Formula for power given volumetric flow and pressure

[oldcorollas]

the eunos was a miller cycle engine, it was designed for efficiency, rather than power

the toyota SC is an Eaton TVS.. basically a twinscrew but without internal compression.

the (very) twisted lobe SC's benefit from both oblique(?) loading of the rotors by the air (relative to rotation), and also more progessive discharge = less air beating itself to hotness...

you can increase the output pressure ratio by increasing the length of the twinscrews.. and they can (sort of) be special ordered.
it is also possible to alter the inlet/outlets to change the pressure ratio, but the remaching would be beyond most ppl.

basically the aftermarket SC's are only designed to do abotu 1bar boost... but if you fed it 7psi air, then the output would be much more (1.5x2) = 2 bar boost

[oldcorollas]

edit: check out this vid for the kind of response you get..
http://www.youtube.com/watch?v=E7NkCABT-jE

[Radar]

edit: check out this vid for the kind of response you get..
http://www.youtube.com/watch?v=E7NkCABT-jE

Awesome just pure awesome!

[oldcorollas]

of course the other option is to fit a 2GR-FSE (277kw, 377Nm) or the aurion supercharged 2GR...

[GUN METAL]

I like the response, i could put that to good use

Yeah i knew what you meant the first time, but finding space for one it difficult enough let alone 2.

Any yes i have thought about the SC 2GR, .............thought that is WAAAY out of my budget

Would be VERY cool but if i was going that far i would much prefer a blown 1UZ in the back mounted north south with a bug catcher mounted on the roof !

Does anyone know if an SC12 has been put on like a really small engine, maybe like an 800cc or thereabouts, how about instead of whacking them in series how about in parrallel ?

[oldcorollas]

putting two SC12's in parallel?
the problem with SC is the pressure ratio, too high and it starts to leak back..
but the main issue is when the pressurised air in the manifold goes back into the SC as the rotors open.. this creates a lot of losses, since the air moves back and forth and gets heated up a lot.

one of the big benefits of a twinscrew with high internal pressure ratio, is that the air int he manifold will not have a driving force to move back into the SC when the rotors open.. so it saves a lot of thrashing around...

there ar elots and lots of Kei car SC's.. which would be perfect for 800cc motors

[Radar]

Hey could you use the stock sc14 to feed the twinscrew?
Hopefully that's not a totally stupid question..

[Duk]

Does anyone know if an SC12 has been put on like a really small engine, maybe like an 800cc or thereabouts, how about instead of whacking them in series how about in parrallel ?

Parallel SC12's would have the same boost limitation from the internal design problems.

Series supercharging requires a bigger supercharger to pump into a smaller supercharger, preferably with an intercooler between the 2. This is how twin (or more) cylinder air compressors work. And it's also were the term 'intercooling' comes from. The cooling of the air between primary and secondary stages.

Filling the PD SC with turbo charged air is a whole lot easier than trying to find room for another SC and mounting points and belt drive. But I'm biased

[oldcorollas]

not much point. much much better to use a low pressure turbo with a large turbine, less parasitic drag and gets back some ebergy out of exhaust too.

you could use 2 SC12's or 14's in series, ie compound charging, and have each stage have a pressure ratio of maybe 1.8... but then the first one needs to flow a lot more air than second one...

M90 as first SC then M62 as second?

edit: too slow

[Duk]

But an M90 and an M62 together would be bigger than a 4AGZE
Stack 1 on top of the other with water/air intercooling squeezed in there some how and sit the contraption above the camshaft covers with bucket for a plenum chamber
'Gun Metal Myers'

[Radar]

*edited because it made no sense*

Your outright speed will come from having a higher average torque curve rather than just massive outright numbers.

If the twinscrew is only good for about 7-10psi before the outlet temps get to hot.. Why not just ramp up the static compression to make up for the boost?
e.g. Start off with 120 nm/L instead of 90nm

[oldcorollas]

wot? ........

[Supra967]

*edited because it made no sense*

If the twinscrew is only good for about 7-10psi before the outlet temps get to hot.. Why not just ramp up the static compression to make up for the boost?
e.g. Start off with 120 nm/L instead of 90nm

Compression ratio can't match boost for power.

[oldcorollas]

*edited because it made no sense*

If the twinscrew is only good for about 7-10psi before the outlet temps get to hot.. Why not just ramp up the static compression to make up for the boost?
e.g. Start off with 120 nm/L instead of 90nm

120Nm/L takes either high inlet velocity (ie high rpm or limited RPM) or direct injection etc etc.. but not easy to do in a well behaved motor

i thought you originally meant "why not just ramp up the boost and limit RPM", but obviously not?

compression + boost is related to physical properties of the fuel.. better to add more boost with a little less compression, than run more compression with less boost.... even NA motors ping when compression is too high..

[Radar]

Agreed 100% about its better to have more boost less compression, but in this case due to the outlet temps getting hot upwards of .8 bar (1.8PR)...
I figured if you pop the compression up nothing huge i.e. 8.5:1 - 9.5~10:1 the torque of the motor should go up considerably but still be able to handle a bit of boost..
Plenty of torque throughout the rev range it wouldn't need to be running 17psi..
I dunno just the way I see it...