DamonB

Exactly. They called this a compound engine and they were fairly common. The engines were said to be "turbosupercharged" and were typically radials. This makes the plumbing easy and the compressors were in fact joined to the crank by quill shafts so that they not only compressed the air but provided mechanical horsepower as well. Planes fly at high altititudes where the air gets less dense and these multistage systems though complex make sense. For cars it's nothing more than a science project. You can make it work, but a properly developed turbo or supercharger would make more power with better economy; not to mention be much more straightforward in design.

Gorilla RE

iTrader: (1)

yes it is a fact that you can put a supercharger & turbo
on the same engine. in fact in the 60's & 70's semi-trucks
had both on them. and hello, top full dragsters have both.
good & bad. the good thing is that in a car it will make
turbo lag minimal. the bad thing is that you "tach out"
realy realy fast which means your ripping through gears like
crazy. hey if i had some little honda or acura i'd do it!

Gorilla RE

iTrader: (1)

O yeah they don't sell a supercharger for FD's. you would
have to have one made. but then i don't know wear you would
put it, or if it would even work.

Gorilla RE

iTrader: (1)

were

DamonB

where

Johnny Twin Turbo

I haven't seen any one mention the horsepower consumed by a supercharger, which can be bunch at high rpm. The smart way to do it is to come up with a way of disengaging the supercharger at higher rpm. Basically a sequential set up that allows the supercharger to give you your low end torque then disengages when the turbo is spooled up and ready to go. The transition point is where things get tricky. While it can be done, there are a lot simpler and cost effective ways to get more power.

Another key ingredient is that it would only make sense with a positive displacement/roots type blower not the centrifigul Paxton/Vortech blowers.

Roen

iTrader: (2)

Exactly, running a centrifugal supercharger and a turbo together, you would definitely need to make sure your wastegates could rid the boost when needed, otherwise you'd get major boost creep.

I was thinking about a system like this, where you run the turbo before the positive-displacement twin-screw/lysholm type supercharger. The air would first flow through the turbo, then the first intercooler then into the intake manifold, through the throttle body, into the compressor, into the second intercooler and then into the engine.

I think this project only makes sense when both compressors are connected in series, as opposed to parallel or sequential. One advantage of a series connection is that when you send compressed air into another compressor, you would get compression over normal. An 8 psi turbo plus an 8 psi supercharger would produce approximately 20 psi of boost at peak, but (theoretically) with only the (or a little bit more) lag of an 8 psi turbo. The disadvantages are apparent, though. The biggest one is durability and intake temp. You'd have to run two intercoolers and even then, the charge temp would still not be as cool as using one compressor.

Cgotto6

iTrader: (8)

Why did you resurrect a thread from 03?

Kento

Good luck trying to fit both in the extremely limited space of the FD's engine compartment...

There's a reason why this thread died off in Feb 03...

RE-Amemiya

Don't know about if you could on our cars...but you can on the Subaru's

Heisenberg

iTrader: (3)

This may be true but with a supercharger it takes HP to make HP because of the pulley. Turbochargers apre pretty much considered free HP.

Kento

...and that does a lot of good on the 3rd Gen tech section because...?

OneRotor

iTrader: (3)

Eaton is working on a twin charged VW Golf Wagon (my uncle is chief engineer on the project). I don't know any real details, except they started with a 1.8t and a 5 speed. Sport Compact Car featured a twin charged Mini in one of the issues i got over the summer.

Kento

http://www.autoblog.com/entry/1234000180055673/

When the engine is mounted tranversely in the engine bay of the car like the Golf, you have plenty of room to play around with ideas like this. Even then, however, getting both forced induction systems to work together without issues is a tall order. The FD's extremely low (in a comparative sense) hoodline and lack of room next to the intake/exhaust ports precludes trickery like this, unfortunately.

enkeirp02

saw this a couple weeks back and thought it may apply to this thread.



http://www.honda-tech.com/zerothread?id=1360306

Kento

Again, the Subaru's flat-four engine configuration and sedan hoodline allows plenty of room for experimentation like this. Even then, note how packed all the components are in the engine bay; that must have taken some serious work to accomplish. Nonetheless, an impressive job. It'd be interesting to see how everything works...

i2iceboi

well i have read about this topic on a few forums lately like the is 300 forum, but its is possible i think that a supercarged system will give the fd the low end torque while a turbo spools, but some have said that the super robs the power off at high rpm, so the super could have some clutch type of thing that disengages at high rpm (centifugal type) and as the rpm drops low enough engages again, where as the turbo will spool and add boost to hte equation, this could be a twin turbo sytem also. i have seen many examples of this twin charge type of thing, the main thing is street crede because of the work that goes into this, it is definetly not worth the added power unless u have the time and moeny then it would be extreme interesting to see something like this prevail in the 13b or possibly a 20b! with twin scroll type twin humugoes turbos that spool and add tons of boost to the 5 second rx hahaha wow wata dream, anywas heres a pictures for ur enjoyment

Prôdigy2nd

iTrader: (3)

I've thought about this problem alot over th epast few years (it is one of my dreams ot accomplish this) you could have both running properly you could have the super force air into the turbo once teh trottle was engaged to a certain point then after that have a bypass value that opens with enough vacum that the turbo sucks it air from after it has intailly spooled up, therfore if you have the super pushing air in and have a "electric brake" on the turbos turbine then you achieve this by letting loose the brake so the superchager can spool up the turbo then have the turbo take over from a secondary valve and provide boost from there on in, and have the super push into a different valve, i dunnno thats my 3.65 cents. i think it would work but would be really fun to try to get to work "Properly" to the point of satisfaction.




Prôdigy

Kento

Uh...what?

Kento

I'm wondering what method they're using to keep the SC from backfeeding the turbos...

SomeGuy_sg

First time i am seeing a super and turbo charged RB26 . The only car that i know that had both a supercharger and turbo was the lancia delta that was mention earlier in the thread. it kicked *** back in the day. Technical marvel i would say.

kento: there might be some back flow to the turbos.But the words are blocking the whole view.It might be 2 separate end tanks.

Speedworks

Volkswagen just released a 1.4 compressor/turbo engine putting out 170hp

madbouncy

Mercedes has clutches on their superchargers, just get one from the junkyard so that when the turbo is spooled you can disengage the supercharger. That or if you just run a bypass around it, it'll still be spinning but the hp lose would be like 10 hp tops since it's not pumping anything. Like they said before, the transition would be the hardest part for tuning and everything. Aslong as you use some kind of throttle on the intake to switch air between the turbo and the super you wouldn't need more than one intake or intercooler. Since only one of them is supplying boost at a time, you wouldn't be heating the air nearly as badly. The supercharger can boost far enough into the rpm band that the turbo could be fully spooled by the time you'd want to switch over. Then again if you used a twin-screw super you could probably boost all the way to redline with a constant number. The NSX has a kit for it and it provides a nice bump all through the powerband, even up at redline. However that's low psi, so it might start dying on the topend if you run the psi where we do or want. Too be honest, it's a stupid idea to do for performance (unless money is no concern for you), but it be great to just do to say you did it and show off what you made.

It's always funny to see people want to spend so much money so that their smaller engines can have a curve that mimics something like a bigger V8 engine. Though the smaller engine person had to spend a fortune. If you want a great lowend and huge top end, turbo a big engine, lot cheaper and easier.

Speedworks

it's like the airpump works *hint*

Roen

iTrader: (2)

What's with the focus on bypassing on system for another? Why not use both systems together? The twincharged Mini Cooper makes 15 psi @ 3500 rpm and full boost @ 6000 rpm. The only difficulty in that setup is proper boost clearing and accounting for pressure differences. Seems like a smart way to do things.