S13 Twin Turbos Non-Sequential

[90RS13]

Why not try it with all 4 pipes to one turbo and having the exhaust from the first turbo spool up the second?

That is a compound setup.

Did you copy that out of a magazine? Ive read that nearly exact same thing (including little formula) somewhere, i just cant remember.

I'm pretty sure that one of the import magazines had an article about pressure ratios, and compound turbocharging. I can't remember which though.

I posted on this in the forced induction thread a long time ago at nico.
but I think a large racing wastegate could easily act as the switcher. its got all the diapraghms and such. you could run the exhaust first into a Y pipe, one of the legs gets the small turbo the other gets the large wastegate. The wastegate is closed at low boost, at, say 7 psi the wastegate sense the boost, opens, but instead of venting the smaller turbo it just opens the Y, so all that pent up exhaust is still going through the small turbo, but also flying around it, slamming into the larger turbo, making like the crazy NAWS on fast and furious 2.
I see no reason why it wouldn't work. Want me to make a photoshop drawing of it tomorrow? I like making photoshop drawings.

sounds good. The new BMW deisel engines use a nice sequential setup. It uses almost the excact setup you are describing. Makes for very quick spooling, and instant throttle response. The wastegate i think would have a tough job though. I'm thinking. The wastegate is set to relieve pressure at 7psi. Then it starts letting the extra gases go to the bigger turbo. Then both turbo's will be making boost, so the engine will have alot more aire flowing through it. Eventually the wastegate won't be able to flow enough, and too much gas will go to the first turbo. It will end up spinning faster than you expected.

[/QUOTE]Want me to make a photoshop drawing of it tomorrow?[/QUOTE]
yes, some people might not be able to visualize it.

I like how this thread is going. It's not getting covered in pointless posts, from people who post just to see their name on the thread.

[Bluewind]

Originally Posted by 90RS13

I like how this thread is going. It's not getting covered in pointless posts, from people who post just to see their name on the thread.

I'm with you on that. I think everyone is mutually interested in this set-up. It's not the average thread, and basically the people with knowledge and understanding are the people visiting this thread.

[90RS13]

I thought of something for the wastegate problem that I mentioned earlier. Using more than one wastegate would be good. For fun let's say you use 4 wastegates. They're set for 7psi. At 7psi, they will all start to open, like normal. Then when you're flowing alot more you would have alot more flow, (becuase of all the wastegates), while still keeping the first turbo at a lower rpm. With only one wastgate when set at 7psi, when the engine's flowing alot of air the wastegate won't be able to pass all of it, so the first turbo wil take in more than you want. Am I explaining this well? See,

one wastgate 4 wastegates
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See, more wastegates can flow more gas when needed, but can also keep the first turbo from spinning out of it's effeciency range. Does this make sense?