Do these pictures need captions? (32V Intake Manifold Study - HP)
#61
You DO make power, depending on other factors, if you leave the intake valve open longer. If you can get the air moving with enough momentum (air has mass, therefore momentum) you can get it to "push" itself into the chamber.
#62
Drifting
yes , I didnt think you wanted any....sure I am going to get it retuned alittle and send the last dyno , or all of them, what ever you would like,,,,seeing the diff from the initial to final tune really made a huge difference...I will search.(file system good for medicine but not for car stuff)
#63
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yes , I didnt think you wanted any....sure I am going to get it retuned alittle and send the last dyno , or all of them, what ever you would like,,,,seeing the diff from the initial to final tune really made a huge difference...I will search.(file system good for medicine but not for car stuff)
That entire "Link" fuel injection system and the interaction with Neil Harvey was not a very good experience....I'd love to see what the changes accomplished.
__________________
greg brown
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Semi-retired, as of Feb 1, 2023.
The days of free technical advice are over.
Free consultations will no longer be available.
Will still be in the shop, isolated and exclusively working on project cars, developmental work and products, engines and transmissions.
Have fun with your 928's people!
greg brown
714 879 9072
GregBBRD@aol.com
Semi-retired, as of Feb 1, 2023.
The days of free technical advice are over.
Free consultations will no longer be available.
Will still be in the shop, isolated and exclusively working on project cars, developmental work and products, engines and transmissions.
Have fun with your 928's people!
#64
#65
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If my understanding is correct, that wikipedia "explanation" has a number of errors. Someone should edit it.
For an engine operating with the optimal intake valve closing point, the air at the valve is not moving in either direction when the valve closes. If it were still moving towards the cylinder, you'd make more power by keeping the valve open a bit longer -- air is still going into the cylinder!
Not all manifolds, or even most manifolds, use the Helmholtz effect. Unless you get really technical and call the cylinder the Helmholtz resonator, but that's not what they mean.
The pressure wave reflected from the cylinder near the piston BDC is a pressure wave and it's reflected from the runner mouth as a rarefaction wave in most manifolds. Increases in the cross-sectional area reflect a wave of opposite sign, while decreases in the cross-sectional area reflect a wave of the same sign.
The waves don't move at the speed of sound relative to the runner, they move at the speed that combines the speed of the air in the runner and the speed of the wave in the air. The wave theory that is predictive in engines is the finite wave theory, while the harmonic wave theory really isn't.
I am not pretending to be the authority on the topic, all I am saying that I can't personally make sense of much of what I read from that Wikipedia article. That says something about me and/or the Wikipedia article but what exactly it says is everyone's own judgement.
For an engine operating with the optimal intake valve closing point, the air at the valve is not moving in either direction when the valve closes. If it were still moving towards the cylinder, you'd make more power by keeping the valve open a bit longer -- air is still going into the cylinder!
Not all manifolds, or even most manifolds, use the Helmholtz effect. Unless you get really technical and call the cylinder the Helmholtz resonator, but that's not what they mean.
The pressure wave reflected from the cylinder near the piston BDC is a pressure wave and it's reflected from the runner mouth as a rarefaction wave in most manifolds. Increases in the cross-sectional area reflect a wave of opposite sign, while decreases in the cross-sectional area reflect a wave of the same sign.
The waves don't move at the speed of sound relative to the runner, they move at the speed that combines the speed of the air in the runner and the speed of the wave in the air. The wave theory that is predictive in engines is the finite wave theory, while the harmonic wave theory really isn't.
I am not pretending to be the authority on the topic, all I am saying that I can't personally make sense of much of what I read from that Wikipedia article. That says something about me and/or the Wikipedia article but what exactly it says is everyone's own judgement.
To answer Leon's simple question, I think how that happens is somewhat moot...
#66
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Someone who apparently had never used "Link" before and made the car run much better, the very first day he worked on it.
He must be a God.
Neil Harvey wanted another 10K to "refine" the tuning that was done on the dyno, once the engine was in the car. I did the best I could do....which left plenty of "room" for improvement (I completely "ran out of talent".)
I'm very happy to be using the Alpha N injection pieces (original Bosch without MAF), from John Speake and Sharkplotter, by Jim Corenman, on this project. At the very least, I know that when I run out of talent, Rob Edwards and Jim Corenman can tune the thing.....and if I need any technical help, John Speake will answer my questions the same day!
This group of guys are the very best....and make stuff like this fun!
He must be a God.
Neil Harvey wanted another 10K to "refine" the tuning that was done on the dyno, once the engine was in the car. I did the best I could do....which left plenty of "room" for improvement (I completely "ran out of talent".)
I'm very happy to be using the Alpha N injection pieces (original Bosch without MAF), from John Speake and Sharkplotter, by Jim Corenman, on this project. At the very least, I know that when I run out of talent, Rob Edwards and Jim Corenman can tune the thing.....and if I need any technical help, John Speake will answer my questions the same day!
This group of guys are the very best....and make stuff like this fun!
#67
Nordschleife Master
Yes, we can agree about that.
#68
I really wish you guys had gone to see the "other" Neel. Neel of Apex. He is very good, and its well known that he is.
For a street driven car its Dyno, Street, Dyno, Street sometimes. Add in cold starts, and its "5am in the morning on a cold day before you go to work"
For a street driven car its Dyno, Street, Dyno, Street sometimes. Add in cold starts, and its "5am in the morning on a cold day before you go to work"
Someone who apparently had never used "Link" before and made the car run much better, the very first day he worked on it.
He must be a God.
Neil Harvey wanted another 10K to "refine" the tuning that was done on the dyno, once the engine was in the car. I did the best I could do....which left plenty of "room" for improvement (I completely "ran out of talent".)
I'm very happy to be using the Alpha N injection pieces (original Bosch without MAF), from John Speake and Sharkplotter, by Jim Corenman, on this project. At the very least, I know that when I run out of talent, Rob Edwards and Jim Corenman can tune the thing.....and if I need any technical help, John Speake will answer my questions the same day!
This group of guys are the very best....and make stuff like this fun!
He must be a God.
Neil Harvey wanted another 10K to "refine" the tuning that was done on the dyno, once the engine was in the car. I did the best I could do....which left plenty of "room" for improvement (I completely "ran out of talent".)
I'm very happy to be using the Alpha N injection pieces (original Bosch without MAF), from John Speake and Sharkplotter, by Jim Corenman, on this project. At the very least, I know that when I run out of talent, Rob Edwards and Jim Corenman can tune the thing.....and if I need any technical help, John Speake will answer my questions the same day!
This group of guys are the very best....and make stuff like this fun!
#69
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Subscribed. There goes another reason to not buy a plane and stick the money into my 928
#70
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You'd think that the guy that imports the stuff, talks to the people that make it on a daily basis, and claims to be a great tuner could take care of it...or at least I did.
#71
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And different things happen at different RPM's, because the runners don't change lengths. So all theories are correct, and incorrect, depending.
Greg, that looks awesome!
#73
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#74
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Which all has to do with velocity (MV^2), which in turn depends on runner and port diameters... Bigger isn't always better, less resistance but also less velocity.
And different things happen at different RPM's, because the runners don't change lengths. So all theories are correct, and incorrect, depending.
Greg, that looks awesome!
And different things happen at different RPM's, because the runners don't change lengths. So all theories are correct, and incorrect, depending.
Greg, that looks awesome!
#75
Official Bay Area Patriot
Fuse 24 Assassin
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Thanks Greg. I am on a Droid. Must have missed it...
I am curious to know how the throttle linkage assembly on the left side of the factory manifold will be adapted to this new intake.
I am curious to know how the throttle linkage assembly on the left side of the factory manifold will be adapted to this new intake.