Henry Yunicks Red Hot Vapor Engine Re-Creation

Yes. Amazing progress!
Congratulations on securing an original Bourke engine.
A lot of exciting parts for the 300 six.
Thank You for the update

Just as a side note: The 240 "no oil hole" rods are becoming scarce.
AFAIK I'm the only one that has put together a 300 with 240 rods for a street engine in recent years.

The 4 valve aluminum head will need a good 6.8" long rod for naturally aspirated use.

For heavy turbocharging we have resorted to using the 6.385" small journal (2.100") Big Block Chevy rod.
 
Henry Yunick said that running the longest connecting rod to stroke ratio possible is better. According to him, there's lots of performance gains to be had. According to Reher-Morrison's "Championship Engine Assembly" there are virtually no performance gains to be had. I haven't built enough engines to hold a firm opinion one way or the other, however, here's what I do know. A longer connecting rod to stroke ratio WILL do the following: reduce piston sidethrust and slap, and reduce the angular load on the connecting rod, which will make the pistons and skirts last much longer. Coupled to fully skirted pistons for superior load distribution, and we will have ourselves a winner. Because our fully skirted pistons will be our own custom design, we can make the wrist pin bore as high as we like/can. Up and into the scraper ring if we like. With a new 4 valve head we may even be able to get performance high enough to merit putting the high nickel 300i6 blocks back in production for niche and special use cases. With modern technology like RF85, nikasil cylinder coatings, cerakote, and other technology thats come into being since 1965, we can bring this workhorse of an engine into the 21st century. I'd expect no less than a 500k mile lifespan from a next gen "big six" and no less than 2 million miles from the next generation scotch yoke engine.
 
The 240 rod used on a 300 crank allowed me to reduce the piston and pin weight by 30% plus the piston no longer protrudes past the bottom of the cylinder wall.

[image]https://www.dropbox.com/s/pphrnvn7dy5ijc8/300%20piston%201.JPG?raw=1[/image]
 
The stock piston skirt travels 1.1 inches below the bottom of the cylinder.
Generally the piston height is 2 times the wrist pin height which keep the pin in the center of the piston.

If you want to do a fully skirted piston with longer skirts the weight will still be reasonable.
It depends on the application. High rpm performance or low rpm workhorse.
Our blower pistons are constructed with full skirts and have an added support around the inside bottom of the skirt.

If you cast a new block the bore centers are 4.480 and there is no reason why the cylinder bores can't be 4.125" and be Siamese for a very thick cylinder wall and better block rigidity.
The larger bore has less open valve shrouding or will accommodate larger valves.
 
I forgot to add.
Piston skirt area is only part of cylinder side loading wear factor.

The other and possibly the more significant factor is piston balance.
If the piston's Center of gravity is off center then the piston tries to rotate in the bore during acceleration in both directions as well as the change of direction at TDC.
The object is to have the center of gravity at the center of the piston.

In addition the force on the piston during the power stroke is best centered when the piston has a flat top or Spherical dish.
 
Updates.

The investment did not go through, however this only delays inevitable success.

I've also greatly improved the design by turning it into a double acting engine, meaning both sides of the piston will be a combustion chamber. This means an 8 cylinder engine will produce 16 power strokes per crankshaft revolution, and I'll use schnurle porting to facilitate the use of a flat top piston. This will necessitate the use of a supercharger to replace the underside of the piston to pressurize the incoming charge.

I just purchased and installed a shipping container to store my lesser used tools make room in my shop for a lathe I just purchased. This is the last tool I need to be fully capable of producing my own engines entirely. I also have an original Bourke engine that will be back from the cerakote shop on the 17th.
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DeltaV":2zglje9v said:
I've also greatly improved the design by turning it into a double acting engine, meaning both sides of the piston will be a combustion chamber. This means an 8 cylinder engine will produce 16 power strokes per crankshaft revolution, and I'll use schnurle porting to facilitate the use of a flat top piston.
Thanks for the update

You will only double the power strokes per rev in a single cylinder engine.

Once you go to multi cylinders the power stroke count stays the same because you have two cylinders firing at the same time, the top of one cylinder fires at the same time as the bottom of the adjacent cylinder.
What you will accomplish is doubling the displacement for nearly the same physical size engine. (not counting the supercharger)

I would have concerns over the longevity of a connecting rod seal against detonation pulses in the bottom chamber.

Since the two Schnuerle intake ports need to point upward will there be two sets of ports per cylinder, one set for each of the two piston chambers?
 
I designed it so that one set of ports is all that is required to feed intake and pull exhaust from both sides of the piston by keeping the piston height shorter than the stroke by the same length as the height of the ports.
 
Real quick, the forums new look is fantastic!

Yes! Many updates.
First real quick, I've obtained and have completed reconditioning an original 30 cubic inch Bourke engine, one of only 4 surviving examples left in the world. I've rebored the cylinders, got them nikasil coated, treated with RF85, and coated again in WS2. All other sliding surfaces have been treated with RF85 and coated in WS2 including the rings, piston, connecting rods and rod bushings, bearings, crankshaft, wrist pins, and etc. The counterweights and inside of the crankcase I cerakoted in cerakote microslick. The piston top and top of the combustion chamber I coated with cerakote piston coating, and the underside of piston and outside of the crankcase I cerakoted with high emissivity grey cerakote. The combustion chambers outside I covered with cerakote chrom to hold in heat to get the coolant up to operating temperature fast. All I need to do now is machine glow plug adapters to convert the engine into a HCCI engine instead of spark ignited. This has been quite the experience rebuilding a veritably ancient pre-WW2 era engine. It was quite the learning experience. It made me realize that people back in the day did a whole lot with a lot less available to them. For example, instead of snap rings to prevent the wrist pin from galling the cylinder wall, cylindrical top-hat shaped pieces of felt were pressed into the hollow ends of the wrist pins! And it worked! Reminds me of the time I took apart a really old truck tire and discovered an inner tube made from an animal intestine. I'll upload pictures of the rebuilt Bourke when I assemble it.

I've recently purchased an old van-normal piston grinder that I'll restore hopefully this year to grind the connecting rods and crankshaft and etc. So thats cool. Paid $300 for it. In theory it should produce a better finish at greater accuracy than a lathe, good for crankshaft journal surfaces and etc.

I still have yet to install my leblonde servoshift lathe because my rocket heater company (rocketheater.com) has been so busy I haven't been able to keep up with demand! I've just been making stoves all this year thus far. The good is that I have plenty of money to fund the engine project finally, the bad is that I've no time to pursue it!

That being said, I have my 92cc design essentially completed and all blueprints made. All I need to do now is figure out whether I want to use an AMR300 roots supercharger or TVS V250 twin screw/whipple supercharger. I know that in most applications a twin screw is more efficient and I need to squeeze every ounce of power I can from this thing to break the 100cc land speed record, however the engine is so small I'll need to step down the RPM of the supercharger to be about 1/3 engine RPM. I've read in my old books that roots blowers are efficient at low RPM's and boost pressures, which is what I'm going for. However, a twin screw may still be more efficient at the end of the day. 0-5 PSI of boost is all I need, I just want to fill the cylinders to around atmospheric pressure, or a little more. I'll have to determine whether a twin screw or roots blower will be more efficient and better for this application. If you have any thoughts on the matter I'd love to hear them! As their names imply, the AMR300 pushes 300 cc's of air per revolution, and the TVS V250 pushes 250 CC's of air per revolution, whereas the engine hypothetically only needs 92cc's of air per revolution to fill the cylinders. To save energy I'm thinking about using more efficient roller chains instead of belts to drive the blower. I'm hoping that peak engine RPM will be no less than 22,000 RPM and as high as 30,000 RPM. I could also use a TVS V180 twin screw compressor that only outputs 180 cc's of air which will allow me to run the supercharger at 1/2 engine speed. Thoughts?
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The TVS superchargers have a better volumetric efficiency than the Roots superchargers.
The faster you spin the supercharger with resect to the engine crankshaft the sooner it makes boost.

TVS V180 is good for 20,000 rpm so if you plan on turning the engine at 30,000 rpm you can drive the TVS V180 at 2/3crank speed.
That will produce just over 4 lbs. of boost.

If you need more boost you can spin the TVS 250 at 2/3 crank speed since it is also good for 20,000 rpm.
That would give you around 12 lbs of boost with an early starting RPM.
Then you can regulate the boost pressure if you want less boost with a bypass valve between inlet and outlet or a throttle body on the inlet.

Just as an FYI.
The TVS or any of the Eaton supercharges use twin screws and are not the same as the Whipple superchargers.
The Whipple uses the original Lysholm screw and auger design.
 
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The TVS superchargers have a better volumetric efficiency than the Roots superchargers.
The faster you spin the supercharger with resect to the engine crankshaft the sooner it makes boost.

TVS V180 is good for 20,000 rpm so if you plan on turning the engine at 30,000 rpm you can drive the TVS V180 at 2/3crank speed.
That will produce just over 4 lbs. of boost.

If you need more boost you can spin the TVS 250 at 2/3 crank speed since it is also good for 20,000 rpm.
That would give you around 12 lbs of boost with an early starting RPM.
Then you can regulate the boost pressure if you want less boost with a bypass valve between inlet and outlet or a throttle body on the inlet.

Just as an FYI.
The TVS or any of the Eaton supercharges use twin screws and are not the same as the Whipple superchargers.
The Whipple uses the original Lysholm screw and auger design.

Thats good to know that rotary screw =/= whipple! I was looking at the compressor map of the TVS V180 and comparing it with the TVS V250 and the V180 seems to be a lot more efficient.
https://www.eaton.com/content/dam/e...on-tvs-efficiency-maps/eaton-tvs-V180-map.jpg
https://www.eaton.com/content/dam/e...on-tvs-efficiency-maps/eaton-tvs-V250-map.jpg

It seems to me the TVS V180 will be more efficient for the application I'm running. I'm also planning on dumping gaseous fuel into the intake of the supercharger so that the charger will double as a homogenizer to thoroughly mix the air and fuel. I was also considering to control engine RPM and torque via a needle valve that controls fuel input rather than a butterfly valve. This would be so the engine can run lean when not under full load and to allow the engine to operate at maximum volumetric efficiency throughout its entire powerband. This in theory should reduce parasitic pumping losses. Any needle valves that you would recommend?

Do you know where I can purchase a TVS V180? I've called around and cant find anyone local that sells them.
 
I would start at:
Eaton
Southfield, MI, United States Tel: +1-248-226-6200

If you want 6 lbs of boost you will need to drive the TVS V180 at 3/4 crank speed.

I don't know what size jet you would need but you could look at using a barrel valve and a nozzle from a mechanical fuel injection system.

Later on you may want to refine the fuel system so the fuel and air mixture doesn't go beyond stoichiometric where max power is made in detonation mode unlike the standard internal combustion process where the best power is made beyond stoic. Beyond stoic in this case the excess fuel gets wasted.

What will the pressure be at the point of injection?
 
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I would start at:
Eaton
Southfield, MI, United States Tel: +1-248-226-6200

If you want 6 lbs of boost you will need to drive the TVS V180 at 3/4 crank speed.

I don't know what size jet you would need but you could look at using a barrel valve and a nozzle from a mechanical fuel injection system.

Later on you may want to refine the fuel system so the fuel and air mixture doesn't go beyond stoichiometric where max power is made in detonation mode unlike the standard internal combustion process where the best power is made beyond stoic. Beyond stoic in this case the excess fuel gets wasted.

What will the pressure be at the point of injection?
I'm not sure what the pressure will be at the point of injection. Experimentation will need to be done to find out. The combustion chambers/cylinders have a thin channel around them akin to a water jacket that instead of coolant/water, gasoline will be pumped and pre-heated and vaporized in the gas jacket. The needle valve I intend on finding what position makes the most power and set the stop there. If I had to wager I'd guess that in this situation given that its a fickett-jacobs cycle I would guess that max power is either at stoich or slightly lean, but experimentation will need to be done to determine that.
 
I would think that fuel delivery has to be somewhat linear with rpm and also be able to vary the amount of fuel from extremely lean to stoic to vary the engine power.
How would that be accomplished with a single needle and jet combination that gets set in one position?

That's why I recommended starting out with a barrel valve for fuel control.
 
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I would think that fuel delivery has to be somewhat linear with rpm and also be able to vary the amount of fuel from extremely lean to stoic to vary the engine power.
How would that be accomplished with a single needle and jet combination that gets set in one position?

That's why I recommended starting out with a barrel valve for fuel control.
Agree'd 100%. The entire idea is to as you say vary amount of fuel from extremely lean to stoich to vary the engine power.

The concept is to eliminate the jets of conventional carbs and use a purely gaseous state fuel delivered via a valve that opens or closes to give the engine more or less fuel depending on load/power output desired. I was thinking needle valve but if you think a barrel valve might do better I'm more than happy to experiment. Do you have any specific barrel valves that you would recommend?
 
Kinsler is about the only company left for new parts. Hilborn and Enderle don't seem available.

A barrel valve body and spool is just so much simpler than a needle and jet with arms and linkage in a sealed unit.
The barrel valve will handle any pressure you need.

We run mechanical injection on our supercharged hydroplane. I can see something similar working for you.

In our case the mechanical fuel pump is driven 1/2 crankshaft speed. Yours could be a different drive ratio.
Fuel flow is now proportional to engine rpm. The fuel pump is sized a little larger than maximum engine fuel requirements.

A primary bypass valve is next in the system which returns fuel to the fuel tank.
It has a lightly loaded poppet valve so there is fuel pressure to start the engine with.
There is also a jet in the poppet valve assembly that determines how much fuel is returned to the tank which in turn determines the max flow to the rest of the system at all rpms.
It effectively resizes the fuel pump for the required flow.
This would be the jet you would use to limit fuel flow to Stoic.

The barrel valve is next which would be used to meter the fuel between very lean and Stoic for engine power.

The only other item in the system is a high pressure bypass which is set just above maximum operating fuel pressure and is use to cut off the pressure spike when the barrel valve is suddenly closed at high rpm.

This is all done where the fuel is still a liquid after which it can be fed to different areas to absorb heat and change state.
 
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I would start at:
Eaton
Southfield, MI, United States Tel: +1-248-226-6200

If you want 6 lbs of boost you will need to drive the TVS V180 at 3/4 crank speed.

I don't know what size jet you would need but you could look at using a barrel valve and a nozzle from a mechanical fuel injection system.

Later on you may want to refine the fuel system so the fuel and air mixture doesn't go beyond stoichiometric where max power is made in detonation mode unlike the standard internal combustion process where the best power is made beyond stoic. Beyond stoic in this case the excess fuel gets wasted.

What will the pressure be at the point of injection?

I wanted to give you some updates. Eaton doesn't actually manufacture the TVS V180, they are waiting for a big OEM to contact them to put those into production. Right now its basically vaporware. They redirected me to their distributors, but none of their distributors for direct consumers sell Eaton superchargers anywhere near small enough for the purposes of this small 92cc engine and they all kind of blew me off. So I basically must use an AMR300 roots blower for now as it is as far as I can tell the only available option. iirc Roots blowers are most efficient at lower speeds so a 1/3 ratio, just enough to fill the cylinders for the lowest possible BSFC given the technology available to me.

I just got back from the metal supplier and purchased some aluminum plates. I'm going to machine brackets for them to prepare my original 30 cubic inch Bourke engine to be mounted on to a divorced motorcycle transmission and frame. I'll be shooting for the 500cc vintage land speed record in 2022 to 2023 at the latest.

I've also since embarked on a quick and simple rebuild of the 300i6 for my 1966 F350, nothing fancy much as I'd love to use 240 rods and go ham wild I just dont have the time given that my wood stove business is taking off like mad. Pictures hopefully within the next 45 days on that. The good thing is that because my rocket heater company is doing so well, we are currently under contract for a 27,000 square foot factory which leaves us plenty of room to start other entrepreneurial endeavors, such as custom engine work. I haven't been able to install my lathe yet because I'm waiting to move into the new factory to do so.

I've also went ahead and entered into a "create the future" design contest with my project partner, Roger Richard, so thats linked below.
https://contest.techbriefs.com/2021/entries/automotive-transportation/10870
 
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