Fuel for Gassers

RLS7201 wrote:
Why does premium fuel give more mileage and power?

Richard

Richard,

This is a very good question, and I will try to answer it without getting too "engineer" for you.

In times past, engines did not have a computer to control fuel mixture and ignition timing. Now many do.

They listen intently for any knock that is the result of wrong conditions including spark timing. When they hear a knock, the box will start a bunch of corrections that some engineer has tested and advised. Usually the cure is to back off the spark timing. While this will cost some mileage, because the ECU (Engine Control Unit)never gets tired of listening and gets board at sitting still, when it hasn't hear a knock in a while, it will dial in more timing advance. It may also lean out the mixture a little (he can also use fuel to quell a knock). Another correction that many ECU have is to lower the engine temperature. There is not a great deal he can do here, but it is again involved with fuel mixture and sometimes the engine fan speed control.

When you have your very own computer and a raft of sensors, you can pull off all manner of nifty things.

If I lost anybody in here, come back and I will try again.

Matt