Turbocharging is about energy recovery... why not recover MORE?

[eclipsh]

Thus the reason I am leaning toward a series dual turbo system. 1 small, fast spooler, and a larger unit for mid to high range power... I am not talking about switching between turbos either. One would feed the second, a true compound turbo. It works on diesels, but they can handle the 50+ psi a system like that produces. I think it is doable on a 4g63, and I'm sure someone has tried it, but I think the only way to run something like that would be a pressure relief valve prior to a GM MAF blow thru intake, so you could "wastegate" the intake pressure.

Have you not seen the umpteen page thread here on 99GSTracer's sequentially charged setup? There are a couple cars running it. They are after lots of power with quick spool not energy savings but yeah, it's been done.

 

[H@xtGSX]

Have you not seen the umpteen page thread here on 99GSTracer's sequentially charged setup? There are a couple cars running it. They are after lots of power with quick spool not energy savings but yeah, it's been done.

Nope. Hadn't even searched for it. It is a distant project, if I get a chance to do it. I have only seen it done on diesels. It is supposed to be more efficient, which is why I was thinking it would at least use more of the wasted energy going out the tailpipe. It isn't new. I am still trying to come up with another idea for the wasted heat, I just don't have time to build anything just for experimentation right now, so for me it is just an exercise in thought.

 

[avenged5]

http://www.dsmtuners.com/forums/custom-fabrication/336541-my-compound-turbo-set-up.html

For your viewing pleasure.

 

[rrussell]

Here's a awesome article on what F1 is doing in the near future on using a turbo for added HP plus energy recovery.

Racecar Engineering | See Inside Page 62 | August 2011 | Zinio Digital Magazines & Books

 

[EclipticalGS]

cooler exhaust gases = more dense charge (faster spool)

For every 20* increase in IAT (intake temp), there has to be an increase of roughly 60* of EGT (exhaust gas temp) to create the same compressor outlet flow. At least this what I've seen doing research at work. So if @ 60*F IAT you achieve your power level @ 1050*F EGT, to make the same power with 0* EGT, your IAT would have to be -290* F. Good luck with that

This is why when methanol injection cools your intake temps say 20* (figuratively) you don't actually make more power from the injection itself because the colder combustion temps directly effect the heat energy made that barrels through the exhaust which is now around 60* cooler.

The power made from methanol is the advantage to start upping your ignition timing and leaning out your afrs which then in turn creates a hotter and leaner combustion stroke bettering the heat flowing to your turbo and lessening any detonation. This is because of methanols stoich ratio

In all actuality if you were to add meth injection to a car tuned for pump gas that had no knock issues, you'd probably see a slight power increase from the more powerful combustion if the same tune was kept, but not much until you tune it.

The best thing for power would be a gas with a colder burn and doesn't have the tendency to predetonate you can lean it out and run insane timing. They do this with running 100% methanol but what you gain in power you lose in having magical spark plug melting issues and insanely high combustion temperatures from high 13 low 14 afrs/ mid 20* timing at WOT.

 

[H@xtGSX]

http://www.dsmtuners.com/forums/custom-fabrication/336541-my-compound-turbo-set-up.html

For your viewing pleasure.

That is exactly what I was thinking, though he used a much larger turbo than I was considering. I was thinking a 14b and a TD05h-20g, mainly for space constraints. Very nicely done, but I bet supporting that must have cost a LOT.

 

[English_Rugby]

This is the ideal gas law:
PV = nRT where P is pressure and T is temperature. Therefore, pressure and temperature are directly related, however, heat causes expansion or pressure, therefore causing the turbo to spin. You can make a turbo spin at 10,000s of RPMS using a high powered compressor. Also, the water would cause more harm than good and cause great disparity in temperatures of the turbo when initially injected, think of the differences that methanol injection causes then apply those but greater to an object spinning 1000's of times a second.. Sounds like a recipe for disaster to me.. Good thinking though haha!