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So, the VW TSI engine is supercharged and turbocharged.
A supercharger is forced induction right? run by a fly wheel or an electric fan (laymans terms).
Am I the only person who has thought about how/if/could we supercharge our MPS motors?
Thoughts and ideas please!:huh:
Jim
I dont know why you would want a supercharger. My 2003 mini cooper s was supercharged, and the only advantage I found with it was that the revs stayed up between gear changes (flywheel linkage). I would doubt that a supercharger + turbo charger would make any difference, unless you had twin air intakes
Running a supercharger on a stock Mazda 3 though, could be an easier way to increase performance without the massive amount of mods required to house a turbo
You would want to replace the turbo for a bigger unit for starters, the stock turbo runs out of puff fairly quickly, its a great theory, but takes a fair bit of R&D, the more common setup is that the supercharger is there for low - midrange power & torque and to feed the somewhat slow spooling turbo, this boost then gets bled off once the mid - high end turbo comes in.
Sort of the best of both worlds, low end grunt with little or no lag, top end power from a high boost, high flow turbo, but similar results can be achieved with a twin turbo setup running sequentially.
Here is the solution you seek...:whistle:
ELECTRIC SUPERCHARGER TURBO MAZDA 3 6 MAZDASPEED RX7: eBay Motors (item 330273723409 end time Aug-14-10 18:15:06 PDT)
It looks totally hmm like it wouldn't work? Of will it? Who's keen to.try out?
LOL no chance at working. My guess is that it would cause more of a restriction.
Theres been setups before. A tuning shop in Japan did a skyline motor with supercharger and turbo. i used to have a picture of it, but can't find it anymore. I think it's known as Twin-charging.
someone mentioned a mini cooper
http://www.cardomain.com/ride/843287
also:
http://www.examiner.com/examiner/x-4...an-Skyline-GTR
That electric supercharger might show some effect, but that's just too ghetto.
If I was going to supercharge an MZR, I would go the smallest sprintex SC available and gear it for relatively low boost. +30Kpa for instance. take the output of the (modified) TMIC and feed it to the SC. Take the outlet of SC to FMIC. Add an additional BPV at the inlet to the SC, which I believe also has an internal recirc. This is to prevent stalling the turbo.
With the stock turbo this would probably let you push about 22psi without leaving the turbo's efficiency range, as the outlet of the turbo has less pressure to work against.
Result would need careful tuning (obviously), although it is still just boost pressure. One would be aiming for a long flat boost curve. Expect greatly reduced lag, part-throttle response.
Result would be similar to running less boost on a larger capacity engine.
JIM, Hi. Let's get one thing straight before we advance this thread too far, so we all understand what is involved. All methods of increasing induction air feed pressure to the cylinder of an internal combustion engine are methods of SUPERCHARGING. Even "nitrous" comes into this category. However, for reasons of convenience, they are subdivided into more colloquial terms and connotations of them.
Thus, what we call a "turbo" (as in the MPS) is in fact turbo-supercharging, using its exhaust to drive the turbine (gas pressure-driven) vane which is (usually) on a common shaft with the induction air compressor vanes which operate in separate adjacent chamber. Nitrous would be Nitrous oxide-supercharging, as it increases pressure, but also adds oxygen, and also improves charge density by air chilling. It has little common application as its effects are of short duration, a matter of minutes as it uses a bottle-stored source.
What we commonly term just "supercharging" is the common expression for a mechanically (including hydraulic and electric) driven vane, rotor or impeller system that, unlike a turbo supercharger [which has two chambers to keep (driving) exhaust gas and (driven) induction air separate], only has one chamber, as the vanes, on a shaft which is externally driven, only have to deal with induction air, acting as a pump, sucking air in and blowing it out under higher pressure.
There are many types of impellers. There are multiple (usually 2) interlocking lobe-style rotors, sliding vane single rotors, and fixed vanes systems that look not unlike one side of our turbochargers. They can be gear, belt, chain, or electrically driven. Some have clutches that are operated electrically or mechanically or even barometrically, via bellows, levers or cams, so that the operator can choose to have it on or not or it controls itself according to external atmospheric pressure, as in piston driven aircraft where many controls have been used to compensate for varying heights of operation and thus changing atmospheric pressure as the plane ascends or descends. Superchargers are less popular for production cars as they are often larger, heavier and more complex and require a separate drive system. Modern piston aircraft also lean towards turbocharging for the same reasons.
The VW system uses both with results of great efficiency. The supercharger is mechanically driven from the word go, and thus produces boost at low rpm. The exhaust driven turbocharger only comes on song at higher rpm, when there is enough exhaust pressure to operate it effectively. Thus the power delivery is quite linear and the power available from small capacity is relatively high.
It is theoretically possible to "supercharge" an MPS motor, but if you've seen the engine bay, you'd realize that there is little room to mount a blower and its drive system. If I was going to try it just for the sake of it, and as a quick off-the-cuff idea without thinking it through too hard, I'd try for an electrically-driven system which means it could be mounted remotely behind the grill, along with its intercooler, then I'd set up an electric clutch so it only came into play when I kicked down beyond a certain throttle opening. That would eliminate the question of full time power draw which would be considerable for they draw a few Kw. This means that it would also want to be relatively low pressure.
Another reason turbos are popular as you get a sort of "free lunch". However, the great thing about superchargers is the huge torque from low rpm, giving great tractability. Turbos are often associated with some "lag" as they need some rpm to generate enough induction pressure. The VW gets the best of both, with little compromise.
Hope this helps. Cheers.
Last time I looked at this there was some work been done into a hybrid electrical turbo charger which uses electricity to create boost when the exhaust is unable to, however those electric superchargers you see on ebay are absolute rubbish. Any dyno you see that shows more power is almost always when they have it in but not powered (maximum restriction) and then they turn it on (medium restriction). Just removing it will also gain you even more power! Half of them are made out of computer fans and are just plain rubbish. You'd get more performance out of drilling a hole in your intake and installing a straw for you to blow into.
I was thinking the main problem you would have with a supercharged/turbo charged system would be that it would make the turbo pointless unless you ran them in parrallel. If you had them in series then the turbo would be a restriction on the intake until it got up to speed and by the time it did the supercharger would become a restriction as the turbo started pushing more boost than the supercharger could handle. My understanding of the systems that use two turbo chargers is that you use two small ones that both feed in like the Supra (I believe) or you have one small and one big like the Subaru B4 which suffered from the Valley of Death (the point where one ran out of puff but the other hadn't kicked in). Although that's just my interpretation so take it with a grain of salt.
It'd be really cool to have the best of both worlds, the low down power of a supercharger and the higher top end of a turbo but I think you'd be looking at huge money for not much benefit assuming you could even manage to stuff it all into the engine bay.
Running a supercharger and turbocharger in series can be found in the diesel world. For example the Detroit Diesel 6V92/8V92 which is commonly found in coaches uses this configuration on a V6 and V8. This photo shows how the turbo blows directly into the top of the supercharger.
http://www.buses101.com/images/DCP06895.JPG
Admittedly, the reason for this configuration is that it's a two-stroke diesel, which must have positive manifold pressure (even at idle) or it wont run. So the supercharger provides manifold pressure at low rpm and the turbo kicks in to make the engine more efficient at higher rpm. You might think that one would be a blockage to the other, but it works somehow.
Another way of meeting the positive manifold pressure needs of a two-stroke diesel can be found in the big engines used where I work. The EMD710 is a V16 two-stroke diesel with a displacement of 11.6 litres per cylinder. It makes 4000 hp at around 900 rpm and is so strong it can deliver maximum power all day long. It's a turbocharged engine, but how does it make positive manifold pressure at low rpm ? The turbocharger is gear driven at low rpm and has a clutch that disengages the gear drive when exhaust gas begins to drive the turbine. Therefore the turbo is always producing boost, even at idle rpm. No turbo lag with these engines :)
http://www.emdiesels.com/emdweb/images/710Engine.jpg
I'm tempted to mention power recovery turbines, which use a device similar to a turbocharger, but instead of driving an air compressor, the output shaft is connected through gears to the crankshaft to recover lost energy from the exhaust gas which is used to increase engine output. But perhaps that's getting too far off topic, although the Mazda rotary engine is particularly well suited to a power recovery system.
If we don't all switch to electric cars in the next few years I suspect we'll see some of these technologies making their way into our cars.
not worth the time or the effort.. get a GT28 and call it a day
tesla turbine with modern materials might work for that exhaust-scavenging idea.....
Quote:
Originally Posted by kmh001
"Following the war, in order to better serve the civilian market, the Turbo-Compound[2] system was developed in order to deliver better fuel efficiency and thus economy ("gas mileage"). In these versions of the engine, three power recovery turbines (PRT) were inserted into the exhaust piping of each group of six cylinders and geared to the engine crankshaft by fluid couplings in order to deliver more power (rather than by using the exhaust to deliver additional boost as in a turbocharger). The PRTs recovered about 20 percent of the exhaust energy (around 500 HP) that would have otherwise been wasted, but unfortunately had a negative effect on engine reliability, causing many aircraft mechanics of the day to nickname them "Parts Recovery Turbines" (and worse). The failures concerned would probably have been of exhaust valves and related parts since the turbines would have both increased backpressure & increased the operating temperature of the exhaust valves causing greater wear and failure.[citation needed]"
such a great idea.. its been around in aviation since day dot almost.. (post 1945 anyway)
Wright R-3350 - Wikipedia, the free encyclopedia
will we see it on cars..? prob not.. well all be laughing at the kids trying to get more amps out of their electric buzz cars.. "back in my day son, we had real cars with turbochargers..."
"...yeah what ever pops"
:poo:
And we could drive from brisbane to the north coast without stopping overnight to rechargeQuote:
Originally Posted by Doc
Modern materials and manufacturing can make earlier concepts become viable. PRT is making a comeback. It has already re-appeared on some leading edge diesel engines and it's being trialled on the rotary as I mentioned (in an aircraft). Ya never know where it will show up next.
lol.. interesting times