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kenikh kenikh is offline
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Join Date: Feb 2005
Location: North of Exit 17
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Originally Posted by juan ruiz View Post
Some Good Porn there! Car Porn that is

Now thinking out loud people are using NOS to spool the turbos out of the hole, Me thinking WHAT "IF" I install a small Injector alike very close to the turbo, I will then have a small air bottle with a pressure switch which I can activate the system from my steering wheel which will provide the air needed to spool the turbo with a timer and eventually will cut the air supply off at a certain time?

OR Maybe I'm drinking too much Diet Coke today!
Air or NOS? If your goal is to increase hotside pressure, you aren't going to get there by simply blowing compressed air at the problem - not enough volume or storage capacity to be meaningful. I do recall reading about an experimental system years ago where they built a boost recovery system that loaded compressed air from an engine driven compressor into a pressure chamber that would augment pressures for the split seconds between shifts that pressure was unstable, but that system proved to be overly complex and heavy for the benefit.

In the past, "anti-lag" systems have used tweaked ignition timing and late fuel combustion to generate explosive pressure waves timed to optimal opening of the exhaust valve for transmission to the compressor, specifically to increase transient hotside pressures and subsequently reduce lag between shifts and at dile. The downsides are that the noise they produce is horrible and the violent combustive nature of the process demolishes the turbo in short order. These systems were generally used only in race cars that receive full teardown between races.

VTG has proven to be more reliable and as effective.

In terms of assisted rotation at idle, this is being addressed in other ways, most notably via "e-boosting", which uses an electric motor to spin the compressor when exhasut gas velocity is low. While dated, this 2006 interview summarizes the thinking that is beginning to find practice today:

Originally Posted by interview with Garrett’s Martin Verschoor
E-boosting stands for electrical-assisted boosting; by incorporating a very high speed electrical motor in rotating assembly of a turbocharger, you can drive it up to very high speeds, before you have exhaust gases to do so. It is very powerful, specifically when there is no exhaust gas available, such as at idle, or in stop and go.

It is entirely integrated inside the turbocharger, with virtually “real-estate” penalty to speak of. The size of the electric motor is about an inch long. It makes the turbocharger an inch longer, with no impact on the timing and virtually no impact on the weight. The trick is to make electrical motors are capable of motoring more than 120,000 rpm and withstand mechanical loads in excess of 200,000 rpm – because turbos spin that fast.

The other challenge is to get enough electrical energy into their designs. The majority of cars use 12 volt or a 14-volt alternator.42 volt would be a significant help. But we believe that electric boost is feasible with 12-volt systems. The prospect is very real for electric boost. You will see it in premium diesels such as the Renault Aspach (sic) or the Peugeot A06 (in Europe). They have limited space and need lots of power density and bottom end. I also clearly see it in high-end gasoline engines, built for high performance.

I could imagine it in a (Chevrolet) Corvette or (Ford) Mustang Cobra like vehicle, having an electrical-assist turbo. If you go to 42 volt or a hybrid, e boosting would also allow very aggressive downsizing of the (IC) engine. This would allow very aggressive downsizing of the engine. Instead of applying a three-liter V6, you could apply a one-liter internal combustion engine, equipped with an electrical boost turbo plus an electric motor. You can only do extreme downsizing – 50 percent or more – with electrical assist turbocharging.
There are already units in test and production today:
Advanced Propulsion Technologies, Inc.
eBooster by BorgWarner Turbo & Emissions Systems

Link to the technical paper from B-W on their e-boost technology:

The one thing that the "hybridization" of the world's car fleets is that electrical motor development for automotive applications has really accelerated.

- 1965 911
- 1969 911S
- 1980 911SC Targa
- 1979 930

Last edited by kenikh; 06-11-2010 at 12:04 PM..
Old 06-11-2010, 11:59 AM
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