compound charge
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Nope; I've got enough problems tuning the carburetor on this single-turbocharged slant six.... :sad11:
Most of the turbos and superchargers available in today's market are capable of creating enough boost to blow the crank out onto the ground already... with no help from yet another boost-manufacturing device.
There may be driveability issues at stake with only one large turbo that could be addressed with a compound setup, however. Dunno that much about it.
Thanks for bringing it up...:happy1:
805moparkid
Slant and AFX Guy
i dont understand what would be gained if your runnning a blower. twin turbo's easy, but anything else just seems like a waste of money
805moparkid
Slant and AFX Guy
it really probably dosn't cost as much as you think, just the normal internal work (cams, studs, rings etc), header and the turbo
its to be different, twin turbos are everywhere. When was the last time you seen a compound charged anything. The super charger will provide the low end boost right away then when that runs out the turbo would have already built up and may even give me a better more linear torque curve. No one will ever know if you don't experiment.
Chevy rat.Two turbos, 1 huffer.......
805moparkid
Slant and AFX Guy
ok im sorry but how does anyone think that is gonna work! pushing boost into the open hat will just push the excess out the butterfly's... would want it on the pressure side
Lol,it was the 80's......Looks first,performance second.....
67Dart273
Well-Known Member
'S far 's I'm concerned, most of that is "show car nonsense."
There's always the WWII ere "turbo compound" radial, which was probably HATED by maintenance guys, who already had plenty of work to do..............
http://en.wikipedia.org/wiki/Wright_R-3350
http://en.wikipedia.org/wiki/Turbo-compound_engine
"In the case of the R-3350, maintenance crews sometimes nicknamed the turbine the parts recovery turbine due to its negative effect on engine reliability"
I would think this would apply moreso to a compound V8
Doesn't look TOO tough to maintain, whaddaya think?
There's always the WWII ere "turbo compound" radial, which was probably HATED by maintenance guys, who already had plenty of work to do..............
http://en.wikipedia.org/wiki/Wright_R-3350
http://en.wikipedia.org/wiki/Turbo-compound_engine
"In the case of the R-3350, maintenance crews sometimes nicknamed the turbine the parts recovery turbine due to its negative effect on engine reliability"
I would think this would apply moreso to a compound V8
Doesn't look TOO tough to maintain, whaddaya think?
mopardude318
Well-Known Member
not sure I understand this, but I've noticed some Audi's driving around town. usually the higher model Audi A8's (Upper 60K+) are badged "supercharged" but also most definitely have a turbo....explain?
yea **** like the is for show but rdp has a twin super charged challenger. That's actually works probably has more than 800 pound feet of torque before 4500 rpm with a good set of tires and a good launch that's easily a 10-11 second car
67Dart273
Well-Known Member
In a general sense supercharged and turbocharged are the same thing. -- Using a mechanical device to pressurize the engine.
Compound turbocharging (or compound super/turbo charging) is a great way to get the benefits of a small turbocharger / supercharger, as well as the benefits of a big turbocharger / supercharger.
Think of it this way - if a supercharger makes 8 psi of boost by itself, it's boosting the air feeding it at a ratio of 1.5:1. If you add a turbocharger that also has a boost ratio of 1.5:1, then you've now boosted the intake charge at a ratio of 2.25:1.
The benefit is you can run a fairly small second booster that spools up fast and would usually run out of airflow for the motor. Because when that small supercharger starts to run out of steam, the big turbo will begin to boost the air entering the small supercharger. The supercharger will continue to compound the air it's fed, therefore 'keeping up' with the big turbo.
Matching the big and small turbo is the tough part.
links:
http://www.atsdiesel.com/ats2/templates/template_06.asp?p=2029422272&c=36
Wikipedia quote:
Compound Turbos[edit source | editbeta]
Compound Turbo Charging (One turbo compressor wheel feeding the other) Compound turbocharging is not the same as twin turbo charging. A compound turbo utilizes different sized turbos feeding off one another to do the job of one turbo. Air enters the low-pressure turbo (the larger of the two) and is fed into the high-pressure turbo (the smaller of the two), then directed into the engine or intercooler. This is why this type of turbo charger arrangement is referred to as Compound Turbo System. Compound Turbo Chargers work in series. Multiple turbo chargers are also commonly referred to as twin turbo chargers; twin turbos are just that "twins". The two identical sized turbo chargers are the same in nature or identical is size and work in parallel. Typically each turbo is used to do one half of the work and is not in a compound configuration. The air that is compressed into the engine is not fed from one turbo compressor to the other; the air that goes to the engine is simply split between the two of them.
The compound turbo charger set up offers all of the attributes of a small and large turbo charger without the negative effect of either one of them. There is a small turbo charger and a large turbo charger plumbed in series to one another. The small turbo charger is referred to as the high-pressure turbo charger and the large turbo charger is referred to as the low-pressure turbo charger or the atmosphere turbo charger. In a "Compound" turbo charger set up the small turbo is responsible for generating quick turbo response and rapid air flow right off idle. As the engine is accelerated from idle the small turbo begins to produce boost immediately while the large turbo slowly starts to produce a positive pressure to the small turbo. The large turbo when matched properly should be supplying boost pressure to feed the small turbo shortly after the small turbo is making boost in to the engine or intercooler. If the large turbo charger is not matched properly it will cause the small turbo charger to stall and the low-end performance will suffer.
Example: 2008-2010 Ford Super Duty (6.4L Power Stroke diesel engine)
scrappydoo
Well-Known Member
Good explanation of compound boost.
[ame]http://www.motorsport-developments.co.uk/tech_articles/FAF307.tech.pdf[/ame]
[ame]http://www.motorsport-developments.co.uk/tech_articles/FAF307.tech.pdf[/ame]
/6 Matt
30 Degrees Crooked
Last week on a cummins 12 valve.
67/273 : As I get older(not necessarily wiser,lol!), I am really starting to love the WW 2 aircraft engines. So magnificently designed (AND SOUNDING).
67Dart273
Well-Known Member
Yeh............I wish I had more money and was in better shape, would love to visit some of the air museums around the country. When I was in the Navy they still had the S2 series (Stoof) and we LOVED to be around when one of them fired up.
There was a few times the FAA arrived in their nice old DC-3 to flight check our GCA. I narrowly missed getting a ride in it one time.
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