injection engine

[Reactive]

Hi all,

I wonder what modifications we should make on a fuel injected engine, due to the intake restrictor.

In case we use an engine with fuel injection, yzf r6 or cbr 600 to be more specific, do we have to reprogram ECU to decrease injected fuel? Or does the engine regulates fuel amount automatically?

We are a first year team and I would appreciate any tips on whether to use a carburator or an injection system.

Thanks...

Hakki Can Koman
ITU Formula SAE Team
Engine and DriveTrain Development

[Reactive]

Hi all,

I wonder what modifications we should make on a fuel injected engine, due to the intake restrictor.

In case we use an engine with fuel injection, yzf r6 or cbr 600 to be more specific, do we have to reprogram ECU to decrease injected fuel? Or does the engine regulates fuel amount automatically?

We are a first year team and I would appreciate any tips on whether to use a carburator or an injection system.

Thanks...

Hakki Can Koman
ITU Formula SAE Team
Engine and DriveTrain Development

[absolutepressure]

Don't carburate it. To comply with the rules, the carburator would have to be upstream of the restrictor, which would give your whole intake a nice gasoline bath which would just be asking for a backfire up the intake valve to blow it all to hell.

Your computer should (I've never delt with bike computers before) determine the proper amount of fuel to provide to the engine given any amount of air in the intake. The only problem is that the fuel being delivered may be so low that the injector's duty cycle (how much they spray out) would be reduced into it's inefficiency level. If you go with smaller injectors, they can squirt smaller amounts of fuel in a more efficient way. For an extreme example, it's like the difference of trying to inject a drop of gas with a garden hose as opposed to a spray bottle.

[Preston Schipper]

Your ECU should use a speed density calculation for the fuel. It senses the pressure in the manifold for this calculation. As you hit points where the restrictor effects you, the manifold will start to see more vacuum and thus, less fuel will go in. So you should be ok on that account for the most part. I would be more concerned with the manifolds you use as they will change resonances, etc where your fueling might change. For a first year team check out the power commander. They are a great way to get you going before you make a step up to standalone engine mangement.