Is TPS required in EFI?
Is TPS required in EFI?
(OP)
Hey Guys,
i was just wondering about the basic Electronic Fuel Injection System for a Samll Single cylinder engine? If I use the MAP sensor for the load sensing and Crankshaft Signal for Speed sensing (Basically Speed density method), can i get away with TPS (& use a normal mech throttle body)? I came to know that TPS is only used for Acceleration Enrichment is those cases? Can't i sense the Acceleration with the changes in the MAP signal & inject the fuel accordingly? Can i do it without scarificing the engine response factor?
I know that there are too many questions, but those all are my thots running in my mind, May be you guys would have in-depth knowledge or work experience, which would answer my queries.
Thanks
Santo RTA
i was just wondering about the basic Electronic Fuel Injection System for a Samll Single cylinder engine? If I use the MAP sensor for the load sensing and Crankshaft Signal for Speed sensing (Basically Speed density method), can i get away with TPS (& use a normal mech throttle body)? I came to know that TPS is only used for Acceleration Enrichment is those cases? Can't i sense the Acceleration with the changes in the MAP signal & inject the fuel accordingly? Can i do it without scarificing the engine response factor?
I know that there are too many questions, but those all are my thots running in my mind, May be you guys would have in-depth knowledge or work experience, which would answer my queries.
Thanks
Santo RTA





RE: Is TPS required in EFI?
If it were carbureted, would the engine/application need an accelerator pump?
RE: Is TPS required in EFI?
-Tony Staples
www.tscombustion.com
RE: Is TPS required in EFI?
Thankx for sharing for ur experience.
What happens if the air filter is clogged? How will the Speed-density system work, if the MAP is going to show erroneous value?
Santo RTA
RE: Is TPS required in EFI?
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RE: Is TPS required in EFI?
patprimmer is right, of course! But, the engine has to be able to handle variations in air filtration efficiency because that is the "real world." If the air filter is heavily clogged, it will reduce the amount of air ingested at a given throttle opening and rpm. The MAP sensor will read this as a lower absolute manifold pressure, and reduce the fueling accordingly, assuming the engine is calibrated properly.
There are many speed density systems used on small engines. For example, Harley Davidson used an EFI system with a TPS up to 2001. When it switched over to the newer Delphi injection system in 2002, it switched to a speed density system with a MAP sensor. There are pros and cons to both types of systems.
-Tony Staples
www.tscombustion.com
RE: Is TPS required in EFI?
But how quick the response of MAP system will be for a two wheeler engine (some quantification?) As you said before, it wont be as crisp as TPS system, but whether the MAP system will be atleast upto the mark, if not the best?
Santo RTA
RE: Is TPS required in EFI?
I've been out of the loop in engine control systems for 3-4 years now. The technology continues to move forward. For a typical motorcycle application, I would investigate what you can find that has already been optimized for that type of application. I would think that ECU package size (Not a lot of available package space with adequate cooling, on a motorcycle) would be a bigger concern than the minor difference in throttle response (only maybe) that might be experienced between two systems. Talk to some companies that do custom hardware, and find out who is specializing in motorcycles.
-Tony Staples
www.tscombustion.com
RE: Is TPS required in EFI?
RE: Is TPS required in EFI?
RE: Is TPS required in EFI?
RE: Is TPS required in EFI?
RE: Is TPS required in EFI?