41 Falcon cat build
11-09-2008, 09:50 PM
#252
Banned
Join Date: Jul 2008
Location: henderson, NV
Posts: 900
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
ORIGINAL: Performance Unlimited
The black cat runs a steady 67mph & 60 in the turns. It looks faster due to the zoom in on the video. The Falcon reaches the speed 3/4's down the straights ....running Octura 1475 B,S, Pitched 5.5 with cup. The black cat is an AC boats hull ..I know it is a wild thing with no fear except those on the lake......unpredictable at time with cross winds and waves. The Flcon is very stable up to 65mph, then it wants to blow over. I had to put small winglets on the front sponsons and now with zero trim you can actually see the bow level out and the boat accellerate. On the lake that thie boats were filmed it needs to be longer........LOL
The black cat runs a steady 67mph & 60 in the turns. It looks faster due to the zoom in on the video. The Falcon reaches the speed 3/4's down the straights ....running Octura 1475 B,S, Pitched 5.5 with cup. The black cat is an AC boats hull ..I know it is a wild thing with no fear except those on the lake......unpredictable at time with cross winds and waves. The Flcon is very stable up to 65mph, then it wants to blow over. I had to put small winglets on the front sponsons and now with zero trim you can actually see the bow level out and the boat accellerate. On the lake that thie boats were filmed it needs to be longer........LOL
11-09-2008, 10:28 PM
#258
Join Date: Nov 2008
Location: Largo, FL
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
Falcon CG 14" forward of the transom. Fuel bag located at CG point.
The winglets are the Nylon tail skids for r/c airplanes that are a tail dragger. Drilled one hole angled at 40 degrees down and bond them on with Automotive Goop.
The pic of the Falcon are with out the winglets and the boat gets a hig attitudewith no trim....wants to be a boat-plane. The video shows a lower attitude and the boat went from 65 to over 70 mph with out blow over...with zero trim of drive strut.
The winglets are the Nylon tail skids for r/c airplanes that are a tail dragger. Drilled one hole angled at 40 degrees down and bond them on with Automotive Goop.
The pic of the Falcon are with out the winglets and the boat gets a hig attitudewith no trim....wants to be a boat-plane. The video shows a lower attitude and the boat went from 65 to over 70 mph with out blow over...with zero trim of drive strut.
11-09-2008, 10:31 PM
#259
Join Date: Nov 2008
Location: Largo, FL
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
Falcon CG 14" forward of the transom. Fuel bag located at CG point.
The winglets are the Nylon tail skids for r/c airplanes that are a tail dragger. Drilled one hole angled at 40 degrees down and bond them on with Automotive Goop.
The pic of the Falcon are with out the winglets and the boat gets a hig attitudewith no trim....wants to be a boat-plane. The video shows a lower attitude and the boat went from 65 to over 70 mph with out blow over...with zero trim of drive strut.
The winglets are the Nylon tail skids for r/c airplanes that are a tail dragger. Drilled one hole angled at 40 degrees down and bond them on with Automotive Goop.
The pic of the Falcon are with out the winglets and the boat gets a hig attitudewith no trim....wants to be a boat-plane. The video shows a lower attitude and the boat went from 65 to over 70 mph with out blow over...with zero trim of drive strut.
11-09-2008, 10:44 PM
#260
Senior Member
Thread Starter
Join Date: Jul 2008
Location: , MO
Posts: 690
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
Your CG needs to be a % number 14 inches from transom does not tell me much sounds like its a plane because the CG was too low to run that fast.
Jake
Jake
11-09-2008, 11:01 PM
#262
Senior Member
Thread Starter
Join Date: Jul 2008
Location: , MO
Posts: 690
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
In the video of my cat it allso has no positive trim it has a slight bit of negitive trim that is why you see it slap then blow over.It was rocking a bit there was allso leaves on that side of the pond the wind was allso blowing the prop is very agressive ect its a fine line LOL.Be for the video was taken I ran it and it poped up then slamed down brought it in and leaves were stuck to the skeg and rudder drag mabey ha ha.
Jake
Jake
11-09-2008, 11:43 PM
#264
Senior Member
Thread Starter
Join Date: Jul 2008
Location: , MO
Posts: 690
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
ORIGINAL: lawnmower man
what engine is that making 7.74 hp@12000 that is brutal
what engine is that making 7.74 hp@12000 that is brutal
Not saying his motor is no good but becarefull of dyno sheets.
Jake
11-10-2008, 06:28 AM
#265
Join Date: Nov 2008
Location: Largo, FL
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
CG is 32% of the lenght..14 inches from the transom.
Dyno Correction Factor and Relative Horsepower
So what's all this correction factor stuff anyway??
The horsepower and torque available from a normally aspirated internal combustion engine are dependent upon the density of the air... higher density means more oxygen molecules and more power... lower density means less oxygen and less power.
The relative horsepower, and the dyno correction factor, allow mathematical calculation of the affects of air density on the wide-open-throttle horsepower and torque. The dyno correction factor is simply the mathematical reciprocal of the relative horsepower value.
Originally, all of the major US auto manufacturers were in or around Detroit Michigan, and the dyno reading taken in Detroit were considered to be the standard. However, as the auto industry spread both across the country and around the globe, the auto manufacturers needed a way to correlate the horsepower/torque data taken at those "non-standard" locations with the data taken at the "standard" location. Therefore, the SAE created J1349 in order to convert (or "correct") the dyno data taken in, for example, California or in Tokyo to be as if the data had been taken at standard conditions in Detroit.
What's it good for?
One common use of the dyno correction factor is to standardize the horsepower and torque readings, so that the effects of the ambient temperature and pressure are removed from the readings. By using the dyno correction factor, power and torque readings can be directly compared to the readings taken on some other day, or even taken at some other altitude.
That is, the corrected readings are the same as the result that you would get by taking the car (or engine) to a certain temperature controlled, humidity controlled, pressure controlled dyno shop where they measure "standard" power, based on the carefully controlled temperature, humidity and pressure.
If you take your car to the dyno on a cold day at low altitude, it will make a lot of power. And if you take exactly the same car back to the same dyno on a hot day, it will make less power. But if you take the exact same car to the "standard" dyno (where the temperature, humidity and pressure are all carefully controlled) on those different days, it will always make exactly the same power.
Sometimes you may want to know how much power you are really making on that specific day due to the temperature, humidity and pressure on that day; in that case, you should look at the uncorrected power readings.
But when you want to see how much more power you have solely due to the new headers, or the new cam, then you will find that the corrected power is more useful, since it removes the effects of the temperature, humidity and atmospheric pressure and just shows you how much more (or less) power you have than in your previous tests.
There is no "right" answer... it's simply a matter of how you want to use the information.
If you want to know whether you are going to burn up the tranny with too much power on a cool, humid day, then go to the dyno and look at uncorrected power to see how exactly much power you have under these conditions.
But if you want to compare the effects due to modifications, or you want to compare several different cars at different times, then the corrected readings of the "standard" dyno will be more useful.
How's it calculated?
The Society of Automotive Engineers (SAE) has created a standard method for correcting horsepower and torque readings so that they will seem as if the readings had all been taken at the same "standard" test cell where the air pressure, humidity and air temperature are held constant. Furthermore, the standard includes an assumed mechanical efficiency of 85% in order to provide an estimate of the true engine horsepower (without accessories).
The relative horsepower is simply the mathematical reciprocal of the correction factor.
SAE J1349 Update:
In August 2004 the SAE released J1349 Revised AUG2004 which specifies that the preferred method of determining the friction power used by the motor accessories is actual measurement, and that the assumption of 85% mechanical efficiency (as formerly used in SAE J1349 Revision JUN90) should only be used when actual friction data are not available.
The AUG2004 revision also makes it clear that this correction factor is not intended to provide accurate corrections over an extremely wide range, but rather that the intended range of air temperatures is 15 to 35 deg C, and the intended range of dry air pressures is 900 to 1050 mb.
Horsepower and Torque:
Power is the rate at which work is done. When the engine torque is turning the crankshaft and power is being delivered, the resulting horsepower will increase.
. Basically if you can keep the same amount of torque, then the more rpm you can turn, the more horsepower you get!
That's why Formula One and CART and IRL engines all turn incredible rpm. The faster the engine turns, the more power it can make (when it's properly tuned to operate at that speed).
It is sort of humorous that the NASCAR CUP cars all have strictly defined aerodynamics, strictly defined engine displacement, even strictly defined carburetors... but no limitation on RPM, and hence no limit on horsepower (since power is highly dependent upon engine RPM, as shown above).
Consider for example: a normally aspirated internal combustion engine typically produces about 1 to 1.5 ft-lbs of torque per cubic inch when it is properly tuned to operate at any specific rpm. With a 2 liter (about 122 cubic inches) engine, producing 1.5 ft-lbs of torque per cubic inch, you would expect to get about 180 hp at 5200 rpm... but you will get a whopping 415 hp if you can get it to run at 12,000 rpm.
The 3.5 liter IRL engine is reported to produce about 650 hp at 10,700 rpm. That would be about 1.5 ft-lbs per cubic inch.
The Ferrari 3.0 liter Formula One engine is rumored to produce about 860 hp at 18,500 rpm. That would be about 1.33 ft-lbs per cubic inch.
Frankly I suspect that these ridiculous RPM values are one of the reasons that CART, IRL and F1 racing are so poorly received here in the USA. People want to see and hear race cars that they can identify with, cars that have something in common with the spectator's own cars, not these silly motors that sound like enraged hornets. And if NASCAR fails to specify some reasonable RPM limits, they too may be doomed to the same fate.
And at the other end of the rpm spectrum, one model of the 360 cubic inch four cylinder Lycoming IO-360 aircraft engine produces 180 hp at 2700 rpm, which is 0.97 ft-lbs per cubic inch.
In general, production automobile engines that have a broad torque band will produce about 0.9 to 1.1 ft-lbs per cubic inch. Highly tuned production engines, such as the Honda S2000 or the Ferrari F50 are in the range of 1.1 to 1.3 ft-lbs per cubic inch. Highly tuned race engines such as NASCAR, IRL and Formula One are often in the range of 1.3 to 1.5 ft-lbs per cubic inch.
Dyno Correction Factor and Relative Horsepower
So what's all this correction factor stuff anyway??
The horsepower and torque available from a normally aspirated internal combustion engine are dependent upon the density of the air... higher density means more oxygen molecules and more power... lower density means less oxygen and less power.
The relative horsepower, and the dyno correction factor, allow mathematical calculation of the affects of air density on the wide-open-throttle horsepower and torque. The dyno correction factor is simply the mathematical reciprocal of the relative horsepower value.
Originally, all of the major US auto manufacturers were in or around Detroit Michigan, and the dyno reading taken in Detroit were considered to be the standard. However, as the auto industry spread both across the country and around the globe, the auto manufacturers needed a way to correlate the horsepower/torque data taken at those "non-standard" locations with the data taken at the "standard" location. Therefore, the SAE created J1349 in order to convert (or "correct") the dyno data taken in, for example, California or in Tokyo to be as if the data had been taken at standard conditions in Detroit.
What's it good for?
One common use of the dyno correction factor is to standardize the horsepower and torque readings, so that the effects of the ambient temperature and pressure are removed from the readings. By using the dyno correction factor, power and torque readings can be directly compared to the readings taken on some other day, or even taken at some other altitude.
That is, the corrected readings are the same as the result that you would get by taking the car (or engine) to a certain temperature controlled, humidity controlled, pressure controlled dyno shop where they measure "standard" power, based on the carefully controlled temperature, humidity and pressure.
If you take your car to the dyno on a cold day at low altitude, it will make a lot of power. And if you take exactly the same car back to the same dyno on a hot day, it will make less power. But if you take the exact same car to the "standard" dyno (where the temperature, humidity and pressure are all carefully controlled) on those different days, it will always make exactly the same power.
Sometimes you may want to know how much power you are really making on that specific day due to the temperature, humidity and pressure on that day; in that case, you should look at the uncorrected power readings.
But when you want to see how much more power you have solely due to the new headers, or the new cam, then you will find that the corrected power is more useful, since it removes the effects of the temperature, humidity and atmospheric pressure and just shows you how much more (or less) power you have than in your previous tests.
There is no "right" answer... it's simply a matter of how you want to use the information.
If you want to know whether you are going to burn up the tranny with too much power on a cool, humid day, then go to the dyno and look at uncorrected power to see how exactly much power you have under these conditions.
But if you want to compare the effects due to modifications, or you want to compare several different cars at different times, then the corrected readings of the "standard" dyno will be more useful.
How's it calculated?
The Society of Automotive Engineers (SAE) has created a standard method for correcting horsepower and torque readings so that they will seem as if the readings had all been taken at the same "standard" test cell where the air pressure, humidity and air temperature are held constant. Furthermore, the standard includes an assumed mechanical efficiency of 85% in order to provide an estimate of the true engine horsepower (without accessories).
The relative horsepower is simply the mathematical reciprocal of the correction factor.
SAE J1349 Update:
In August 2004 the SAE released J1349 Revised AUG2004 which specifies that the preferred method of determining the friction power used by the motor accessories is actual measurement, and that the assumption of 85% mechanical efficiency (as formerly used in SAE J1349 Revision JUN90) should only be used when actual friction data are not available.
The AUG2004 revision also makes it clear that this correction factor is not intended to provide accurate corrections over an extremely wide range, but rather that the intended range of air temperatures is 15 to 35 deg C, and the intended range of dry air pressures is 900 to 1050 mb.
Horsepower and Torque:
Power is the rate at which work is done. When the engine torque is turning the crankshaft and power is being delivered, the resulting horsepower will increase.
. Basically if you can keep the same amount of torque, then the more rpm you can turn, the more horsepower you get!
That's why Formula One and CART and IRL engines all turn incredible rpm. The faster the engine turns, the more power it can make (when it's properly tuned to operate at that speed).
It is sort of humorous that the NASCAR CUP cars all have strictly defined aerodynamics, strictly defined engine displacement, even strictly defined carburetors... but no limitation on RPM, and hence no limit on horsepower (since power is highly dependent upon engine RPM, as shown above).
Consider for example: a normally aspirated internal combustion engine typically produces about 1 to 1.5 ft-lbs of torque per cubic inch when it is properly tuned to operate at any specific rpm. With a 2 liter (about 122 cubic inches) engine, producing 1.5 ft-lbs of torque per cubic inch, you would expect to get about 180 hp at 5200 rpm... but you will get a whopping 415 hp if you can get it to run at 12,000 rpm.
The 3.5 liter IRL engine is reported to produce about 650 hp at 10,700 rpm. That would be about 1.5 ft-lbs per cubic inch.
The Ferrari 3.0 liter Formula One engine is rumored to produce about 860 hp at 18,500 rpm. That would be about 1.33 ft-lbs per cubic inch.
Frankly I suspect that these ridiculous RPM values are one of the reasons that CART, IRL and F1 racing are so poorly received here in the USA. People want to see and hear race cars that they can identify with, cars that have something in common with the spectator's own cars, not these silly motors that sound like enraged hornets. And if NASCAR fails to specify some reasonable RPM limits, they too may be doomed to the same fate.
And at the other end of the rpm spectrum, one model of the 360 cubic inch four cylinder Lycoming IO-360 aircraft engine produces 180 hp at 2700 rpm, which is 0.97 ft-lbs per cubic inch.
In general, production automobile engines that have a broad torque band will produce about 0.9 to 1.1 ft-lbs per cubic inch. Highly tuned production engines, such as the Honda S2000 or the Ferrari F50 are in the range of 1.1 to 1.3 ft-lbs per cubic inch. Highly tuned race engines such as NASCAR, IRL and Formula One are often in the range of 1.3 to 1.5 ft-lbs per cubic inch.
11-10-2008, 08:11 AM
#266
Senior Member
Thread Starter
Join Date: Jul 2008
Location: , MO
Posts: 690
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
Please do not promote you motor on my thread anymore you want to talk about your Falcon great. Lets see some pics of it please no more dyno info its just not revelent to this thread.
Thanks Jake
Thanks Jake
11-10-2008, 09:33 AM
#269
RE: 41 Falcon cat build
ORIGINAL: JakeDW
Please do not promote you motor on my thread anymore you want to talk about your Falcon great. Lets see some pics of it please no more dyno info its just not revelent to this thread.
Thanks Jake
Please do not promote you motor on my thread anymore you want to talk about your Falcon great. Lets see some pics of it please no more dyno info its just not revelent to this thread.
Thanks Jake
As far as Performance Unlimited goes, it seems like he forgot to read the site rules as in his signature he is supposed to state that he is the owner of that company as are all manufacturers/distributors of an RC related product.
Being the former boat Mod in here I know the rules inside-out and sideways.
PLEASE, let's get back to typing about Falcon 41's.
11-10-2008, 04:02 PM
#270
Senior Member
Thread Starter
Join Date: Jul 2008
Location: , MO
Posts: 690
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
ORIGINAL: Ron Olson
I hate to tell you this but the thread is really the property of RCU although you started it.
As far as Performance Unlimited goes, it seems like he forgot to read the site rules as in his signature he is supposed to state that he is the owner of that company as are all manufacturers/distributors of an RC related product.
Being the former boat Mod in here I know the rules inside-out and sideways.
PLEASE, let's get back to typing about Falcon 41's.
ORIGINAL: JakeDW
Please do not promote you motor on my thread anymore you want to talk about your Falcon great. Lets see some pics of it please no more dyno info its just not revelent to this thread.
Thanks Jake
Please do not promote you motor on my thread anymore you want to talk about your Falcon great. Lets see some pics of it please no more dyno info its just not revelent to this thread.
Thanks Jake
As far as Performance Unlimited goes, it seems like he forgot to read the site rules as in his signature he is supposed to state that he is the owner of that company as are all manufacturers/distributors of an RC related product.
Being the former boat Mod in here I know the rules inside-out and sideways.
PLEASE, let's get back to typing about Falcon 41's.
thanks guys I am out Jake
11-10-2008, 04:34 PM
#271
Banned
Join Date: Jul 2008
Location: henderson, NV
Posts: 900
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
ORIGINAL: JakeDW
I hate to tell you this do you really think I thought I owned the thread it was an atempt to get back on subject though I did start the thread about info on my boat I guess I could go back and erase all my post.Mabey you should become a mod agine?
thanks guys I am out Jake
I hate to tell you this do you really think I thought I owned the thread it was an atempt to get back on subject though I did start the thread about info on my boat I guess I could go back and erase all my post.Mabey you should become a mod agine?
thanks guys I am out Jake
11-11-2008, 07:22 PM
#272
Banned
Join Date: Jul 2008
Location: henderson, NV
Posts: 900
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
ORIGINAL: JakeDW
Your CG needs to be a % number 14 inches from transom does not tell me much sounds like its a plane because the CG was too low to run that fast.
Jake
Your CG needs to be a % number 14 inches from transom does not tell me much sounds like its a plane because the CG was too low to run that fast.
Jake
11-11-2008, 08:06 PM
#273
Join Date: Nov 2008
Location: Largo, FL
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
Cats are funny on getting them set up...I just need a bigger lake that is longer than 100 yards. The stryker is more stable in rough waters and wind. Although there is a long or should I say a very large lake 1hr away...needs to be a calm day for high speeds.
The strut on my Falcon I made from stainless and it uses needle bearings ...Oil it after every run and they have lasted 8 months now compared to worn out bushings and the small ball bearings that are usually used and last about 2 tanks or so.
That CG is probally in a good spot. If the boat is too heavy no top speed and if it is too light it won't settle and either bounces on small waves or blows over easily.
The strut on my Falcon I made from stainless and it uses needle bearings ...Oil it after every run and they have lasted 8 months now compared to worn out bushings and the small ball bearings that are usually used and last about 2 tanks or so.
That CG is probally in a good spot. If the boat is too heavy no top speed and if it is too light it won't settle and either bounces on small waves or blows over easily.
11-11-2008, 08:30 PM
#274
Banned
Join Date: Jul 2008
Location: henderson, NV
Posts: 900
Likes: 0
Received 0 Likes
on
0 Posts
RE: 41 Falcon cat build
My prop is a ABC 2716 20* rake, it is flighty but the speed is really good, tried many props on this cat and ended up with it so far, I know when the cat nose down would lost a bit of top speed but it's better whan it runs like a kite...LOL