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As the subject states, why do twins usually have less drive pressure than a single? I would think it takes more pressure to drive two turbos than one. Insight?
 

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Less restriction because the exhaust flow is greater with that larger turbo. Just my guess. I really don't know.
 

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Just because they do! haha no i have no idea but someone alot more intelligent than us will come and set us strait!
 

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you dont have to drive the stock charger nearly as hard with vein position as you would with just the single charger.
 

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what about when its a wastegated stock charger
 

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good point you bring up!
 

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As the subject states, why do twins usually have less drive pressure than a single? I would think it takes more pressure to drive two turbos than one. Insight?

How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does
 

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How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does
A rainbow is made by the prism of light, the sun sets because of the earths orbit and rotation, and a posi-trac in a Plymouth doesn't work because, well, its a Plymouth and nothing works on those pieces of shit!!! :drink
 

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A rainbow is made by the prism of light, the sun sets because of the earths orbit and rotation, and a posi-trac in a Plymouth doesn't work because, well, its a Plymouth and nothing works on those pieces of shit!!! :drink
It was a quote from Joe dirt
 

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It was a quote from Joe dirt
The only part of that movie I remember was when the Traffic gate thing ripped the spoiler off his car! Epic
 

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:D
both the chargers on a twins kit are typically always working well within their map range vs a stock single trying to push power and out of it map range which leads to higher drive pressure
This is part of it.

The turbine ( exhaust side ) can only use up so much energy based on the size of the housing, wheel, etc. So by placing another turbine downstream of the smaller turbo, the exhaust gas is given another chance to turn a wheel and therefore you are recovering more energy from the exhaust gas.


Just to be clear, the air flow in a twins setup is:

Intake -> Primary compressor -> Secondary compressor -> Motor -> Secondary turbine -> Primary turbine -> Exhaust pipe.

That's the beauty of twins ( from the mechanics side of things, anyways ), you compress and expand the gas in two stages, allowing the turbos to work within their efficient range and also recover more energy.

Sorry to be so dry.... I'm picking up my twins next week so I'm a little pumped.:D
 

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x2^^^ the way i understand it is like this- with just a single stock charger when the exhaust comes out the manifolds and then up the uppipes into the exhaust housing of the turbo, so that little turbo can only use so much off that exhaust to spin the charger so the rest off it is kinda just backed up creating what we call drive pressure. Im guessing that when you run 2 chargers it reduces this effect because you have another bigger charger sharing that exhaust flow and therfore it can not build up so much pressure. Understand i know nothing about turbos and this post was just a shot in the dark as to how it works, hopefully trent or scott or rob will chime in here and desribe exactly why DP is reduced in a twin setup
 

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The drive pressure is less bc the air that enters the stock charger is already pressureized by the aptmospheric charger...........

Thus it has to work a lot less harder to reach desired boost levels. So the vein position is pulled way out allowing as much air to flow through it and into the atmospheric charger resulting in low egts. With non vvt chargers it is done with exhaust housing/wheel choices to match fueling......

Not to mention you can burn more fuel that is injected resulting in a more efficient burn thus less energy is lost in heat through the exhaust............

And timing is generally pulled back a little so that helps also...............

It's not just one thing really it is a combination of several factors thats end result is the same power with lower egts............
 

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How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does
One of the best lines ever lol. I use that all the time

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