Which is faster carb or Fuel injection?

Signman · 07-24-2013, 09:11 AM

Besides blueprint specs take a look at the intake potential and carb size vs. the throttle body, plenum and runners. There may be some differences. If you could estimate actual air flow available at the port would be big.
Fuel injection could have an advantage in having fuel introduced close to the back of the valve vs. being carried in suspension with the air stream.

With injection being able to control AF Ratio through the operating RPM range should be an advantage. Most systems will allow you to define RPM range in each cell but the amount of cells in the table is limited. Most are 400 or 500 RPM per cell. Think about the RPM range an engine operates in high gear. In low gear the time spent in each cell is minimal and controlling fuel is difficult.
Theoretically sequential vs. batch fire should have an advantage along with individual cylinder timing, etc. The real word variable is the operating RPM range, time spent in each cell, speed of the processor and speed of the injector.
Theoretically speed density / closed loop should be optimal vs. open loop or Alpha-N when the air fuel table is optimal. But it may not.

What I've come to understand is a carb will make more peak HP while EFI will make a flatter curve. Would average HP be similar?

07-24-2013, 09:11 AM	#9
Signman Senior Member Join Date: Oct 2003 Location: Lower Slower Delaware Posts: 535 Likes: 22 Liked 269 Times in 99 Posts	Re: Which is faster carb or Fuel injection? Besides blueprint specs take a look at the intake potential and carb size vs. the throttle body, plenum and runners. There may be some differences. If you could estimate actual air flow available at the port would be big. Fuel injection could have an advantage in having fuel introduced close to the back of the valve vs. being carried in suspension with the air stream. With injection being able to control AF Ratio through the operating RPM range should be an advantage. Most systems will allow you to define RPM range in each cell but the amount of cells in the table is limited. Most are 400 or 500 RPM per cell. Think about the RPM range an engine operates in high gear. In low gear the time spent in each cell is minimal and controlling fuel is difficult. Theoretically sequential vs. batch fire should have an advantage along with individual cylinder timing, etc. The real word variable is the operating RPM range, time spent in each cell, speed of the processor and speed of the injector. Theoretically speed density / closed loop should be optimal vs. open loop or Alpha-N when the air fuel table is optimal. But it may not. What I've come to understand is a carb will make more peak HP while EFI will make a flatter curve. Would average HP be similar? __________________ Frank Ferrucci I/SA 1271 "Be Thankful for the Gifts You are Given"