EGT sensors and knock sensors

[erny]

Do most teams use EGT sensors and knock sensors. If so which ones.

With f4 is knock a problem? If so where on map? I have seen mixed views on forum.

[Erich Ohlde]

EGT's are a good idea on the dyno, but once you get your map figured out, its not really necessary on the car. Knock isn't a problem with a lot of the 600 fsae motors. we had an f3 running 70 degrees of timing all through competition and summer, that motor never blew.

[Benjlv]

just curious why were you running so much timming? and was it at peak torque and so on? also are you sure that was the actual timming...

[Erich Ohlde]

it was an accident on our 99 car. we were using some v8 engine controller and it doubled the timing i guess. I wasn't around. I've just heard the stories

[Bowtie Man]

EGT sensors are a really good idea, I'm using a new set from Team Rip Engineering they can be found at www.teamrip.com (http://www.teamrip.com)

Luc

[EfiOz]

What are you using them for?

[Erich Ohlde]

EGT's can be used to fine tune the cylinder to cylinder fuel enrichment (assuming you are using sequential EFI). Some people think it should be used to fine tune timing but I don't really subscribe to that theory

[Dan Deussen @ Weber Motor]

Fine tuning individual cylinder fueling based on EGT's will not assure that the cylinders run at the same air/fuel ratio. Air distribution variances are created by intake manfolds resonances. It is much more important to match the air/fuel ratio of all cylinders and this can only be achieved with wideband oxygen sensors. If you just adjust the fueling of individual cylinders to match EGT's, I guarantee that you will have cylinders that run too rich and ones that run too lean. EGT's are a good indicator of misfires when sampled fast enough. They are also good for making sure you don't melt pistons, valves and/or other parts of your motor hardware.

EGT measurements can also variy because of differences in mountig depth, distance from valves, how cooling air is flowing over the headers and nonetheless tolerances of the sensors themselves.

[EfiOz]

that's fine when you have a static timing setup as in a go kart but how do you figure out what's a lean mixture and what's simply retarded timing?

[Dan Deussen @ Weber Motor]

EfiOZ,

What exactly are you referring to?

[EfiOz]

That yuo can fool yourself into thinking you have a lean mixture when really you have late timing. For that reason alone an EGT is a fairly awful judge of air/fuel mixture.

I do admit that once mapped correctly, a single EGT plugged into the data logging system is a quick way to see a dead cylinder. But they are not a very good tuning tool, especially for the beginner.

[Erich Ohlde]

I disagree, EGT's are a very powerful tool when setting up the fuel/ignition map, especially if you are running a turbo. If you set up your timing correctly for max power EGT's can help cylinder to cylinder trims. Although, like Dan said multiple O2 sensors are a far more accurate tool. Think EGT-Tape measure to O2 sensor-micrometer