Engine - air compressor conversion?

[oc3crwler]

Without the right cam and crank this would be hard on a V8. And running a V engine on 1 bank, IMHO it would destroy itself. The hole vibration damping is based on rotating mass and combustion force evenly applied per rotation.

BUT. Those crazy germans think of everything. This is a copy from WWII. And its cheap to build and maintain.

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[skipmarcy]

The firing order is correct, but 1, 3, 5, 7 is on the driver's side and 2, 4, 6, 8 is on the passenger's side; not a consecutive firing order.

And on a Ford the cylinders are 1-2-3-4 on one side and 5-6-7-8 on the other. The firing order is 1-5-4-2-6-3-7-8.

 

[handirifle]

My intention is to cut the intake manifold off from the carburetor and install an air filter system on those cylinders, remove the exhaust pushrods so the valves remain closed and install one way check valves in the spark plug holes piped to an air tank. With the exhaust valves out of action, every up stroke of the piston becomes a compression stroke and you get twice as much air. The one way valves used to be available to screw in directly but you might have to manufacture your own nowadays. The spark plug air compressors (Spark plug "air compressor") are still available but they had a valving system that allowed intake of fresh air before compressing if I remember correctly.
Smiley

One thing you want to remember, is the INTAKE valve will still only open every OTHER stroke. One stroke down is intake, the other is the power stroke, after the cylinder fired. I wonder if you could manufacture spring loaded "valves" that would seat in the intake and exhaust ports of the cylinder head? It could be something like a long screw that passed through a flat washer (something heavy enough to take the pressures) with a spring loaded valve assembly on top of it. I'll try to draw a pic and post it.

 

[handirifle]

In the image below you can see a "compressor valve" that would replace the cylinder head valves. This design is for the exhaust side. To make an intake valve the "seal plate" would be on the bottom, to open on the downstroke. The spring strength does not need to be strong. Air pressure will hold the seal plate closed in either valve.

The rod is threaded, and long enough to extend up through the valve guide in the cylinder head. The hex nut would hold the seating plate (the one with the hole in it) against the cylinder head valve seat. It could be secured with loc tite, or double nutted.

Using a valve of this design, would allow the compressor pistons to intake and exhaust every stroke, and make it a lot more effecient compressor. All you would to do is remove the pushrods for those cylinders.

 

[zmoz]

In the image below you can see a "compressor valve" that would replace the cylinder head valves. This design is for the exhaust side. To make an intake valve the "seal plate" would be on the bottom, to open on the downstroke. The spring strength does not need to be strong. Air pressure will hold the seal plate closed in either valve.

The rod is threaded, and long enough to extend up through the valve guide in the cylinder head. The hex nut would hold the seating plate (the one with the hole in it) against the cylinder head valve seat. It could be secured with loc tite, or double nutted.

Using a valve of this design, would allow the compressor pistons to intake and exhaust every stroke, and make it a lot more effecient compressor. All you would to do is remove the pushrods for those cylinders.

I love this idea. You sound like you've done this before! What do you use for the two plates?

 

[PHILIP8N]

Does anyone know what valves they use in the commercial units? Do they have a custom "compressor head", or do they just modify the stock one?[/QUOTE]

Hoerbiger Corporation of America in Pompano Beach, Florida. We call it a 2 way concentric valve. It is a very custom dedicated compressor head. No modifiying stock heads. You will nedd much large thatn 1/2" npt ports, and your will need all 4 cylinders to power the 4 that are compressing. Philip.

 

[PHILIP8N]

Without the right cam and crank this would be hard on a V8. And running a V engine on 1 bank, IMHO it would destroy itself. The hole vibration damping is based on rotating mass and combustion force evenly applied per rotation.

BUT. Those crazy germans think of everything. This is a copy from WWII. And its cheap to build and maintain.

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You would be suprised how smooth these run, I have spent a few thousand hours around them. The rotating mass has not changed. Stock crank and cam are used. Maximum speed of these units are 2400 rpm. Philip.

 

[smiley]

One thing you want to remember, is the INTAKE valve will still only open every OTHER stroke. One stroke down is intake, the other is the power stroke, after the cylinder fired. I wonder if you could manufacture spring loaded "valves" that would seat in the intake and exhaust ports of the cylinder head? It could be something like a long screw that passed through a flat washer (something heavy enough to take the pressures) with a spring loaded valve assembly on top of it. I'll try to draw a pic and post it.

handrifle,
Glad you caught that, I forgot to mention that in addition to removing the pushrods, they also put very weak springs on the valves, so the downstroke acts as another intake stroke and sucks the valves open for another charge.
Smiley

 

[PHILIP8N]

handrifle,
Glad you caught that, I forgot to mention that in addition to removing the pushrods, they also put very weak springs on the valves, so the downstroke acts as another intake stroke and sucks the valves open for another charge.
Smiley

Just like a hit-and-miss engine. I think this would work very well for low rpm compressors. At high rpm one might see intake valve flutter and/or intake valve impact damage if piston speed and velocities are too high.

 

[smiley]

Just like a hit-and-miss engine. I think this would work very well for low rpm compressors. At high rpm one might see intake valve flutter and/or intake valve impact damage if piston speed and velocities are too high.

The weak spring is only on the exhaust and the conversions I've seen were Model A and Chrysler flathead 6 so they weren't terribly high speed engines. I suppose if you had a high enough reving one, it could be a problem but as you mentioned, they run at about 2400.
I remember I had a 283 Chevy in a Jaguar XK120 roadster and had to go over 6000 before it started breaking down, which we attributed to valve float, but never new for sure that's what it was and didn't want to push it any further to find out the hard way. Of course a weak spring would aggravate the problem.