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Small engine modification - big gain - please review

Small engine modification - big gain - please review

Small engine modification - big gain - please review

(OP)
VARIABLE COMPRESSION RATIO (VCR) ENGINE
SAMPLE CALCULATION

US Patent 5,762,480
A typical production engine is used in this sample calculation, to illustrate the magnitude of the AC engine advantage:

Engine: Chevrolet 97Ls1 small block. 8 cylinders.
Bore: 4"
Stroke: 3"
345 Hp @ 5600 rpm
Compression Ratio: 10.0:1
Rod Length: 6.098"

At typical running conditions of this engine, the combustion will take place from 20o BTDC to  30o ATDC. The crankshaft rotation from 20o BTDC to TDC will produce piston translation of 2.85 mm while the rotation from TDC to 30o ATDC will produce piston translation of 6.28 mm.
When modifying the same engine and adding the AC linkage, the very same piston translation will be duplicated when the crankshaft rotates 88o.
To duplicate the combustion of the production engine, when modifying it with the AC linkage, the engine will run at 1.6 the rpm of the production engine to get the same piston speed and translation during combustion.
What this means is that a modified production engine can produce 1.6 times the BHP when modified with the AC linkage, or that a small engine can produce a 60% increase in BHP to replace a larger engine.
While engine height is a major consideration in passenger cars, the AC linkage will add a mere 1.4" to the height of the modified engine, however, since a significantly smaller engine will provide the BHP of a large engine, the smaller engine, with the AC linkage will yet have a reduced engine height per BHP produced.

Unlike the Wankel engine or the SAAB VCR, the AC engine is only a modification to current production engines, entailing the least amount of risk, development engineering or change to well established technology.

The AC engine combines several significant benefits in a conventional package. The confirmed advantages of VCR technology, coupled with the AC system, will exceed performance demonstrated by SAAB.

•    Infinitely Variable compression ratio.
•    Virtually no frictional load between piston and cylinder-Compatibility with low viscosity oil.
•    Increased dwell for better engine aspiration, combustion control, and non critical ignition timing.
•    Ignition possible past TDC, due to the increased dwell, avoiding pre-ignition.
•    Modified cycle for efficient combustion, allowing for a significant increase in rpm.
•    US Patent 5,762,480 internationally applied.

RE: Small engine modification - big gain - please review

"US Patent 5,762,480 internationally applied."

What does that mean? US patents are only enforceable in the USA.

Cheers

Greg Locock

RE: Small engine modification - big gain - please review

this reminds me a lot of the discussion in the better cycle engines post. (which was great)
but something is this concept doesn't add up.
re: Modified cycle for efficient combustion, allowing for a significant increase in rpm.
the rpm limits on production cars has to do with durability and cost of production, more efficiant combustion won't make an engine not come apart beyond (or at) redline.

RE: Small engine modification - big gain - please review

"60% increase in BHP---the AC engine is only a modification to current production engines---Infinitly Variable compression ratio---allowing for a significant increase in rpm."


Hummmmmmmmmmmmmmmmmmmmmmmmmmm????????????


Rod

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