So far what I have for my exhaust O2 safty is at the bottom of the page here

 

To advanced?

 

not sure what you're asking... but by the time that thing cuts out the 'noids you'll have blown somethign up.

O2's are very slow to respond and do not respond in a useful range.

 

That's what I wanted some feed back.
How slow are they?
The amp and the darlington switch are real fast, like 10uS delay at most.

 

You can literally watch them change value, so they’re pretty slow, which is why you really can’t tune WOT using them. By the time you see the change you’ll already need to carry the engine home in a bucket.

If you want to try something useful tap into the KS circuit (probably after the buffer/filter) and have it shut off after a set number of knocks…

 

thats similar to what alot of nitrous computers do.

since the nitrous jetting makes it super rich, it reads low enough on the O2 to measure a threshold.... basicly as long as you're rich, keep the juice on.


ideally id use a microcontroller to time it and such, but that should work fine as a saftey device.... the O2s should be reading rich at WOT before the nitrous kicks on anyway.


as far as O2 sensor responce time, its pretty damn fast...........when you have a fast connection to it..... when using a microcontroller doing things in µs, you can still see a measurable change every 3µs or so... they dont seem to be that slow.








then again, reading them on a slow gauge, or after they've been read by a ECM, turned to serial data, then streamed to the PC, they'll seem really slow.

 

That is kind of why I picked a heated o2.
The voltage values change with temp so there isn't .xxx volts = x to 1 A/f allways, I could set the voltage higher like .850 or .900 so that it would cut off if it went below 14 or 13 to 1.
The heated o2 will make the o2 sensor filiment temp more stable.
Timing gears like I want to use don't work with knock sencors.

"ideally id use a microcontroller to time it and such, but that should work fine as a saftey device.... the O2s should be reading rich at WOT before the nitrous kicks on anyway."
That is what I was thinking.

as far as O2 sensor responce time, its pretty damn fast...........when you have a fast connection to it..... when using a microcontroller doing things in µs, you can still see a measurable change every 3µs
Darlington transistors are decribed as a low speed switching decices, I could toss the darlington switch for a Field Effect Transistor. They are responsive down to the fractoin of a uS.