I've been looking at the posts for a while & finally joined. What a great site. I'm going to start on a few mods this weekend, planning on doing a little grill blocking and making a pcv catch can. I did also have a question about a kill switch on my 95 civic. Is this a good ideal or should I just turn the key off. Concerned about locking the steering on the highway. If you have any suggestions, please let me know.
Besides locking the steering wheel I'd be concerned with losing power brakes and power steering (if your car has power steering). Also you lose the ability to hit the throttle to avoid an accident. It's also illegal.
When you let off the throttle above 1000 RPM your fuel injectors are turned off in an ECU strategy called "deceleration fuel cut-off".
suspendedhatch, lots of people seem to be deathly afraid that they won't be able to accelerate away from a possible accident. I'm sure such situations exist. However, in nearly half a million miles of driving, I can't say for sure that I've ever been in such a situation, except during times that I would never consider EOC. The only specific time I can remember accelerating away from danger is during difficult blind left turns where I have to jump out in traffic -- certainly not a time when it's even physically possible to EOC.
DFCO is great if you intend to slow down, but if you intend to keep going, idling in neutral is better. The gas you spend idling isn't as much as the energy you lose from engine braking, which you will later have to spend in gas to gain back the speed you lost. I believe this is mainly because of the extra energy required to pump air and create heat from friction when you turn the engine more revolutions than you would idling in neutral.
Dogbite, is your car equipped with a manual or automatic transmission? If it's automatic you probably should not EOC at all.