CGT wrote: ↑Thu May 17, 2018 2:11 pm
Over the years, studying the effects of cam positioning on my own and others dyno tests has led me to looking at valve events on a more individual basis rather than Lobe Separation...or at least trying to. Post's from ST members that were and are involved with DOHC engines doing positioning tests was also very inciteful to me.
There are some very interesting things being done with the Coyote engine...and others I'm sure, as far as playing with the camshaft actuators via software, in relation to rpm etc. as well. Want a lumpy idle in your Coyote? No problem..how does an instant 96 LSA at idle only sound to ya. There is definitely not one set of centerlines that are ideal through a broad rpm range.
Too many adjustments for my brain to deal with, it would probably get me in trouble.
If memory serves me right the one I saw ran a 106 through the meat of the pull moving to a 109 and ending with a 113... It might have been Jon that posted it years ago.
Couldn't be, he knows nothing! Lol
In all seriousness, the events are what you need to focus on to take it to the next level.
Everything else is just a byproduct.
CGT wrote: ↑Thu May 17, 2018 2:11 pm
Over the years, studying the effects of cam positioning on my own and others dyno tests has led me to looking at valve events on a more individual basis rather than Lobe Separation...or at least trying to. Post's from ST members that were and are involved with DOHC engines doing positioning tests was also very inciteful to me.
There are some very interesting things being done with the Coyote engine...and others I'm sure, as far as playing with the camshaft actuators via software, in relation to rpm etc. as well. Want a lumpy idle in your Coyote? No problem..how does an instant 96 LSA at idle only sound to ya. There is definitely not one set of centerlines that are ideal through a broad rpm range.
Too many adjustments for my brain to deal with, it would probably get me in trouble.
If memory serves me right the one I saw ran a 106 through the meat of the pull moving to a 109 and ending with a 113... It might have been Jon that posted it years ago.
Couldn't be, he knows nothing! Lol
In all seriousness, the events are what you need to focus on to take it to the next level. Everything else is just a byproduct.
Some see the events as a byproduct but we have been through this. Does it really matter at the end of the day if you end up with the same cam?
Would the others be wrong for saying your method is incorrect because you don't start with LSA and Overlap?
Oddly enough the second group would not say you are wrong they would be interested in learning how you do it.
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
GARY C wrote: ↑Thu May 17, 2018 5:38 pm...I really thought a lot of the factory engines would have moved away from cams by now but I guess the technology didn't advance as was predicted....Have you ever found engmod4t's predictions to match dyno results?
I met a guy at the Sonoma CA track in 1986 who was working on solenoid-operated valves. He figured his system would be fully operational in about two years. The plates on his Thunderbird read "EVA", for Electronic Valve Actuation...
I read a write up on an auto manufacture doing testing where they thought it would be the wave of the future, no starter, close the valves, shoot a shot of fuel in and fire the engine, it may have been Honda but it sounded like testing was in the process but i have also read where heat, oil and weight maybe part of the problem.
Maybe some more advanced in the actual research can shed light on it.
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
GARY C wrote: ↑Thu May 17, 2018 10:36 pm
I read a write up on an auto manufacture doing testing where they thought it would be the wave of the future, no starter, close the valves, shoot a shot of fuel in and fire the engine, it may have been Honda but it sounded like testing was in the process but i have also read where heat, oil and weight maybe part of the problem.
Maybe some more advanced in the actual research can shed light on it.
Just do the math, the energy required to accelerate the valves is a lot to ask from an electric drive.
The position control speed required follow a cam curve is multiples faster than the fastest CNC machines (although the valves would have much less weight, still the position computation and control is a limitation of CNCs).
The cost of one servo system to control one valve would be multiples of a cam and valvetrain.
NOT! I am sure you understand pressure deferential. To see the full 14.69 psi you would need absolute zero pressure / psi in the cylinder.
Also just what is the atmospheric pressure in the room when you are flowing the heads?
What does the pressure deferential on a running look like fro IVO to IVC and how does it change with an increase in RPM?
Stan
I could quite easily go one or 2 steps further when I say I use turbos?
1 bar boost?
2 bar boost
Or more?
How much pressure differential is that?
If you've made the effort to measure all 4 events of the cam on cylinder 1, repeat with the opposite cylinder.
Are the events the same?
Should they be?
What about all the other cylinders?
They'll always measure a bit different.
Joe,
Let talk about the top end. 60 psi / 1660 inch of water. If you were able to flow a head at this depression you would see air speed somewhere around mach 2.
So why on a running engine will we see less than mach 1 for air speed in the intake port?
Because the pressure differential is nowhere near where you think it is.
GARY C wrote: ↑Thu May 17, 2018 10:29 pm
Some see the events as a byproduct but we have been through this. Does it really matter at the end of the day if you end up with the same cam?
Would the others be wrong for saying your method is incorrect because you don't start with LSA and Overlap?
Oddly enough the second group would not say you are wrong they would be interested in learning how you do it.
It matters because tuning the events requires understanding of the gas dynamics of the engine.
It is similar to the difference between a cook and a trained chef;
A cook knows how to follow recipes and maybe tweak it some based on experience to get a different result, but they don't really know why it works.
A trained chef, understands the chemistry of food and knows the reasons for proportions, what will happen and why when changes are made.
Too many adjustments for my brain to deal with, it would probably get me in trouble.
If memory serves me right the one I saw ran a 106 through the meat of the pull moving to a 109 and ending with a 113... It might have been Jon that posted it years ago.
Couldn't be, he knows nothing! Lol
In all seriousness, the events are what you need to focus on to take it to the next level. Everything else is just a byproduct.
Some see the events as a byproduct but we have been through this. Does it really matter at the end of the day if you end up with the same cam?
Would the others be wrong for saying your method is incorrect because you don't start with LSA and Overlap?
Oddly enough the second group would not say you are wrong they would be interested in learning how you do it.
Gary,
If that is not the most asked and unanswered question on ST in the last 6 months I would like to know what is?
Couldn't be, he knows nothing! Lol
In all seriousness, the events are what you need to focus on to take it to the next level. Everything else is just a byproduct.
Some see the events as a byproduct but we have been through this. Does it really matter at the end of the day if you end up with the same cam?
Would the others be wrong for saying your method is incorrect because you don't start with LSA and Overlap?
Oddly enough the second group would not say you are wrong they would be interested in learning how you do it.
Gary,
If that is not the most asked and unanswered question on ST in the last 6 months I would like to know what is?
Stan
What has not been answered?
How to develop cam specs?
Couldn't be, he knows nothing! Lol
In all seriousness, the events are what you need to focus on to take it to the next level. Everything else is just a byproduct.
Some see the events as a byproduct but we have been through this. Does it really matter at the end of the day if you end up with the same cam?
Would the others be wrong for saying your method is incorrect because you don't start with LSA and Overlap?
Oddly enough the second group would not say you are wrong they would be interested in learning how you do it.
Gary,
If that is not the most asked and unanswered question on ST in the last 6 months I would like to know what is?
Stan
True, I think Cam King is the only one that ever explained the frame work of his method but I don't recall anyone else willing to show what they claim.
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
GARY C wrote: ↑Thu May 17, 2018 10:29 pm
Some see the events as a byproduct but we have been through this. Does it really matter at the end of the day if you end up with the same cam?
Would the others be wrong for saying your method is incorrect because you don't start with LSA and Overlap?
Oddly enough the second group would not say you are wrong they would be interested in learning how you do it.
It matters because tuning the events requires understanding of the gas dynamics of the engine.
It is similar to the difference between a cook and a trained chef;
A cook knows how to follow recipes and maybe tweak it some based on experience to get a different result, but they don't really know why it works.
A trained chef, understands the chemistry of food and knows the reasons for proportions, what will happen and why when changes are made.
Thats why I cook all my own food, if I wanted to taste seasoning I would just eat seasoning!
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
GARY C wrote: ↑Thu May 17, 2018 11:48 pm
True, I think Cam King is the only one that ever explained the frame work of his method but I don't recall anyone else willing to show what they claim.
It has been explained many times, I can only conclude that you are not willing or able to learn unless it fits what you want to believe.
GARY C wrote: ↑Thu May 17, 2018 11:48 pm
True, I think Cam King is the only one that ever explained the frame work of his method but I don't recall anyone else willing to show what they claim.
It has been explained many times, I can only conclude that you are not willing or able to learn unless it fits what you want to believe.
Jon,
Must have been in threads that I have not read. Can you please post links to posts that tell me how to calculate IVC ro EVO.
Stan Weiss wrote: ↑Thu May 17, 2018 10:53 pmJoe,
Let talk about the top end. 60 psi / 1660 inch of water. If you were able to flow a head at this depression you would see air speed somewhere around mach 2.
Stan
I don't think air speed in a port can exceed Mach 1. The extra mass flow on supercharged engines is mostly due to increased density - not increased speed.
GARY C wrote: ↑Thu May 17, 2018 11:48 pm
True, I think Cam King is the only one that ever explained the frame work of his method but I don't recall anyone else willing to show what they claim.
It has been explained many times, I can only conclude that you are not willing or able to learn unless it fits what you want to believe.
Jon,
Must have been in threads that I have not read. Can you please post links to posts that tell me how to calculate IVC ro EVO.
So your not confident enough in your cam selection to choose 1, fine tune it on the dyno and put it into competition?
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
There is definitely not one set of centerlines that are ideal through a broad rpm range.
