have is compared to a better spooling smaller turbo that is capable of 400-450 WHP, is there really any benefit to a TS setup for a more race oriented setup? I literally could care less about going over 450 WHP, so the argument of getting a larger turbo to spool like a smaller single scroll is a moot point.

The smaller turbo is already going to spool very well in the single scroll setup. Yes, I agree, it will spool faster in a proper TS setup below 5k RPM. But is that faster response really worth it considering transient response above 5K is going to be nearly identical?

Once the engine speed gets ~1000 or so RPM higher than the boost threshold, it seems like the difference in response is pretty minimal. Below that area though, yes, TS has definite benefits and I do not question the benefits on a street car.