I've had this idea in my head for a while now. It's a simple concept: take a turbocharger and attach a clutch pulley to the input shaft which is driven off the crank. The idea is to spin the turbine when the exhaust pressure is low, then when enough pressure builds up, the clutch disengages and the exhaust gasses spin the turbine.

 

Kind of like a centrifugal supercharger with a rear housing.

 

Would this kind of concept work, or am I just dreaming? It would be more compact than any other compound setup and more simple too. I know it's not a good idea to put any side loading on the shaft, so maybe it could have some sort of bracket to brace the pulley, or something.

 

Thoughts, anyone?

Edited February 12, 201511 yr by ATOYOTA

thought about what sort of shaft you would need to make any boost?

 

they already make similar, still classified as a supercharger.

It would be down to pulley size, like a supercharger. The pulley would have to be about an inch across because turbos spin much faster than superchargers.

 

 

they already make similar, still classified as a supercharger.

Is that one of those jet turbine things or does that shaft go to a remote pulley?

geared up pulley system with a turbo style housing and internals

 

That's just how they reduce the gearing for a centrifugal. Like how the impeller in a turbo needs much higher RPM to generate boost. What I'm talking about is a turbo with a pulley AND rear housing, so that the pulley takes up the slack at low RPM. Kinda like twin charging.

Have you seen the new F1 cars that have electric turbos?

They have a generator/electric motor linking the shaft between the compressor and the turbine, where the generator limits the boost pressure/turbine rpm by turning excess exhaust energy into electricity which is stored and then fed back into the electric motor to spool the turbo quickly when engine rpm is low. It's absolutely genius.

 

 

Intersting idea. But I can't see how it will work practically. A standard consumer turbine assembly is very lighy and wont like anything attached to it. Especially if its a bush bearing style.

 

Alot of turbo setups that have lots of lag are due to wrong turbo charger selection.

 

Pick the right turbo and use highish comoressiom ratio and most of the lag disappears. And tune it well of course. Plenty lf ignition timing off boost to keep it lively.

 

Slightly overdriving a turbo out of its peak efficiency is fine if you have the intercooling. So you can go a bit smaller to get boost in the lower rpms.

 

Ps. That f1 turbo setup is awesome.

Edited February 8, 201511 yr by ke70dave

I've seen a couple of examples on the interwebs of electric superchargers, which I like the idea of. Full-time boost before you even touch the throttle, or have it set up to engage at any throttle position.

http://www.superstreetonline.com/how-to/engine/0406tur-knight-turbo-electric-supercharger/

This guy has invented a twin screw with three motors powering it! You would need a bigger alternator for this though, which kinda defeats the purpose of running a non-parasitic compressor.

I'm with KE70Dave here. Days of turbo lag are pretty much gone. Turbo manufacturing technology has progressed massively and responsive and high flowing wheels are available at affordable prices now.

 

Selecting the right turbo is as simple as going one size too small if anything instead of one size too big if you're unsure. Worst case limit rpm and grab the next gear to get into the meat of the torque asap instead of too large a turbo never quite getting there possibly. Get the boost all in asap and limit rpm and it will be happy days with good engine longevity.

 

The clutched comp wheel idea has merit but just isn't what the freedom of a turbo is about

Edited February 8, 201511 yr by batmo

I'm on the same page now. :P

I wouldn't say turbo lag days are gone at all, it depends how much power you want from an engine displacement.

 

The above idea is a good one, i like it, the problem that i can see is though, that style of Supercharger that uses the turbine housing is known to be quite 'laggy' and needs some good rpm to do its thing, so the benefit could be limited.

Edited February 9, 201511 yr by oh what a nissan feeling!

The idea was more for large turbos that need a lot more pressure to spool up. Sure, you can run anti-lag timing but that limits the life of the turbo. My idea was kinda like a substitute for anti-lag.

as painful and complicated as it is twin-charging would defiantly be a cheaper and easier way to get the same result, and with enough mucking around you could get it to work ok.

or simply a turbo and nitrous to bring it up on boost?

It does sound complicated when you start adding bypass valves and such. My idea is just as compact as a conventional turbo setup so I guess it might be better suited to big engines in little engine bays.

 

Nice DP...