For heaven's sake don't break this work of art trying to get 300 hp! That would be a real tragedy after all the work you put into it.
I, for one, and damn impressed and would love to see her run on the water.
Jeff
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For heaven's sake don't break this work of art trying to get 300 hp! That would be a real tragedy after all the work you put into it.
I, for one, and damn impressed and would love to see her run on the water.
Jeff
Well said gentlemen!
I would also suggest to optimize the motor and stay away from the full potential 10000 rpm. Yes - drag racers exceed that number, but these are V6s and I really wonder how long the precious Mercury "gold" rings last.
Mr Austin: congratulations for achieving this significant milestone in the lofty world of designing and building this one of a exotic kind beast.
Your fuel consumption numbers are no less impressive: a gallon a minute corresponds to the crossflow Twister II consumption with only some 170hp, as well as the Mercury 2.5 ROS (280XS) with some 280 to 300hp. (I own one - not yet raced - waiting for my STV to come back from the epoxy shop - and yes I am a 70 years old fool).
The next problem will be to find a lower unit which will stay together with the wind-up and let go of the 6 il crank.
Good luck and kind regards, Wolfgang.
Mr Austin maybe I wrote it wrong. My intent was purely complementary and I believe what you post. That's whats wrong with the written word, You can`t see the persons excitement when he speaks. I am in awe of your project and have been from the start and certainly mint no disrespect at all. What you have built and what it has done as well as what it will do is extremely impressive. I guess if I`m guilty of something it would be thinking out loud.
DB
Any gustimate on the parasitic loss from the chain and associated dyno stuff? You may be closer to 300 than you think!
OT: When you say 'Beast', I think of The Beast of Turin.
Four cylinders, 28.5 liters, 1900 RPM, and about the same HP as you're getting.
https://www.youtube.com/watch?v=0TV2l6TOuGA
Very valid point you are stating here - losses could well be 10 to 15%. What temperature is the oil running at? Is there a defoamer in the oil tank? On the water dynos we used massive surface cooling towers for the water, which could get quite warm when running full load (no computer dynos in the `60s and `70s).
Rgds, Wolfgang
where is the load cell, on the pump or reduction?
I guess that the question of how much parasitic drag there may have been from the dyno is now a real consideration. The issue with the chain failure is because the double row chain sprocket on the driven shaft was not sufficient for the double row heavy duty chain. There were no disclaimers associated with the sprocket specs but it is not a fit. When I initially set up the chain I realized that the chain fit snug but did not realize that the chain was not bottoming in the sprocket roller pockets. I had ordered a heavy duty pre-stressed chain as a replacement only to be disappointed when received and realized that I had received a standard pre-stressed chain. When I installed the original HD chain, I had to shorten by four or five links. I took the new standard chain and laid in a spare sprocket to see how it looked and then took the left over HD chain and tried in the sprocket and realized how tight it felt. I took the links and drove them down into the sprocket. I could pick the sprocket up by just gripping the chain.
Attachment 63131
I then went back to the failed chain and reexamined it looking at the area that would have been pinched by the lack of space between the two sprocket rows of teeth. As can be seen in the pictures that the chain center section links are burned brown and that the link segments adjacent to the teeth are pressure marked from being pinched. All of this heat energy of pulling the chain into and out of the sprocket and coming from the driven sprocket is energy that is not making it to the load sensor at the pump.
Attachment 63132
Attachment 63133
Attachment 63134
The last 2 pics are of the drive and driven sprockets after I changed to the chain drive. You can see in the drive sprocket that the links are tight between the teeth and there is room at the outer sides of the teeth. The driven sprocket I welded from flat sprockets and my turned hub. Dual sprockets that large are not offered and need to be fabricated. That sprocket was welded with the HD chain as a spacing guide and can be seen in the picture that it has the right center to center spacing.
Attachment 63135
Attachment 63136
I guess that the question of how much parasitic drag there may have been from the dyno is now a real consideration. The issue with the chain failure is because the double row chain sprocket on the driven shaft was not sufficient for the double row heavy duty chain. There were no disclaimers associated with the sprocket specs but it is not a fit. When I initially set up the chain I realized that the chain fit snug but did not realize that the chain was not bottoming in the sprocket roller pockets. I had ordered a heavy duty pre-stressed chain as a replacement only to be disappointed when received and realized that I had received a standard pre-stressed chain. When I installed the original HD chain, I had to shorten by four or five links. I took the new standard chain and laid in a spare sprocket to see how it looked and then took the left over HD chain and tried in the sprocket and realized how tight it felt. I took the links and drove them down into the sprocket. I could pick the sprocket up by just gripping the chain.
Attachment 63131
I then went back to the failed chain and reexamined it looking at the area that would have been pinched by the lack of space between the two sprocket rows of teeth. As can be seen in the pictures that the chain center section links are burned brown and that the link segments adjacent to the teeth are pressure marked from being pinched. All of this heat energy of pulling the chain into and out of the sprocket and coming from the driven sprocket is energy that is not making it to the load sensor at the pump.
Attachment 63132
Attachment 63133
Attachment 63134
The last 2 pics are of the drive and driven sprockets after I changed to the chain drive. You can see in the drive sprocket that the links are tight between the teeth and there is room at the outer sides of the teeth. The driven sprocket I welded from flat sprockets and my turned hub. Dual sprockets that large are not offered and need to be fabricated. That sprocket was welded with the HD chain as a spacing guide and can be seen in the picture that it has the right center to center spacing.
Attachment 63137
Attachment 63138
I guess that the question of how much parasitic drag there may have been from the dyno is now a real consideration. The issue with the chain failure is because the double row chain sprocket tooth center to center spacing on the drive shaft was not sufficient for the double row heavy duty chain. There were no disclaimers associated with the sprocket specs but it is not a fit. When I initially set up the chain I realized that the chain fit snug but did not realize that the chain was not bottoming in the sprocket roller pockets. I had ordered a heavy duty pre-stressed chain as a replacement only to be disappointed when received and realized that I had received a standard pre-stressed chain. When I installed the original HD chain, I had to shorten by four or five links. I took the new standard chain and laid in a spare sprocket to see how it looked and then took the left over HD chain and tried in the sprocket and realized how tight it felt. I took the links and drove them down into the sprocket. I could pick the sprocket up by just gripping the chain.
Attachment 63139
I then went back to the failed chain and reexamined it looking at the area that would have been pinched by the lack of space between the two sprocket rows of teeth. As can be seen in the pictures that the chain center section links are burned brown and that the link segments adjacent to the teeth are pressure marked from being pinched. All of this heat energy of pulling the chain into and out of the sprocket and coming from the drive sprocket is energy that is not making it to the load sensor at the pump.
Attachment 63140
Attachment 63141
Attachment 63142
The last 2 pics are of the drive and driven sprockets after I changed to the chain drive. You can see in the drive sprocket that the links are tight between the teeth and there is room at the outer sides of the teeth. The driven sprocket I welded from flat sprockets and my turned hub. Dual sprockets that large are not offered and need to be fabricated. That sprocket was welded with the HD chain as a spacing guide and can be seen in the picture that it has the right center to center spacing.
Attachment 63143
Attachment 63144
Perhaps one of those onshaft inline eddy current load cells might be an easier way to measure the output.
They used them on one European offshore sterndrive class to allow a power to weight specification to be met so I know they are small.