with his valve timing arguments for the exhaust, he also draws on some of the Miller Cycle stuff, where by the supercharger forces all of the exhaust air out of cylinder etc. One of the problems with the Miller Cycle engines for cars (until Mazda used it in the 90's) was that they couldn't rev... I'd say the low revs that the V8 compressor ran at probably apply to this idea also- fine to produce compressed air, bad propelling a car. Also if you are forcing air into the engine at 3 bar, what fuel will you run? Diesel?

I'd say you're spot on dodge... most of the design of the combustion engine happened in the first 20 years of the car, and was all over by 1913! Someone would have done this if it were viable, especially if you could get 1.5 times the power from 1/2 the displacement. The only thing that's really changed in recent years obviously is computer control.

Still it's a better effort than that exhaust into cylinder drawing from that Corvette site

my favorite part:


"It is unclear if there could be any circumstances where flame or spark from a power cylinder could get backwards past the intake valve, so research would be necessary in this area to avoid any explosion hazard of the air tank chamber igniting. Safety check valves might be appropriate to avoid such problems."

I think it's pretty reliable that the spark doesn't get through closed intake valves and ignite fuel in the intake manifold.

he seems to think getting 3:1 compression somehow makes more air leave a cylinder than entered it.

Internal combustion engines have been around for over 115 years & MILLIONS of professional engineers & home tuners have come up with just about every imaginable means of extracting more power from almost every engine design ever made.

To think that this concept has not been thought of, & even tried before by somebody somewhere would border on the delusional. If the idea had any merit, any chance of success, it would have been tried & developed decades ago.
That it isn't a well known conversion already speaks reams about its viability.

Back when the Co-Axial phone cable was being run from Sydney to Melbourne in the early 60's, the PMG [Postmaster Generals Department] had a small fleet of mobile workshops that maintained the heavy machinery in the field. Some of these were Bedford busses that were fitted up as workshops & they had Johnston compressor just inside the entry door on the left.

These compressors were in fact a side valve [flathead] Ford V8 that used every second cylinder in the firing order as a compressor. [end cylinders on one side, centre cylinders on the other] This made it a self contained, self propelled unit that ran as a V4 engine & a V4 air compressor which was just the ticket for working in the paddock. I only ever saw one, & only for a couple of minutes.
I don't remember too well if it had special heads, or modified originals but the exhaust valve in the compressor cylinders had been replaced by some sort of plug & it would suck through the inlet valve, & exhaust through a one way valve in the head.
The inlet side used a light valve that was held in place by a light spring so that the valve would suck open whenever the piston went down the bore & at the low RPM's that it ran at, this system worked just fine

Ford V8's had a dual plane inlet manifold as original & each plane fed every second cylinder in the firing order, so fitting a single throat carb that fed only one half of the manifold allowed the other half to feed the compressor cylinders with filtered air only.

The unused plug leads were terminated with a fitting that was screwed or bolted to some part of the engine to earth them out & this removed any need for further mods to the ignition.

It was both bizarre & beautiful since it actually worked & allegedly worked well.

If you use the V8 dizzy, remember you have to join every 2 plug leads together, so you get 2 sparks per cylinder.

Much better to put a V8 dizzy on an A series.
I heard they rock

Haven't gone to the site or read but think I have the gist from comments above.

I reckon it would create zero boost given the "supercharger" has the same volume output as the remaining "engine" capacity. (and I can't see any reason the "supercharger" would have superior cylinder filling and therefore output over the "engine".)

Theory might work for a V8 if you used say 3 cyls as the engine and 5 as "supercharger". One of the reasons Superchargers are overdriven say 1.5 times engine speed.

Ignores the frictional losses etc of course.

Agree it has more promise than the "direct Exhaust Injection" though!!

I guess this is half the way there lol

http://datsun1200.com/modules/myalbum/photo.php?lid=4379

drag would be greater. the setup the guy has gone on about you are pushing pretty much pushing a whole other motor. while a turbo or supercharger would have far less drag because it uses far less components if much lighter and much more easier to fix if something goes wrong

shouldnt the drag be the same, as cylinders are only working half the time anyway!

Yes it was D who talked about it maybe six months ago. He posted a series of links about it, which went deeply into the benefits. He also talked about trying it with an a series i think.

It may work, but why??
Turbos and superchargers do pretty much exactly what was described. Same problems also, apart from having to drag a large tank of compressed air around.
Sounds like someone is doing an engineering course or something and smoked too much green.
Id reckon the author has probably never actually built a motor, or even changed their own oil.
Imagine the drag created by 4 dead cylinders or cylinders compressing air without a burn cycle.