Duty Cycle
#4
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I presume you want the DC to be higher to have a better Idle? unfortunately you SOL mate.
#5
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my car keeps shaking like crap at idle...i can't even drive it after i put in the mspnp i read the manual but crap...i can't get this thing going so i'm just asking some radom questions LOL....i am running 550cc high impedance injectors and 255 walbro fuel pump...i'm getting like a 18.? at air fuel ratio.... i think thats suppose to be really lean... what can i do to make my car at least driveable to the dyno so i dont get ripp the heck off...
#7
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alright...i'll try messing with the VE table...and yeah....i did do the require fuel....i think it was in the engine constant where i have to enter my engine displacement...and injectors size...
#12
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The MSPNP has opened the doors of incompetency, atleast before when people had to do something besides hook up a few connectors they understood that reading and comprehension was an important part of standalone engine management. If they didn't understand that they couldn't complete the project.
RTFM FTW
RTFM FTW
#17
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The MSPNP has opened the doors of incompetency, atleast before when people had to do something besides hook up a few connectors they understood that reading and comprehension was an important part of standalone engine management. If they didn't understand that they couldn't complete the project.
RTFM FTW
RTFM FTW
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#18
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The Megasquirt is based on pulse width, not duty cycle. Increasing the pulse width, of course, increases duty cycle. Some basics on how it works:
1. The Req_Fuel number is best described as your base pulse width. Adjust it to move your entire pulse width up or down.
2. The Megasquirt then calculates the air density from the MAP and IAT sensor readings.
3. Then it multiplies the pulse width from step 2 by the percent in the VE table.
4. It applies anything from correction tables, like acceleration enrichment.
5. Finally, it adds on the injector opening time to the pulse width.
It sounds like what you need is a higher VE setting at idle.
1. The Req_Fuel number is best described as your base pulse width. Adjust it to move your entire pulse width up or down.
2. The Megasquirt then calculates the air density from the MAP and IAT sensor readings.
3. Then it multiplies the pulse width from step 2 by the percent in the VE table.
4. It applies anything from correction tables, like acceleration enrichment.
5. Finally, it adds on the injector opening time to the pulse width.
It sounds like what you need is a higher VE setting at idle.
#19
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You can do this stuff, but you have to read the manual. Sit down one day, away from the car, and read the manual cover to cover. You might have to read it again, later, to apply some of the concepts and rationalize others. You might want to buy a book on tuning FI. I believe Matt Cramer told me the title of a good one on the phone, which I don't remember, but now wish I had so I wouldn't look like an irresponsible *******, calling the kettle black when I'm a dark shade of gray.
I expect to have a ton of stupid problems that will get me banned from this forum, but I will be certain to read the manuals (again) first.
I expect to have a ton of stupid problems that will get me banned from this forum, but I will be certain to read the manuals (again) first.