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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Location: cambo
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Tue, 17 May 2005 03:29
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without going to that link i think it would cost too much money and be way to involving for the average enthusiast to convert an engine to miller cycle. i know people have spoken of doing it to a 4agze, but dont know of anyone who actually had a crack at it.
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Tue, 17 May 2005 03:33
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higher compression, different cam profile... not that much different really..
the reduction in pumping losses would be good, but i suppose it is not so great for all out power... might be good for non-dyno-queens
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Location: parra
Registered: June 2003
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Tue, 17 May 2005 11:16
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how much is it to get totally custom ground cams made???
and as the gze charger doesnt make boost on idle how would it idle??? you'd have fuel and air pushing out the inlet if you didnt sort that out...
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Location: cambo
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Tue, 17 May 2005 11:24
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you just lock the clutch on the sc
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Location: Brisbane
Registered: February 2003
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I supported Toymods
Location: Perth
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Tue, 17 May 2005 14:13
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Someone give me a wad of cash, a Motec, a 1GFE and I'll give it a try. You should be able to somewhat replicate it if you had full control over the vvti.
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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I supported Toymods
Location: Perth
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Tue, 17 May 2005 14:28
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Pssht, I thought the whole point of a Miller cycle was to have a higher static compression. The 10.0:1 compression of the 1GFE suits that just fine.
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Location: Brisbane
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Tue, 17 May 2005 23:09
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A new Century? That would have to be a big wad!
If you happen to find a crashed Century with engine intact, be sure to let me know.
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Location: c'town, NSW
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Tue, 17 May 2005 23:14
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V12 century are about $30-60k on www.goo-net.com
give it 5 or so years.
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I supported Toymods
Location: Perth
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Wed, 18 May 2005 03:03
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Norbie wrote on Wed, 18 May 2005 07:09 | If you happen to find a crashed Century with engine intact, be sure to let me know.
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*kicks Norbie*
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Location: Brisbane
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Wed, 18 May 2005 03:49
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Some things are never forgotten...
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I supported Toymods
Location: Perth
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Wed, 18 May 2005 03:54
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And never will be
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Location: Rocky Mountains, Canada
Registered: May 2002
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Location: On your mum!
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Wed, 18 May 2005 07:04
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M.W.P. wrote on Wed, 18 May 2005 15:39 |
oldcorollas wrote on Wed, 18 May 2005 00:02 | well, it's basically to reduce pumping losses that are incurred in your standard otto cycle engine, so you get better performance from a smaller motor, AND better fuel economy (like 10-15%?)... think of it as Otto-optimisation
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Strange.
The article talks about using a high comp engine, but closing the inlet cams late to artificially lower compression reducing pumping losses.
Not by running "true" low compression.
I wonder what difference it makes....
Actually, whats the difference between what you are suggesting oldcorollas over what is the lowering of compression and increase of boost on normal hi-po engines?
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Actually, "artificially" is a very poor choice of words for this. It refers to reducing the dynamic or true compression and there is nothing artificial about that.
The immediate differences that come to mind are better rod angularity (better geometry to make the squeeze), and a quicker rate of compression (more efficient compression) and lower compression temp (adiabatic efficiency), the article also suggests lower ignition temperatures.
Lower comp and higher boost aims to push the torque curve further up the rev range, the idea of the method described is to make better power in the realm where most engines live.
This is my understanding and I look forward to learning more as this thread strings along.
P.S Is there an echo in here? I seem to recall writing here somewhere before about later closing of the intake valve to reduce the dynamic comp?
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Location: Brisbane
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Wed, 18 May 2005 09:43
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I thought the major benefit of Miller cycle was a low compression ratio in conjunction with a high expansion ratio... something that's not possible with a conventional Otto cycle engine. Low compression engines can be boosted but have poor thermal efficiency because of their low expansion ratio. Miller cycle gives the best of both worlds.
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Wed, 18 May 2005 11:09
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zactly...
my guess is that for a given boost, you will have a slightly smaller 'effective capacity', but greater efficiency.... what better reason to run a few more psi
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Location: Perth,western australia
Registered: December 2003
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Wed, 18 May 2005 14:18
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sprintex superchargers ar emade right here in WA.
i have seen their workshop.
mmmm so much supercharging goodness...
however- corky bells book supercharged! has a good section on the miller cycle and how to set it up etc with a supercharger.
cheers
Dom
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Location: On your mum!
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Fri, 20 May 2005 06:35
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Thanks Norbie and oldcorollas, that maketh much sense indeed.
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Location: Brisbane
Registered: August 2004
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Sat, 21 May 2005 05:32
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Sounds very cool, is something like this up and running from Mazda at the moment do you know?
Glen.
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Sat, 21 May 2005 08:00
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Gleno28 wrote on Sat, 21 May 2005 15:32 | Sounds very cool, is something like this up and running from Mazda at the moment do you know?
Glen.
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i guess you didn't read the link in the very first post then
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Location: Brisbane
Registered: August 2004
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Sun, 22 May 2005 01:00
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ok, i guess i meant is it in mass production yet or is that engine still a prototype, couldn't find much more info on that site.
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Location: Brisbane
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Sun, 22 May 2005 02:21
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It was mass produced in the 90's, I don't think they make them any more though. It was in the Eunos 30X I think?
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I supported Toymods
Location: Perth
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Sun, 22 May 2005 08:59
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Was in the Eunos 80(?) from memory. The 30X had a 1.8l V6
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Location: On your mum!
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Mon, 23 May 2005 07:15
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it was released in the Eunos 800M. I think that the M stands for Miller cycle.
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I supported Toymods
Location: Perth
Registered: May 2002
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Re: anyone considered changing their turbo/SC to Miller Cycle?
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Mon, 23 May 2005 07:17
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Haha, damn missing zero...and M
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