superchargers and turbos

[Dann Tier]

I need your guys input, is it possible for an engine to have both a supercharger and a turbo?

[Rob Hall]

It's been done, Volvo and VW among others...

http://www.roadandtrack.com/car-culture/a8490/parts-department-twin-charging/

[DeeCee]

I need your guys input, is it possible for an engine to have both a supercharger and a turbo?

Rick Dobertin's Pontiac J2000 had two of both, and looked really awesome.

[disabled modeler]

Dann...Yep they sure can.  I helped a guy years ago build an engine with a 671 blower and it had a turbo as well....it can be done its just tricky..lots of plumbing.

[Daddyfink]

[Daddyfink]

[Ace-Garageguy]

Yeah, it's possible. BUT...

The problem with many of the overkill setups is simple lack-of-common-sense functionality...and I've seen a lot of it.

For instance, the way the turbos in the photo above appear to be plumbed, any boost produced by them will blow out the throttle butterflies as soon as they're opened.

Pressurized air will take the path of least resistance.

But wait...the turbos are sucking through carburetors, which are fuel-metering devices, and they're discharging into the base of the injector, which is another fuel-metering device. Ridiculous. While it may look "cool" to have all that complicated plumbing, there's little chance for it to work well the way it appears to be put together.

Think about it. 

EDIT: YUP. I just looked up the actual engine, and the throttle butterflies are FAKE, and sealed from behind. That's the only possible way this thing could work.

Article here:   http://www.hotrod.com/articles/rick-dobbertins-pro-street-nova-set-for-barrett-jackson-las-vegas/

Edited September 28, 2017 by Ace-Garageguy

[Rob Hall]

Instead of hot rod stuff, here is a practical turbo supercharged engine, Volvo's T6 4cyl, made Ward's Auto 10 best engines list last year.  Sounds like an interesting engine and approach.

http://wardsauto.com/10-best-engines/2016-winner-volvo-xc90-t6-20l-turbosuper-4

 

And this year's version, with more power and more torque, and on the 2017 Ward's Auto list

http://wardsauto.com/2017/2017-winner-volvo-v60-polestar-20l-turbosupercharged-dohc-4-cyl

 

Edited September 28, 2017 by Rob Hall

[Ace-Garageguy]

If you want to turbo AND supercharge, here's a general layout that actually works, and could be modified for other installations. Remember...it's the order the components are arranged in that matters. 

This system is from the Lancia Delta rally car of the mid-1980s, but is essentially the same as used by VW and others 20 years later.

The turbo sucks clean air through the air filter, and discharges it, compressed and heated, into an intercooler that cools it.  The intercooler discharges into the supercharger, which compresses the charge even more, and once again, heats it in the process. Another intercooler lowers the temperature of the charge before it blows into the intake manifold.

NOTE: Direct port fuel injection would be necessary for this to work best. A throttle-body system could work, with the TB fitted between the air filter and the turbo, but that's not optimum.

NOTE 2: There is a bypass from the intale pipe running over the top of the supercharger shown here. It allows excess manifold pressure to be dumped through a popoff valve to atmosphere or back into the pre-turbo intake tract when the throttle butterflies (most likely on the intake port runners) are snapped closed...much like any turbo system.

 

Edited September 28, 2017 by Ace-Garageguy

[Muncie]

Rick Dobbertin's 1965 Nova, from 1982, supercharged, turbocharged and nitrous -  more going inside that you can't see. plenty out there on the internet, Google Dobbertin Nova.  pretty cool for 35 years ago.  I don't have any reason to believe it didn't work.

http://www.streetmusclemag.com/news/video-the-original-triple-charged-dobbertin-nova-up-for-sale-again/

 

Edited September 28, 2017 by Muncie

[Ace-Garageguy]

Rick Dobbertin's 1965 Nova, from 1982, supercharged, turbocharged and nitrous -  more going inside that you can't see. plenty out there on the internet, Google Dobbertin Nova.  pretty cool for 35 years ago.  I don't have any reason to believe it didn't work.

http://www.streetmusclemag.com/news/video-the-original-triple-charged-dobbertin-nova-up-for-sale-again/

 

If you bothered to read ALL I wrote, you would have seen the link to a Hot Rod writeup on that engine I already posted.

The article states that the throttle butterflies on the injector hat were FAKE. They were sealed from the back, so the injector hat functioned as nothing more than an elbow pipe that directed mixture from the turbos into the positive displacement blower.

As I further explained with the illustrated diagram, if you can apply the diagram to what you see in the above photo, this is consistent with correct design

I'm fully familiar with any and all turbo application design theory, and there's no way in hell that thing could work if those top butterflies were functional...which, one more time, they weren't.

The throttle butterflies probably DID open and close to look "cool", but again, they were sealed on the backside and did NOT feed the engine.

There ain't no magic, and things work according to logical implementation of well understood principles.

And sorry if my response sounds unfriendly, but I actually DO know what I'm talking about.  

 

Edited September 28, 2017 by Ace-Garageguy

[Muncie]

Chase Knight's Golden Gator dragster - http://clunkbucket.com/the-golden-gator/

Edited September 29, 2017 by Muncie

[Ace-Garageguy]

Chase Knight's Golden Gator dragster - 

Looking at the OTHER side of the scoop, it's immediately apparent IT IS CLOSED TO ATMOSPHERIC PRESSURE, and only functions as an air-box that the turbos blow into...again upstream of the positive-displacement supercharger.

People often think I'm being argumentative, when in fact I'm trying to explain HOW THINGS WORK, so that modelers who want to make a passable representation of REALITY may do so.

And very often, just one picture or view is NOT sufficient to see what's actually going on.

Also very often, a verbal description of function and component layout is necessary to make systems understandable.

 

Edited September 29, 2017 by Ace-Garageguy

[Spex84]

The "GigaHorse" from Mad Max:Fury Road has twin functional engines,each with a functional blower but fake twin turbos. Looks like a blow-through rig with a hat over dual 4bbl carbs on each blower. It had dual intercoolers...but I'd need to see photos from additional angles to know if the general layout is legit.

If you want to see insane engine layouts and combinations, tractor pulling is where it's at!


 

 

[disabled modeler]

Me...I like the superchargers on their own....no turbo lag.

[dieseldawg142]

........

 

Edited May 9, 2018 by dieseldawg142

[Ace-Garageguy]

 

...when Dobbertin's came out. whatever people think, i though it was one of the coolest, wildest set-ups ever seen by gearheads at the time. people build all kinds of things to excess, it's nothing new, but it's what usually pushes the envelope....

I like Dobbertin's J2000 just fine. Nothing fake, and parts fabricated where necessary to do what they need to do. Everything looks exactly like what it is.

On the other hand, the blue Nova leaves me cold.

Just personally...if the injector hat had been functional, and had fed to the two turbos, which had then blown into a sealed plenum under the hat and into the blower (which could have been done)...real injectors controlled by the throttle-butterfly linkage and a barrel valve could have squirted into the plenum, using a real Hilborn or Kinsler pump...now THAT would have taken some engineering, and I'd be a cheerleader for the thing.

But the fake butterflies and non-functional hat ruin it for me, and impress me about as much as the old fake Cal-Custom injectors dweeb wannabes useta bolt to the tops of their carbs.

It's a carbureted car pretending to be injected.

But that's just me. I'm just a form-follows-function kind of jackass, and can't abide fake anything.  

Edited September 29, 2017 by Ace-Garageguy

[aurfalien]

Hi,

Fantastic and much appreciated info Monsigor Bill.

Curious, I couldn't find much but recall reading as a child, about a Porsche having a super charger to help low end and then a turbo to take over for the rest of the RPM band.

It was a factory racer of sorts I think.  Do you recall this or was I simply high?

Judging by the material, it doesn't sound like this would work correctly or as imagined.

 

Edited September 29, 2017 by aurfalien

[Muncie]

If somebody was looking for a something that bolted to the top of a blower, an injector hat comes to mind pretty quickly.  It bolts right on, fuel injectors or nitrous nozzles can be screwed right in and it's aluminum so connections for the turbo piping can be welded on to fit.  Probably why three of the engines here have done just that.  Maybe its a difference of opinion, but it looks like a good solution to me and one of the things that I appreciate and impressed me about the engineering on Rick Dobbertin's Nova.  function, yes, even though there is probably a plate welded behind them to seal the hat, the throttle plates fill the holes - enough for me.

Edited September 29, 2017 by Muncie

[Ace-Garageguy]

 

Curious, I couldn't find much but recall reading as a child, about a Porsche having a super charger to help low end and then a turbo to take over for the rest of the RPM band.

It was a factory racer of sorts I think.  Do you recall this or was I simply high?

Judging by the material, it doesn't sound like this would work correctly or as imagined.

Depending on how it's plumbed, it could work just like that.

What I seem to remember, on the other hand, is a twin-turbo setup with a little guy that would spool up quick to provide low-end boost, and a big brother that would keep on pumping well into the high revs.

Probably a real bidge to tune, but I like the essential idea.  

Some of these wild things were built long before electronic engine management, and a bunch of purely mechanical systems in feedback loops can be a real nightmare. There are also all kinds of potential flow-reversion problems when you have two compressors blowing into the same box. You can get into needing elaborate check valves and servos, and the more complex any system is, the more opportunities there are for a component failure.

Here's one possible plumbing scheme for a two-stage turbo setup. (Images from open internet source under "fair use" copyright definition)

          

NOTE: You COULD take the compressed air at "LLK" and feed it into a mechanical supercharger for very low end boost. WAY too much complication to my way of thinking, but entirely possible.

Edited September 29, 2017 by Ace-Garageguy

[Ace-Garageguy]

More on sequential turbo systems...again, you could blow the output from these into a mechanical supercharger if you just love complexity.

[JollySipper]

I wonder if one of the twin-charged Volvo engines would fit into something like a P1800....... What a quick little car THAT would be!!

I've seen one online with a 5 cyl turbo in it, so I'm sure it would fit, as the P1800 was a 4 cyl car............

[Exotics_Builder]

Koenig TestaRossa circa late 80's

[aurfalien]

Koenig TestaRossa circa late 80's

Hi,

Now that is one sexy BEAST!

I bet that would be a top seller as a 1/24 engine.

[matthijsgrit]

Hi,

Now that is one sexy BEAST!

I bet that would be a top seller as a 1/24 engine.

This car was actually kitted bij Fujimi

They also did a spider...

The engine is built up like this: