Has it been done before? Can it be done?

nightmare mode
but for serious cvt driven centrifugal superchargers do exist

Couldn't you just go for a twincharger setup but delete the turbo?

The mad max blower was fake.

OP just needs a controllable diverter valve

>i want to make something that will outweight the extra fuel consumption cost for years because ...

>I want a turbo
>I don't know how to mount a turbo away from the engine

Serious question guys; wouldn't it be easier to simply bypass the compressor? I mean, using a valve that connects intake and outlet of the compressor so that you can practically deactivate it opening the valve.
I think it is called dead heading. I know it is not as efficient as using a clutch, but it would probably be easier to do.

>"I want power on demand"

What is Nitrous Alex.

> wants power adder
> wants mpg

Ugh.

Get some self control and disappoint and stay off it. Mpg improves.

Yeah I think thats the way to do it.

"Turning off" the supercharger with a clutch will either cause the engine not to run or it will be a huge drag on volumetric efficiency. If the vanes in the SC aren't turning, they don't let any air go by.

Wouldn't running a valve "open" bypass this issue?

That's what he just said asshat

Op, If for whatever reason, you really want to do this, go get a whipple twin screw, they have an Intercooled bypass valve, then get an ac clutch, or a clutch from an mr2, or Mercedes, and press that into the whipple pulley. Then get two throttle bodies, one on the compressor inlet, the other before the bypass, and use a dual cable throttle cable for a motorcycle to hook them both up to the pedal. Get a switch that deactivates the clutch, and opens the bypass, and also possibly switches to a different tune. Good luck.

You do realize that MadMax(original) was just a movie, right

gvet an electronic clutchj like on the ac compressors

>LS1 camaro
>worried about mpg after a $5000 blower install

ls1 trans am here

you are making us look bad

>Am I wrong in thinking boost = fuel consumption?
No. You can use a bypass valve for part-throttle operation, which means you aren't building any boost at all during cruise or mild acceleration. This lack of boost means the ECU won't have to throw more fuel at it, and you end up with better MPG. Bypass valve closes when under heavy acceleration, ECU throws more fuel to keep the AFR sane, and then you end up with more power.

>but for serious cvt driven centrifugal superchargers do exist
procharger.com/procharger-i1
Here ya go. Perfectly sized for the LS1, but they don't have kits for the LS1 Camaro yet.

The idea has been around since Roots blowers got into the hotrodding market. It's called a bypass valve, because it bypasses the blower like you describe. You'll still have some parasitic loss on the compressor, but it's a lot cheaper and more reliable than a clutch setup.

It already has an on and off switch. It's called your foot.

> If the vanes in the SC aren't turning, they don't let any air go by.
If you turned off the centrifugal, airflow would simply turn the compressor wheel. It wouldn't be a major drag like you describe.

There's no point to doing this. Supercharged engines get good mpg if you leave it out of boost. Hellcats can reach low 20's on the highway.

>Supercharged engines get good mpg if you leave it out of boost. Hellcats can reach low 20's on the highway.
Both of these are because of bypass valves, which is what OP is looking for.

Such a bad ass set up
youtube.com/watch?v=PjQA8lqyqfw

so now you have tons of pressurized air just blasting around in your engine bay and still have parasitic loss on your engine. this is dumb

>normies comes to Veeky Forums
>posts normie memes
>asks normie questions

I dont know why you guys entertain these people

The air isn't compressed if both ends of the supercharged are at atmospheric pressure, so there's no work being done, and therefore, there is no parasitic loss due to compression. You'll only have some minor losses due to spinning the rotational inertia of the supercharger, but those are completely negligable compared to the engine internals, especially in the case of a centrifugal.

>a compressor stops compressing air if the chamber where the compressed air is deposited is at atmospheric pressure

pretty sure thats wrong user, the compressor turbine still compresses air, its not like its volume changes

Going from a three inch circular inlet to drawing the same amount of combustion air through the compressor housing and the very restrictive static compressor would be a massive drag, as old mate described. It's not a total seal, but it poses a huge restriction for the engine to try and draw through.

>Am I wrong in thinking boost = fuel consumption?
No but the problem is that you'll have a map that's pumping more gas and will probably have bigger injectors to do so anyways so you don't fuel starve the engine when you get in boost
Basically it'll be running rich as fuck all the time when you have the S/C turned off

>what are switchable maps

The bypass valve basically means that the entire restirction gets bypassed though. That's what it's for.

Don't lie, you just want it so you can pull a red switch and take off like Mad Max.

>what are searchable maps
not enough to compensate for the minimum duty cycle and flow rate of the injectors that dude thinks are needed

if your running that much boost just run secondary injectors
same concept as carburetor secondaries

aussies here we love them, procharger a cool

i don't know if i love these guys or hate them

The AW11s supercharger had an electromagnetic clutch for this reason.

Realistically it's not easy to do what you want to do as a single person.
What you can do is create an on demand boost leak that would mean no boost going into the engine. You would still lose power though because the supercharger would still be spinning.
This "on demand boost leak" works well in turbocharged cars though because you don't have a parasitic loss so leaking out all the boost pressure doesn't do any real damage and it increases your fuel economy.
It's a concept I plan to put into practice when I turn my AW11.

>What about my boost = fuel consumption question?
With a supercharger yes, since it creates high parasitic losses.
With a turbocharger that is more about the setup, if it is done well, a boosted engine can be more efficient than a NA one.
pic related is the brake specific fuel consumption of a boosted engine.
Everything under 250g/kWh is good

A hybrid conversion or a little boost with a turbocharger would make this possible.

I'm aware of the bypass valve, old mate wasn't and thought that trying to draw combustion air through a static compressor wheel won't be an issue.

Please do. Also, please post a photo of the first time you take this contraption onto a freeway, open your boost leak, overspeed the wheels and shaft as that's what a turbocharger will do if not under load yet has significant drive available, and promptly shit your turbocharger out the exhaust.

So basically there is a minimum amount of fuel an injector can deliver??

Also if thats the case couldn't you get around this by adding secondary injectors, like in a wet nitrous system? That way when you disconnect the charger you just run one set of injectors

Yes and yes.

The larger the injector, the more fuel added per percentage of duty cycle. Idle can be difficult with monstrous injectors and pump fuel.

You can use sub injectors in different ways. I use EMS products and they can have a sub injector map that is activated based on the normal fuel map. When the normal fuel map puts more than a variable duty cycle on the injectors, usually 80%, the sub injector map is active.

Holy fuck how stupid do you think I am? I know I can't run 0 psi (gage) and expect the turbo not to shit itself. The point is you can bump it down to somewhere along the lines of 3 psi and reap economic savings without sacrificing any part of the system.

I presume you are incredibly stupid if you honestly think you can move to the left of the compressor map (less volume) and down (lower PR) while increasing shaft speed and somehow believe you can gain any sort of efficiency.

If you bleed off combustion air, the compressor has still undertaken the work required to compress said air. That requires enthalpy from the engine that has now been used to do work by the turbine wheel. More importantly, you want to consume a larger volume of air (right on the map) yet operate at a lower PR (down on the map) than the compressor outputs at a given shaft speed. For the majority of compressors available today, moving right but not up puts you outside of the compressor's efficiency range very quickly. So what you think you gain by running at a lower PR by bleeding you lose in the steep reduction of combustion air density.

So your idea of peak efficiency is to complete more work, requiring a higher level of enthalpy but bleed off the excess combustion air placing the compressor in a situation where it is not efficient to use less liquid fuel.

Liquid fuel that would not have been consumed to do work on the turbine wheel if the whole turbocharger was simply 'turned down' by opening the wastegate sooner.

Can you not see that your gains in efficiency will not be realised, and that the gain you are hoping to make would be realised if the turbocharger was not bleeding compressed air and instead was simply operating at a lower PR and level of volume?

Ever questioned why there is not a single turbocharging system that is not a backyard job on the internet that operates the way you think it will?

What you are looking for is a nitrous system. Nitrous will safely and reliably give you the results you are looking for. It will cost less andamage be easier to set up as well.

you need one with a clutch like mercedes kompressor

the one in max max was a fake they used a washing machine motor on top of standard 351 clevland . grew up with this film. all superchargers are belt briven and are either on or off. they dont use clutches.

SC12 and SC14 use a three-sprag electromagnetic clutch to engage and disengage with a bypass valve to allow air when disengaged. They aren't big blowers but Roots blowers nonetheless.

>I want to be able to "turn it off and on".
What the fuck for?