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Variable Compression Ratio on V-8

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Old Sep 29, 2009 | 09:54 PM
  #1  
manolis's Avatar
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Default Variable Compression Ratio on V-8

Take a look at http://www.pattakon.com .

The patcrank VCR in a V-8:



All it takes is four slim and lightweight secondary connecting rods and one thin and lightweight crankshaft, i.e. 5 lightweight, and cheap to make, moving pieces in total, plus one slow moving control frame.

A modified V-8 patcrank VCR has as vibration-free-operation as the original conventional V-8, no matter what the selected compression ratio is.
The rev limit is as high as the rev limit of the original engine.

The range of available compression ratios of the patcrank VCR is as wide as desirable, for instance from below 7:1 to above 20:1.

A good VCR may help the big displacement engines to pass current and future CO2 emission regulations.

Thanks
Manousos
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Old Sep 29, 2009 | 10:27 PM
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From: Mass
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Saab had a variable compression ratio engine design as well. But it used a bank of cylinder bores on a hinge that could move them slightly closer or farther from the crank.
http://www.saabnet.com/tsn/press/000318p.html

This kind of discussion may do better over in this room:
https://ls1tech.com/forums/advanced-...ring-tech-107/
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Old Oct 2, 2009 | 12:23 AM
  #3  
manolis's Avatar
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The basics of V8 patcrank VCR are shown in this simple gif animation:



The main crankshaft (red) is conventionally supported on the crankcase and drives conventionally the flywheel and the gearbox.

If you do not want to open the "exe" animation for more, you can alternatively open the:

http://www.pattakon.com/patcrank/patcrankVCR.wmv

WMV video animation.

Manousos
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