| Author | Message | ||
     Thumper74 |
I'm interested in fabbing a turbo kit for my Buell. I haven't been paying attention when I've replaced parts on the Buell, but is there a fuel pressure regulator? Is it speed density? | ||
| Tdman77 |
The X1 has a fuel pressure regulator. As for the type of system, I think it's a Mass Air type since it has a IAT (intake air temp) sensor similar to my 91 mustang and not a barometric sensor. | ||
| Firebolt1203 |
Pretty sure its speed density. Mass air requires a flow meter that shows how much air is entering the engine at any given point. The meter also corrects for changes in density. There is also an Inlet Air temperature sensor, Manifold Air Pressure sensor, and some other I cant remember. Mass airs big benefit is being able to adjust to almost anything, it wont run perfect but it can make adjustments to be quasi drivable. I've always heard a speed density type system make a little bit more HP, and as long as you have it mapped right you shouldn't have a problem. Problem is creating a fuel map to match the boost curve and all that junk. | ||
| Tdman77 |
On my 91 Mustang it was just the opposite of what you described. The Mas air sensor (very similar to our IAT) measured the intake of air (O2)into the motor and the O2 sensor measured the out put. The computer would try to maintain the 14.7/1 air ratio programed into it. Pre 90 Mustangs had a speed density system which used a MAP sensor and no intake sensor. This was a very poor system that could not adapt to all but the smallest changes. The AFV built into the stock ECM of our Buells does a pretty good job with intake/exhaust mods. Only when major mods are done does the fuel and timing maps need to be changed. With larger injectors and an experienced dyno tech a turbo system should be able to work with the DDFI system. | ||
| Buelltuner |
actually fellas, the Buell system is neither speed density nor mass air flow. The function of the IAT is to determine temp not density, it does have some ability to change fuel delivery but it is a small percentage. The system is an Alpha/N system. It relies on input from the TPS to calculate relative engine load. This is why sometimes resetting the TPS can be a very good thing. It is the most basic of fuel injection systems. Harley's 2002 and later that use Delphi systems are speed density systems that use a MAP sensor to measure vacuum in the throttle body. Those are the two kinds of EFI systems that Harley has ever used. | ||
| Mesozoic |
Buelltuner, do you have anything to say about tuning '08 and newer Buells? I've heard there is a method of using ECMSpy to tune, but not sure where to find more specific info. |
