Miller cycle engines

[quadcam boat]

Note, This post is 'thinking outside the square' stuff!!!!
Came across a supercharger off a miller cycle engine the other day, it was on a Mazda Euros V6. These are a V6 2.3 litre miller cycle engine and the supercharger is a twin screw lysholm.... these are the best of the best when it comes to positive displacement s/c's . This succer runs up to 1.5bar or 21.7psi!!! Anyway I don't really know much about miller cycle engines' I have basic understanding of how they work (read the article on mazda's aussie website) but what is the advantage, efficiency, or more power from smaller displacement. How would a conventional supercharger setup compare to a miller cycle setup on the same engine, in terms of power? Possibly, we could get custom cams (with mazda miller cycle specks) made for a lexus v8, fit a twin screw blower and we would be running miller cycle!
I get the feeling its a fuel efficiency thing.

Anyway, aside from that, does anyone know anything about the blowers used on these engines? Who makes them, size, ect.
I was thinking , if they run 22psi on the miller 2.3litre engine , they may run 10psi on a lexus. Not sure what effect miller cycle has on boost, Volumetric Efficiency, ect, and wheather I can work backward through corky bells formulas to work out wheather these blowers would be big enough for our engines. Maybe we would need 2 of these puppies to do the job.
Twin screw blowers are the ultimate, maybe this blower will suit us?
This is a bit of a random, rambling, post, but feel free to add your 2 cents worth!!
Andrew

 

[R-Jay]

i know diddly squat about miller cycle engines....

but i do know the car you're referring to is a "eunos" not a euros.... hehe... that's all my 2c's are worth

 

[R-Jay]

i just read abit on how miller cycle engines work and i gotta say, it's alot of messing around with timing...

just seems so wasteful leaving the inlet valves open on the compressions stroke.... mazda did it primarily for fuel efficiency reasons... we, however are after power....

so i think using these superchargers (and if they are twin screw's) on our uz's would be awesome.... miller cycle engines don't use all the boost.... it's only there to make up for the loss air by leaving the inlet valve open abit on the compression stroke... all done for a saving of between 10-15% required energy.

using on of these s/c's on our engines could see some amazing results.... and being of the twin screw variety, it wouldnt suffer from massive inlet temps like some of the other kinds....

question is.... where can you get these s/c's from????

btw, everything i wrote here is just my basic understanding of how these engines work from what i've read and interpreted....

 

[Pro]

scour the wreckers - you might pick one up for a cupla hundred!

 

[quadcam boat]

Would like to find out more about the sizing, Would we need 1 or 2 of them. I already have one.

 

[urtwhistle]

well i did summing totaly useless probly lol
sprintex.com.au says with there little calculater
lysholm 1600 will push 9.6lb into a 4litre engine that revs to a maximum of 7k rpm. thats the mak power u can get out of 1 of those superchargers 457hp is wat they project for thsoe specs.

but if u get a lysholm 2300 it will push 20psi @ 659 hp

i could do with 659 hp lol

urty

 

[R-Jay]

be careful with the chargers off the mazda miller cycle engines as i've been told by a reputable import wrecker that the bearings are the weak link... he said it was possible to change it out which totally fixes the problem....

as for miller cycle spec cams, you'd be losing power.... they only do it for economical reasons.

i'm going to try and source one now....

 

[JBrady]

You need to know pounds of air flow for the compressor. 1 pound per minute equals apx 10hp.

Miller cycle creates a longer power stroke than compression stroke. Less force is used to compress a given quantity and more energy is extracted with the proportionately longer power stroke.

Believe it or not the VVTi 1UZFE is a "miller cycle" at low rpms/loads. The cam timing is way retarded and opens late and closes late so that there is no overlap and reduced compression stroke.

 

[quadcam boat]

urty,
where did you get the flow figures for the supercharger from? I don't know what they are or how to find out. I though of filling it with kerosine and rotating it to see what its displacement per revolution is, but twin screw blowers have an internal compression ratio, and liquids don't compress!

 

[Zuffen]

The Kero would probably remove/damage the teflon coating.

 

[urtwhistle]

hey dude http://www.sprintex.com.au/BlowerCalculator/Blower_Calculator.xls
opens the page in excel
were it lists the blower name select that cell hit the down arrow and will list all the rest of the blowers that the program can calculate

 

[quadcam boat]

Yeah, but how do you know its a lysholm 1600?

 

[Zuffen]

QBC,

Did you notice on the right?

Undersized supercharger? M90.

Always said it was too small hence my move to M/MP112

Interesting Site to play with.

 

[skid]

Yes an interesting site.

Shame it doesn't have a compensating calc for different pullies and some centrifugal chargers on there.

It's interesting how you can play the numbers game.

M