#360 free machining brass for a head button?

[Charles Perdue]

Mr. Jim, have you personally tried a 360 brass head button in comparison to an aluminum head button on a water cooled RC nitro boat engine running on your dyno or in your boat? If so, what were the results?

Charles Perdue

 

[Joe Warren]

Mr. Jim, let me tell you my thoughts.

I have played with a lot of different materials for making head buttons. Aluminum in 2024, 2011,4032, 2017, 6061, 7075, 7068 and more. Stainless steel 303. Alloy steels. 110 copper. 544 bronze and 360 brass.

From what I can tell, there is an optimum chamber temperature for horsepower and RPM on our nitro engines. Not too cool and not too hot.

With a water cooled head, using 360 brass for the head button material, I have found that is very close to maintaining this optimum combustion temp during a run. It even makes the water flow rate less sensitive.

With an air cooled head the 360 brass with not work because the heat dissipation rate is too slow. This allows the combustion chamber temps to run away causing the engine to detonate and this adds even more heat to the chamber. The aluminum alloys are much better in maintaining these optimum chamber temps with their higher heat flows.

When using aluminum for a head button even with regulating the water flow it is difficult to keep the chamber temps in the sweet spot temp as it is above 212 degrees, the boiling point of water. A pressurized system is then needed, adding to the complexity of our toys.

These are just my thoughts after playing with the different head button materials. What do you think?

Charles

Charles when we ran the river years ago with BIG BLOCK CHEVYS and Jet drive we looked for anything that would improve LOADED RPM. We found twin 200 HP Nitrous Plates on a Tunnel Ram intake on a 2 - 4 barrel set up was the ticket to add 3000-3500 loaded rpm. It was the Compressed Oxygen we were looking for & it took 3 times more fuel pressure to keep everything Happy while you were ON the Button.......... Most Nitro R/C Marine engines we run today are overcooled. Sometimes it is the application... it allows for the prop to unload & the engine & model is now traveling at a higher speed and the water flow increases too. Some engines are designed better to allow the engine to make a little more heat than the water flow can remove. But Most are Over cooling the way they come from the mfger. I`am sure you know now the advantages of Brass Head Buttons. To date for me........ It is the Best Performance Part that can be Put on a Boat R/C Engine. If someone is making one that is better? out of a different alloy? I would like to test it. We are running the same volume that worked with the alum head buttons. The volume has not been changed it is Only the Alloy making the difference. And the Big Engines have Picked up about 3000 Loaded RPM. & That is Hard to Find Normally!!!! I dont care what you change... I I got to say is BEEP BEEP!!!!!!!!

 

[Andy Brown]

Mr. Jim, let me tell you my thoughts.

I have played with a lot of different materials for making head buttons. Aluminum in 2024, 2011,4032, 2017, 6061, 7075, 7068 and more. Stainless steel 303. Alloy steels. 110 copper. 544 bronze and 360 brass.

From what I can tell, there is an optimum chamber temperature for horsepower and RPM on our nitro engines. Not too cool and not too hot.

With a water cooled head, using 360 brass for the head button material, I have found that is very close to maintaining this optimum combustion temp during a run. It even makes the water flow rate less sensitive.

With an air cooled head the 360 brass with not work because the heat dissipation rate is too slow. This allows the combustion chamber temps to run away causing the engine to detonate and this adds even more heat to the chamber. The aluminum alloys are much better in maintaining these optimum chamber temps with their higher heat flows.

When using aluminum for a head button even with regulating the water flow it is difficult to keep the chamber temps in the sweet spot temp as it is above 212 degrees, the boiling point of water. A pressurized system is then needed, adding to the complexity of our toys.

These are just my thoughts after playing with the different head button materials. What do you think?

Charles

Charles when we ran the river years ago with BIG BLOCK CHEVYS and Jet drive we looked for anything that would improve LOADED RPM. We found twin 200 HP Nitrous Plates on a Tunnel Ram intake on a 2 - 4 barrel set up was the ticket to add 3000-3500 loaded rpm. It was the Compressed Oxygen we were looking for & it took 3 times more fuel pressure to keep everything Happy while you were ON the Button.......... Most Nitro R/C Marine engines we run today are overcooled. Sometimes it is the application... it allows for the prop to unload & the engine & model is now traveling at a higher speed and the water flow increases too. Some engines are designed better to allow the engine to make a little more heat than the water flow can remove. But Most are Over cooling the way they come from the mfger. I`am sure you know now the advantages of Brass Head Buttons. To date for me........ It is the Best Performance Part that can be Put on a Boat R/C Engine. If someone is making one that is better? out of a different alloy? I would like to test it. We are running the same volume that worked with the alum head buttons. The volume has not been changed it is Only the Alloy making the difference. And the Big Engines have Picked up about 3000 Loaded RPM. & That is Hard to Find Normally!!!! I dont care what you change... I I got to say is BEEP BEEP!!!!!!!!

"And the Big Engines have Picked up about 3000 Loaded RPM."

3000 rpm would be good for at least 11 mph with the 1667's that you are using. Is that the speed increase that you have seen with the brass heads?

 

[Jeff Lutz]

Charles,

Have you ever seen steam or boiling water comming out of the H2O outlet? I haven't, even when running the engine 30,000 RPM+ for four minutes. My H2O outlet was never larger than .032" once the detonation problem was solved.

What I will post now, is not "what I think", but what I know from the results of thousand of dyno tests done by myself & other engine builders of high performance two cycle engines over the past 25 years.

Eminent engine builders such as Frits Overmars & Jan Thiel, who worked on engine heating problems also faced the number one enemy of any high performance two stroke,DETONATION.

Once the engine becomes thermally sound, very large amounts of HP can be developed. To deliver 1,000 watts of mechanical energy from an engine, approximately 3,000 watts of heat energy must be developed. This means 2,000 watts of heat must leave the engine by some means. If the engine in question can get rid of this heat it will be thermally sound.

What are some of the things that lead to detonation problems? If needle settings, different head alloys, improved cooling, different head designs, etc., do not help, what is the answer?

Some things that help create detonation are;

1) poor stinger design, usually not long enough but to small in diameter

2) poor scavenging, resulting from poor port geometry

3) poor combustion chamber design

4) poor exhaust out & in flow

5) large diameter piston bores with inadequate piston crown cooling, resulting in holed piston crowns

To be continued:

Jim Allen

I have Jim. 1989 my dad Bill Lutz was running a Coyote with a picco 67. Sponson water cooling inspired by Don Pinckert. It was late in the evening and the pond was slick. The water was mounted on 1 sponson and was not in the water all the time. In between water blasts, steam would come out about 3' long out of the engine. It was pretty wild to see.

 

[Joe Warren]

Mr. Jim, let me tell you my thoughts.

I have played with a lot of different materials for making head buttons. Aluminum in 2024, 2011,4032, 2017, 6061, 7075, 7068 and more. Stainless steel 303. Alloy steels. 110 copper. 544 bronze and 360 brass.

From what I can tell, there is an optimum chamber temperature for horsepower and RPM on our nitro engines. Not too cool and not too hot.

With a water cooled head, using 360 brass for the head button material, I have found that is very close to maintaining this optimum combustion temp during a run. It even makes the water flow rate less sensitive.

With an air cooled head the 360 brass with not work because the heat dissipation rate is too slow. This allows the combustion chamber temps to run away causing the engine to detonate and this adds even more heat to the chamber. The aluminum alloys are much better in maintaining these optimum chamber temps with their higher heat flows.

When using aluminum for a head button even with regulating the water flow it is difficult to keep the chamber temps in the sweet spot temp as it is above 212 degrees, the boiling point of water. A pressurized system is then needed, adding to the complexity of our toys.

These are just my thoughts after playing with the different head button materials. What do you think?

Charles

Charles when we ran the river years ago with BIG BLOCK CHEVYS and Jet drive we looked for anything that would improve LOADED RPM. We found twin 200 HP Nitrous Plates on a Tunnel Ram intake on a 2 - 4 barrel set up was the ticket to add 3000-3500 loaded rpm. It was the Compressed Oxygen we were looking for & it took 3 times more fuel pressure to keep everything Happy while you were ON the Button.......... Most Nitro R/C Marine engines we run today are overcooled. Sometimes it is the application... it allows for the prop to unload & the engine & model is now traveling at a higher speed and the water flow increases too. Some engines are designed better to allow the engine to make a little more heat than the water flow can remove. But Most are Over cooling the way they come from the mfger. I`am sure you know now the advantages of Brass Head Buttons. To date for me........ It is the Best Performance Part that can be Put on a Boat R/C Engine. If someone is making one that is better? out of a different alloy? I would like to test it. We are running the same volume that worked with the alum head buttons. The volume has not been changed it is Only the Alloy making the difference. And the Big Engines have Picked up about 3000 Loaded RPM. & That is Hard to Find Normally!!!! I dont care what you change... I I got to say is BEEP BEEP!!!!!!!!

"And the Big Engines have Picked up about 3000 Loaded RPM."

3000 rpm would be good for at least 11 mph with the 1667's that you are using. Is that the speed increase that you have seen with the brass heads?

Andy I got the 1667 props today! Thanks Just in time for Hobart... Off corner speeds, thru the corner, and Wide Open Throttle is all better... I would say 7-10 mph. Now I believe different mfger and size engines will see different results & I have not changed anything about the flow of the water from the alum heads i was running earlier this year. You know we have traveled up and down the highways for several years changing props, pipes, fuel type and percentages, Boats Boat sponsons sponsons angles, set up & I have never seen a single part pick a engine up this much.. Maybe before we were blowing a large percentage of the unburn Nitro out the pipe? & the Higher more ideal heat of the prechamber now allows you to Light it?? The Lake is my Dyno. it is the Bottom line for what you have come Race Day. & I know what I`am seeing....... Take your best engine that you already know the performance curve on and Make a Brass Button for it & you let me know what you see.. I believe you will be looking for More Prop in just a few laps. Todays Newier Hydros run a Wider Air Gap between the boat and the surface of the water, most have narrower sponsons for less contact and drag, Todays Engines make Good Power....... Speed & Performance Still Sells!!!!!!!! I will say a Set of Brass Head Buttons will compliment a Good Running Twin & you will see a Hugh Difference!! Let me know what you find??

 

[Andy Brown]

Mr. Jim, let me tell you my thoughts.

I have played with a lot of different materials for making head buttons. Aluminum in 2024, 2011,4032, 2017, 6061, 7075, 7068 and more. Stainless steel 303. Alloy steels. 110 copper. 544 bronze and 360 brass.

From what I can tell, there is an optimum chamber temperature for horsepower and RPM on our nitro engines. Not too cool and not too hot.

With a water cooled head, using 360 brass for the head button material, I have found that is very close to maintaining this optimum combustion temp during a run. It even makes the water flow rate less sensitive.

With an air cooled head the 360 brass with not work because the heat dissipation rate is too slow. This allows the combustion chamber temps to run away causing the engine to detonate and this adds even more heat to the chamber. The aluminum alloys are much better in maintaining these optimum chamber temps with their higher heat flows.

When using aluminum for a head button even with regulating the water flow it is difficult to keep the chamber temps in the sweet spot temp as it is above 212 degrees, the boiling point of water. A pressurized system is then needed, adding to the complexity of our toys.

These are just my thoughts after playing with the different head button materials. What do you think?

Charles

Charles when we ran the river years ago with BIG BLOCK CHEVYS and Jet drive we looked for anything that would improve LOADED RPM. We found twin 200 HP Nitrous Plates on a Tunnel Ram intake on a 2 - 4 barrel set up was the ticket to add 3000-3500 loaded rpm. It was the Compressed Oxygen we were looking for & it took 3 times more fuel pressure to keep everything Happy while you were ON the Button.......... Most Nitro R/C Marine engines we run today are overcooled. Sometimes it is the application... it allows for the prop to unload & the engine & model is now traveling at a higher speed and the water flow increases too. Some engines are designed better to allow the engine to make a little more heat than the water flow can remove. But Most are Over cooling the way they come from the mfger. I`am sure you know now the advantages of Brass Head Buttons. To date for me........ It is the Best Performance Part that can be Put on a Boat R/C Engine. If someone is making one that is better? out of a different alloy? I would like to test it. We are running the same volume that worked with the alum head buttons. The volume has not been changed it is Only the Alloy making the difference. And the Big Engines have Picked up about 3000 Loaded RPM. & That is Hard to Find Normally!!!! I dont care what you change... I I got to say is BEEP BEEP!!!!!!!!

"And the Big Engines have Picked up about 3000 Loaded RPM."

3000 rpm would be good for at least 11 mph with the 1667's that you are using. Is that the speed increase that you have seen with the brass heads?

Andy I got the 1667 props today! Thanks Just in time for Hobart... Off corner speeds, thru the corner, and Wide Open Throttle is all better... I would say 7-10 mph. Now I believe different mfger and size engines will see different results & I have not changed anything about the flow of the water from the alum heads i was running earlier this year. You know we have traveled up and down the highways for several years changing props, pipes, fuel type and percentages, Boats Boat sponsons sponsons angles, set up & I have never seen a single part pick a engine up this much.. Maybe before we were blowing a large percentage of the unburn Nitro out the pipe? & the Higher more ideal heat of the prechamber now allows you to Light it?? The Lake is my Dyno. it is the Bottom line for what you have come Race Day. & I know what I`am seeing....... Take your best engine that you already know the performance curve on and Make a Brass Button for it & you let me know what you see.. I believe you will be looking for More Prop in just a few laps. Todays Newier Hydros run a Wider Air Gap between the boat and the surface of the water, most have narrower sponsons for less contact and drag, Todays Engines make Good Power....... Speed & Performance Still Sells!!!!!!!! I will say a Set of Brass Head Buttons will compliment a Good Running Twin & you will see a Hugh Difference!! Let me know what you find??

Great! Good Luck at Hobart Joe! I certainly will be looking at this head material thing.

 

[steve wood]

Mr. Jim, let me tell you my thoughts.

I have played with a lot of different materials for making head buttons. Aluminum in 2024, 2011,4032, 2017, 6061, 7075, 7068 and more. Stainless steel 303. Alloy steels. 110 copper. 544 bronze and 360 brass.

From what I can tell, there is an optimum chamber temperature for horsepower and RPM on our nitro engines. Not too cool and not too hot.

With a water cooled head, using 360 brass for the head button material, I have found that is very close to maintaining this optimum combustion temp during a run. It even makes the water flow rate less sensitive.

With an air cooled head the 360 brass with not work because the heat dissipation rate is too slow. This allows the combustion chamber temps to run away causing the engine to detonate and this adds even more heat to the chamber. The aluminum alloys are much better in maintaining these optimum chamber temps with their higher heat flows.

When using aluminum for a head button even with regulating the water flow it is difficult to keep the chamber temps in the sweet spot temp as it is above 212 degrees, the boiling point of water. A pressurized system is then needed, adding to the complexity of our toys.

These are just my thoughts after playing with the different head button materials. What do you think?

Charles

Charles when we ran the river years ago with BIG BLOCK CHEVYS and Jet drive we looked for anything that would improve LOADED RPM. We found twin 200 HP Nitrous Plates on a Tunnel Ram intake on a 2 - 4 barrel set up was the ticket to add 3000-3500 loaded rpm. It was the Compressed Oxygen we were looking for & it took 3 times more fuel pressure to keep everything Happy while you were ON the Button.......... Most Nitro R/C Marine engines we run today are overcooled. Sometimes it is the application... it allows for the prop to unload & the engine & model is now traveling at a higher speed and the water flow increases too. Some engines are designed better to allow the engine to make a little more heat than the water flow can remove. But Most are Over cooling the way they come from the mfger. I`am sure you know now the advantages of Brass Head Buttons. To date for me........ It is the Best Performance Part that can be Put on a Boat R/C Engine. If someone is making one that is better? out of a different alloy? I would like to test it. We are running the same volume that worked with the alum head buttons. The volume has not been changed it is Only the Alloy making the difference. And the Big Engines have Picked up about 3000 Loaded RPM. & That is Hard to Find Normally!!!! I dont care what you change... I I got to say is BEEP BEEP!!!!!!!!

"And the Big Engines have Picked up about 3000 Loaded RPM."

3000 rpm would be good for at least 11 mph with the 1667's that you are using. Is that the speed increase that you have seen with the brass heads?

Andy I got the 1667 props today! Thanks Just in time for Hobart... Off corner speeds, thru the corner, and Wide Open Throttle is all better... I would say 7-10 mph. Now I believe different mfger and size engines will see different results & I have not changed anything about the flow of the water from the alum heads i was running earlier this year. You know we have traveled up and down the highways for several years changing props, pipes, fuel type and percentages, Boats Boat sponsons sponsons angles, set up & I have never seen a single part pick a engine up this much.. Maybe before we were blowing a large percentage of the unburn Nitro out the pipe? & the Higher more ideal heat of the prechamber now allows you to Light it?? The Lake is my Dyno. it is the Bottom line for what you have come Race Day. & I know what I`am seeing....... Take your best engine that you already know the performance curve on and Make a Brass Button for it & you let me know what you see.. I believe you will be looking for More Prop in just a few laps. Todays Newier Hydros run a Wider Air Gap between the boat and the surface of the water, most have narrower sponsons for less contact and drag, Todays Engines make Good Power....... Speed & Performance Still Sells!!!!!!!! I will say a Set of Brass Head Buttons will compliment a Good Running Twin & you will see a Hugh Difference!! Let me know what you find??

i don't know joe,i don't think they will work! maybe you should return them.

 

[aaron alberico]

Mr. Jim, let me tell you my thoughts.

I have played with a lot of different materials for making head buttons. Aluminum in 2024, 2011,4032, 2017, 6061, 7075, 7068 and more. Stainless steel 303. Alloy steels. 110 copper. 544 bronze and 360 brass.

From what I can tell, there is an optimum chamber temperature for horsepower and RPM on our nitro engines. Not too cool and not too hot.

With a water cooled head, using 360 brass for the head button material, I have found that is very close to maintaining this optimum combustion temp during a run. It even makes the water flow rate less sensitive.

With an air cooled head the 360 brass with not work because the heat dissipation rate is too slow. This allows the combustion chamber temps to run away causing the engine to detonate and this adds even more heat to the chamber. The aluminum alloys are much better in maintaining these optimum chamber temps with their higher heat flows.

When using aluminum for a head button even with regulating the water flow it is difficult to keep the chamber temps in the sweet spot temp as it is above 212 degrees, the boiling point of water. A pressurized system is then needed, adding to the complexity of our toys.

These are just my thoughts after playing with the different head button materials. What do you think?

Charles

Charles when we ran the river years ago with BIG BLOCK CHEVYS and Jet drive we looked for anything that would improve LOADED RPM. We found twin 200 HP Nitrous Plates on a Tunnel Ram intake on a 2 - 4 barrel set up was the ticket to add 3000-3500 loaded rpm. It was the Compressed Oxygen we were looking for & it took 3 times more fuel pressure to keep everything Happy while you were ON the Button.......... Most Nitro R/C Marine engines we run today are overcooled. Sometimes it is the application... it allows for the prop to unload & the engine & model is now traveling at a higher speed and the water flow increases too. Some engines are designed better to allow the engine to make a little more heat than the water flow can remove. But Most are Over cooling the way they come from the mfger. I`am sure you know now the advantages of Brass Head Buttons. To date for me........ It is the Best Performance Part that can be Put on a Boat R/C Engine. If someone is making one that is better? out of a different alloy? I would like to test it. We are running the same volume that worked with the alum head buttons. The volume has not been changed it is Only the Alloy making the difference. And the Big Engines have Picked up about 3000 Loaded RPM. & That is Hard to Find Normally!!!! I dont care what you change... I I got to say is BEEP BEEP!!!!!!!!

"And the Big Engines have Picked up about 3000 Loaded RPM."

3000 rpm would be good for at least 11 mph with the 1667's that you are using. Is that the speed increase that you have seen with the brass heads?

Andy I got the 1667 props today! Thanks Just in time for Hobart... Off corner speeds, thru the corner, and Wide Open Throttle is all better... I would say 7-10 mph. Now I believe different mfger and size engines will see different results & I have not changed anything about the flow of the water from the alum heads i was running earlier this year. You know we have traveled up and down the highways for several years changing props, pipes, fuel type and percentages, Boats Boat sponsons sponsons angles, set up & I have never seen a single part pick a engine up this much.. Maybe before we were blowing a large percentage of the unburn Nitro out the pipe? & the Higher more ideal heat of the prechamber now allows you to Light it?? The Lake is my Dyno. it is the Bottom line for what you have come Race Day. & I know what I`am seeing....... Take your best engine that you already know the performance curve on and Make a Brass Button for it & you let me know what you see.. I believe you will be looking for More Prop in just a few laps. Todays Newier Hydros run a Wider Air Gap between the boat and the surface of the water, most have narrower sponsons for less contact and drag, Todays Engines make Good Power....... Speed & Performance Still Sells!!!!!!!! I will say a Set of Brass Head Buttons will compliment a Good Running Twin & you will see a Hugh Difference!! Let me know what you find??

Joe

Your --- I would say 7-10mph gain...

Is that just a guess, or actual speed gain you have seen on radar gun?

and how are you getting the extra gain of 3000rpm reading from?... on board tacho... or Andy's theory of the RPM'S/speed x L.E pitch of prop?

As i could be keen on making some for my twin......

Thanks

 

[Ian Inverarity]

Have you ever seen steam or boiling water comming out of the H2O outlet?

Sure have, a few times this year trying to find out the lower limit to cooling my 45. Found the limit! Too hot is no good for power either.

 

[Jim Allen]

Mr. Jim, have you personally tried a 360 brass head button in comparison to an aluminum head button on a water cooled RC nitro boat engine running on your dyno or in your boat? If so, what were the results?

Charles Perdue

Mr Charles,

The answer is yes! Here is a partial list of some of the alloys that were tested before I realized that the material used, has little, if any effect, on preventing detonation in a chamber & on the piston crown. As Andy has already stated, not being able to see the detonation doesn't mean it is not there. Smaller size engines were always much less effected than larger size engines. However, the key factor in preventing detonation in head buttons & on piston crowns is not the alloy used.

The following is a partial list of alloys extensively tested, listed in random order:

2024-T351 aluminum

#390-A silicon aluminum

#360 free machining brass

RSA #431 silicon aluminum

Dispal #250 silicon aluminum

2017-T4 aluminum

4032-T651 silicon aluminum

Ampcoloy #940 nickel copper

1018 cold rolled steel

2618-T61 aluminum

2218-T72 aluminum

At some point, a mechanical engineer named Carl Dodge, explained to me that the shape of the head button & not the material it was made of, is the critical factor in preventing head button detonation. Carl, who beat the Russians in world level speed plane events, with his home made 42,000 RPM .21 engine, explained how he was using a cone shapped head that had no squish band.

I tested many head shapes; hemi types of various radii & depths, flat top hemis, trumphet types of various radii & depths, cones & double bubble hemi types. Many different compression ratios, many different maxium squish velocities, deck clearances, fuels, lubricants, head button cooling designs, etc. At the end of this lengthy process, the best head shape was the double bubble type hemi. It is still used on the Nelson .45 long stroke with the Nelson turbo plug.

I did not find any thing better until information was presented on the "TWOSTROKETECH" site. No individual, without invitation, can inter or read the information presented here, by 158 of the worlds most knowledgeable engineers who are building competitive high performance racing two cycle engines. The site does not come up on Google.

What they discovered eliminated detonation & holed piston crowns which are the same problems we are encountering. Even if the other things previously mentioned are not corrected, there will be a great improvment towards eliminating detonation.

To be continued.

Jim Allen

 

[Jim Allen]

In response to posts about coolant head temperatures, I have fouind the following to be true. "CHT, by itself, doesn't tell you much at all. The reason is because no two engines can be directly compared as the data gained is totally dependent upon the heat path to the plug, the plug heat range & the coolant circuit efficiency. What the CHT is good for, when used with the EGT, is that it's a excellent tuning tool, either by driver eye, or data logger.

When the engine is under its heaviest load, both CHT & EGT should keep rising, as load or RPM increase. As soon as the EGT levels off, or worse starts to drop, as the CHT keeps going up, you are starting to detonate. What happens next is of some value when only looking at CHT. When you have serious detonation, the plug temperature on the piezzo CHT transducer goes crazy & the temperature cannot be read. By then the piston is usually holed."

Jim Allen

 

[jaxracer]

This is an excellent discussion guys. But now let me bring up another variable for discussion, plug type. Wouldn't running a hotter plug achieve the same or similar desired effect of making the chamber hotter to burn more nitro? Wouldn't that in effect actually be more efficient and better on an engine than squeezing down the water because the hotter plug would concentrate the additional heat within the cylinder itself where the nitro needs to be burned and the water cooling would keep the overall engine temps (case, bearings, etc.) in check to help prevent engine failure due to heat? For instance running the hotter MC-59 plug instead of the MC-9?

Joe and Steve, what plugs are you having success running in the brass head buttons and have you tried hot plugs with them or does that generate too much heat and therefore translating to detonation in the chamber? And also, what nitro percentages are you guys running with these results?

-Mitch

 

[Charles Perdue]

Jim, with all of this "Secret Society" stuff that you are supposedly privy to, you saying that you are the only one right and everyone else is wrong, about the 360 brass head material not making a difference compared to aluminum even though a lot of boaters have tested it and are running it with better performance and you saying the cylinder head temperature does not make any difference in the performance of our boat engines even though that is a proven fact, and a lot of your other incorrect comments that I do not want to be associated with.

I am going to bow out with grace and leave you with your thread. Good luck with your venture.

Charles Perdue

Just one more question, what was the official speed that you ran with your X-hydro when you held the SAW record?

 

[Jack ODonnell]

Jim, with all of this "Secret Society" stuff that you are supposedly privy to, you saying that you are the only one right and everyone else is wrong, about the 360 brass head material not making a difference compared to aluminum even though a lot of boaters have tested it and are running it with better performance and you saying the cylinder head temperature does not make any difference in the performance of our boat engines even though that is a proven fact, and a lot of your other incorrect comments that I do not want to be associated with.

I am going to bow out with grace and leave you with your thread. Good luck with your venture.

Charles Perdue

Just one more question, what was the official speed that you ran with your X-hydro when you held the SAW record?

 

[Joe Warren]

Mr. Jim, let me tell you my thoughts.

I have played with a lot of different materials for making head buttons. Aluminum in 2024, 2011,4032, 2017, 6061, 7075, 7068 and more. Stainless steel 303. Alloy steels. 110 copper. 544 bronze and 360 brass.

From what I can tell, there is an optimum chamber temperature for horsepower and RPM on our nitro engines. Not too cool and not too hot.

With a water cooled head, using 360 brass for the head button material, I have found that is very close to maintaining this optimum combustion temp during a run. It even makes the water flow rate less sensitive.

With an air cooled head the 360 brass with not work because the heat dissipation rate is too slow. This allows the combustion chamber temps to run away causing the engine to detonate and this adds even more heat to the chamber. The aluminum alloys are much better in maintaining these optimum chamber temps with their higher heat flows.

When using aluminum for a head button even with regulating the water flow it is difficult to keep the chamber temps in the sweet spot temp as it is above 212 degrees, the boiling point of water. A pressurized system is then needed, adding to the complexity of our toys.

These are just my thoughts after playing with the different head button materials. What do you think?

Charles

Charles when we ran the river years ago with BIG BLOCK CHEVYS and Jet drive we looked for anything that would improve LOADED RPM. We found twin 200 HP Nitrous Plates on a Tunnel Ram intake on a 2 - 4 barrel set up was the ticket to add 3000-3500 loaded rpm. It was the Compressed Oxygen we were looking for & it took 3 times more fuel pressure to keep everything Happy while you were ON the Button.......... Most Nitro R/C Marine engines we run today are overcooled. Sometimes it is the application... it allows for the prop to unload & the engine & model is now traveling at a higher speed and the water flow increases too. Some engines are designed better to allow the engine to make a little more heat than the water flow can remove. But Most are Over cooling the way they come from the mfger. I`am sure you know now the advantages of Brass Head Buttons. To date for me........ It is the Best Performance Part that can be Put on a Boat R/C Engine. If someone is making one that is better? out of a different alloy? I would like to test it. We are running the same volume that worked with the alum head buttons. The volume has not been changed it is Only the Alloy making the difference. And the Big Engines have Picked up about 3000 Loaded RPM. & That is Hard to Find Normally!!!! I dont care what you change... I I got to say is BEEP BEEP!!!!!!!!

"And the Big Engines have Picked up about 3000 Loaded RPM."

3000 rpm would be good for at least 11 mph with the 1667's that you are using. Is that the speed increase that you have seen with the brass heads?

Andy I got the 1667 props today! Thanks Just in time for Hobart... Off corner speeds, thru the corner, and Wide Open Throttle is all better... I would say 7-10 mph. Now I believe different mfger and size engines will see different results & I have not changed anything about the flow of the water from the alum heads i was running earlier this year. You know we have traveled up and down the highways for several years changing props, pipes, fuel type and percentages, Boats Boat sponsons sponsons angles, set up & I have never seen a single part pick a engine up this much.. Maybe before we were blowing a large percentage of the unburn Nitro out the pipe? & the Higher more ideal heat of the prechamber now allows you to Light it?? The Lake is my Dyno. it is the Bottom line for what you have come Race Day. & I know what I`am seeing....... Take your best engine that you already know the performance curve on and Make a Brass Button for it & you let me know what you see.. I believe you will be looking for More Prop in just a few laps. Todays Newier Hydros run a Wider Air Gap between the boat and the surface of the water, most have narrower sponsons for less contact and drag, Todays Engines make Good Power....... Speed & Performance Still Sells!!!!!!!! I will say a Set of Brass Head Buttons will compliment a Good Running Twin & you will see a Hugh Difference!! Let me know what you find??

i don't know joe,i don't think they will work! maybe you should return them.

:lol: :lol: :lol: B) B)

 

[Joe Warren]

I am quite sure we will be talking about this topic for a while.... Some Maybe ordering some 360 material and Cutting themselves? Others maybe buying from Steve or whoever is willing to make them? We were going to talk about this later in the year But THE CAT IS OUT OF THE BAG!!!!!!

 

[dwilfong]

I am quite sure we will be talking about this topic for a while.... Some Maybe ordering some 360 material and Cutting themselves? Others maybe buying from Steve or whoever is willing to make them? We were going to talk about this later in the year But THE CAT IS OUT OF THE BAG!!!!!!

The cat was let out over two years ago but no one would listen.

Glad to see you all finely saw the light.

Here is a pic of my first one in May 2010. This was designed by Marty Davis who then showed me how to make it in the garage shop.

Amazing what comes out of a garage.

Thought it a honer when John Otto was pitting for Gene Mongar and turned to me and asked

"what makes that boat so dam fast"

David

 

[Jim Allen]

Jim, with all of this "Secret Society" stuff that you are supposedly privy to, you saying that you are the only one right and everyone else is wrong, about the 360 brass head material not making a difference compared to aluminum even though a lot of boaters have tested it and are running it with better performance and you saying the cylinder head temperature does not make any difference in the performance of our boat engines even though that is a proven fact, and a lot of your other incorrect comments that I do not want to be associated with.

I am going to bow out with grace and leave you with your thread. Good luck with your venture.

Charles Perdue

Just one more question, what was the official speed that you ran with your X-hydro when you held the SAW record?

Sorry to see you go, not really! I have NAMBA record sheets all the way back to 1985 & IMPBA sheets back to 1996. I don't see your name listed for any event what so ever. Maybe you ran some with some other organization. The last time I ran straight away in 1994 at a sanctioned NAMBA event, the official speed was 85.88. The boat was a 14 lb modified crapshooter with my engine & prop.

Jim Allen

 

[Joe Warren]

I am quite sure we will be talking about this topic for a while.... Some Maybe ordering some 360 material and Cutting themselves? Others maybe buying from Steve or whoever is willing to make them? We were going to talk about this later in the year But THE CAT IS OUT OF THE BAG!!!!!!

The cat was let out over two years ago but no one would listen.

Glad to see you all finely saw the light.

Here is a pic of my first one in May 2010. This was designed by Marty Davis who then showed me how to make it in the garage shop.

Amazing what comes out of a garage.

Thought it a honer when John Otto was pitting for Gene Mongar and turned to me and asked

"what makes that boat so dam fast"

David

Yes I know Marty was talking about them about 3 years ago in Charleston SC & I think different motors will see different results? But all will step up to More Performance with the extra pre-chamber heat. I`am sure Andy will be right back with some Big Results. Now I dont make them & I have nothing for sale. But I will have them on every motor I run as soon as I can get them all made If Steve is willing to make them...... I just received a Set of Brass buttons for a Set of VAC91 Twin engines

 

[dwilfong]

I am quite sure we will be talking about this topic for a while.... Some Maybe ordering some 360 material and Cutting themselves? Others maybe buying from Steve or whoever is willing to make them? We were going to talk about this later in the year But THE CAT IS OUT OF THE BAG!!!!!!

The cat was let out over two years ago but no one would listen.

Glad to see you all finely saw the light.

Here is a pic of my first one in May 2010. This was designed by Marty Davis who then showed me how to make it in the garage shop.

Amazing what comes out of a garage.

Thought it a honer when John Otto was pitting for Gene Mongar and turned to me and asked

"what makes that boat so dam fast"

David

Yes I know Marty was talking about them about 3 years ago in Charleston SC & I think different motors will see different results? But all will step up to More Performance with the extra pre-chamber heat.

I run them in all my engs .21 .45 .91 1.01 and one will be in the new VAC 1.05

All have benifited from this.

Now if you just make the chamber like in the pic.