New 572 builds hp guesses
#71
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
This efi stuff is cool chit, i cannot see how you can do all that it can do, by not getting a setup on an engine dyno. How can you do all this stuff by tuning on the water on a custom build? So much that can be tuned. Timing maps, fuel maps, injector timing, knock sensor setup, and so on.
#72
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Joined: Mar 2004
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From: Pa
It be interesting to see what happens to the bsfc , with changing injector timing. I assume the camshaft events can dictate a need for a change in injector timing? Id think that if the injector timing was based on say a stock cam, and you go to a bigger cam, that opens the exhaust valve sooner, and had more overlap, maybe firing the injector later, so that you arent blowing fuel out the exhaust?
Maybe not much power to be gained here, but maybe some fuel efficiency? Just thinking out my azz on this
Maybe not much power to be gained here, but maybe some fuel efficiency? Just thinking out my azz on this
#73
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Joined: Mar 2004
Posts: 2,696
Likes: 93
From: Pa
This efi stuff is cool chit, i cannot see how you can do all that it can do, by not getting a setup on an engine dyno. How can you do all this stuff by tuning on the water on a custom build? So much that can be tuned. Timing maps, fuel maps, injector timing, knock sensor setup, and so on.
Last edited by GPM; 04-01-2017 at 09:51 AM.
#74
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Joined: Jan 2006
Posts: 3,860
Likes: 793
From: St. Pete Beach, FL
It be interesting to see what happens to the bsfc , with changing injector timing. I assume the camshaft events can dictate a need for a change in injector timing? Id think that if the injector timing was based on say a stock cam, and you go to a bigger cam, that opens the exhaust valve sooner, and had more overlap, maybe firing the injector later, so that you arent blowing fuel out the exhaust?
Maybe not much power to be gained here, but maybe some fuel efficiency? Just thinking out my azz on this
Maybe not much power to be gained here, but maybe some fuel efficiency? Just thinking out my azz on this
#75
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
It takes a while, it's not as easy as some of the salesmen on here claim. Some of the systems are less complicated than others, the parameters have to be set for the marine application. They can be amazing once dialed in, some may throw it in the lake before getting there. Try putting dual wideband 02s on your carb motors, they may not be working as well as you thought.
#76
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Joined: Mar 2004
Posts: 2,696
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From: Pa
I've been wondering if injection timing could be used to help push more air in the cylinder. Use something kind of like a miller cycle cam with late ivc and inject when the piston is at or near bdc and the airflow has pretty much stopped. You would need large capacity injectors which could handle most of your fueling needs in a short window of time.
#78
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
Currently, I have a single ngk powererdex wideband. I did have dual FAST unit prior to the NGK. On the dynos, I have used the NGK, and Daytona sensors widebands.
My engines bank to bank wise, have never varied more than a couple tenths. I believe that is thanks to the dual carb setups, and straight two lobe rotors. My buddy's with twisted lobes, shows a little bit more difference from bank to bank, but nothing crazy.
My engines bank to bank wise, have never varied more than a couple tenths. I believe that is thanks to the dual carb setups, and straight two lobe rotors. My buddy's with twisted lobes, shows a little bit more difference from bank to bank, but nothing crazy.
#79
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Joined: Jan 2006
Posts: 3,860
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From: St. Pete Beach, FL
It can theoretically greatly improve economy by having localized stoich mixture only around the spark plug. But I think emissions prevent fully utilizing that strategy.
#80
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Joined: Mar 2004
Posts: 2,696
Likes: 93
From: Pa
Currently, I have a single ngk powererdex wideband. I did have dual FAST unit prior to the NGK. On the dynos, I have used the NGK, and Daytona sensors widebands.
My engines bank to bank wise, have never varied more than a couple tenths. I believe that is thanks to the dual carb setups, and straight two lobe rotors. My buddy's with twisted lobes, shows a little bit more difference from bank to bank, but nothing crazy.
My engines bank to bank wise, have never varied more than a couple tenths. I believe that is thanks to the dual carb setups, and straight two lobe rotors. My buddy's with twisted lobes, shows a little bit more difference from bank to bank, but nothing crazy.


