New injection installed Looks just like the Webers!

[Aussie Mike]

Originally Posted by dlampe

Thanks for the clarification on the open loop terminology. What determines how much HP a system can handle? Is it the injector size? Fuel pressure? Throttle body diameter?

Injectors are matched to specific fuel pressure. It can be varied but they have a specific pressure range they work at their best. Injectors need to be sized to support the amout of power the rest of your motor will make they will flow X ammount of fuel at a particular duty cycle. If the ECU is having to hold the injectors open 100% at full power then you probably need bigger injectors.

FI systems seem to be able to handle a lot more airflow than an equivalent carb setup. I'm running a 1000CFM throttle body and it runs great but a 1000CFM carb would be a pig. FI will probably make similar top end power to a properly setup carb motor. Where the gain is is in drivability and low end mid range power. With the injector placed right at the port in the head the fuel doesn't have a chance to fall out of suspension at low gas velocities i.e when you open the buttterflies on a big carb at low RPM. The carb uses a big shot of juice from the accelerator pump squirters to fix a mixture that's suddenly become lean because all the fuel is now sitting in the bottom of the manifold.

Cheers