[COTW 5/9/11:] STS Turbo Installed

[ALLTRBO]

Don't get too confused here, two of the same size turbos compared to only one of the exact same size turbo will indeed spool slower.

However, two smaller turbos that effectively equal the size (when added together) of one larger turbo will actually spool a little faster than the single turbo, because the moment of inertia (MOI) increases at the square of speed, and these things spin fast. The two smaller sets of wheels have a lower MOI than the one larger.
So in short, each turbo is receiving half of the exhaust, but they're half the size (of the single), but they still spool faster because the smaller wheels have less momentum to build up.

In the real world it isn't a huge spool difference, and packaging is more of a concern. A single is simpler and so has less to go potentially wrong. If sized right, it will work perfectly well. That's why STS decided to go with the single rather than dual for the LLT (and I think they might not have small enough turbos to make them usable anyway. They already had to downsize the exhaust housing as it is.)

Hopefully this clears up any misconceptions.
(BTW, yes, I am still watching this and the other turbo threads. )

[Croatcamaro2010]

i wanna turbo...

[Edge.128]

I always thought in a dual turbo setup one was smaller to spin up really fast and the other was a lot bigger to take over to put out the really big power. the smaller one was just to get things going....

i guess you learn something new every day.

anyway keep up the good work Z Madness!! I can't wait for more info on this

[ROD1]

I thought 2 small ones spool faster than 1 big one..........

[PoorMansCamaro]

Originally Posted by Edge.128

I always thought in a dual turbo setup one was smaller to spin up really fast and the other was a lot bigger to take over to put out the really big power. the smaller one was just to get things going....

i guess you learn something new every day.

anyway keep up the good work Z Madness!! I can't wait for more info on this

I believe there is a setup like this. It's called sequential turbos.

[ALLTRBO]

Originally Posted by Edge.128

I always thought in a dual turbo setup one was smaller to spin up really fast and the other was a lot bigger to take over to put out the really big power. the smaller one was just to get things going....

i guess you learn something new every day.

anyway keep up the good work Z Madness!! I can't wait for more info on this

That can be done with a series/sequential twin-turbo setup, they exist too (but much less commonly). They can get rather complex to work properly. You can find lots of info about the various setups on the internet.

What I described and what is being talked about here is a parallel twin-turbo setup, and with that you have to use two identical turbos.

Originally Posted by ROD1

I thought 2 small ones spool faster than 1 big one..........

They do, in exactly the way I described above.

[Edge.128]

ahhh ok so they do exist hahhahaha ok thanks!! but I see what you are saying about 2 the same size. so really for our cars a single seems to be the way to go. thanks for the info

[Z Madness]

Allturbo, glad you are still around. I thought you'd be lurking somewhere...hehehehe

Again, bottom line for our cars is the single should be more than sufficient for around 400-ish rwhp.

I say, knock yourself out. You got the funds and the know how, go for twins. For me, the single is fine. I am having much fun as is and still trying to get the most out of the single.

Now, when I get my Z-28, that'll be another story, if its not already Supercharged. I would definately go twins with an LS3...

[stand-al0ne]

Still around. Still subscribed. However I dont have much to contribute at this point, haha Looks like everyone has it figured out on the turbos. Doesnt sound like twins are needed at this point when 5 psi is all the motor can handle before oil starts squirting.

[CAMAR0]

Here is some really helpful information on turbo systems.

http://www.turbobygarrett.com/turbob...o_tech101.html

The 101 is pretty basic. 102 and 103 is the meat and potatoes for sizing if you want to choose a turbo yourself. If your doing twins just divide the Q (flow rate) by 2. The pressure ratio will stay the same.

[Dyk-NO]

Originally Posted by Edge.128

I always thought in a dual turbo setup one was smaller to spin up really fast and the other was a lot bigger to take over to put out the really big power. the smaller one was just to get things going....

i guess you learn something new every day.

anyway keep up the good work Z Madness!! I can't wait for more info on this

I'm thinking about this one too, this is a common set-up for import TT cars, I even read of a 1000hp TT evo built by AMS using this setup. hmmmm. .. .

[Team STILLEN]

Originally Posted by Dyk-NO

I'm thinking about this one too, this is a common set-up for import TT cars, I even read of a 1000hp TT evo built by AMS using this setup. hmmmm. .. .

Evo's usually aren't twin turbo. The engine in the Evo is a 2 liter 4 cylinder, even stroked its 2.2-2.3 liters. Generally to get to 1000 hp in the Evo, they will do a big single GT42 or larger at big, big boost numbers 40+psi.

Most of the twins you will see are in a V6 or inline 6 configuration.

[rhd]

i dont think i have ever seen a tt evo.......or any 4 banger for that matter

[littleman54321]

Originally Posted by rhd

i dont think i have ever seen a tt evo.......or any 4 banger for that matter

Twin turbos just aren't necessary on such small displacement engines. Back when I drove an eclipse, I heard of a few that had done a twin or a sequential setup, but not very many. Cost just isn't worth it.