Finally someone found and actually read through this LOL.

Anyway.. the engine is/was a donation from Ford. They have a strong relationship with UW-Madison where I went to college (graduated yesterday). The engine is from a Ford Contour.

The only thing in the lab that my group and I didn't write ourselves was the equipment list... And I never looked at it until just now. That is a typo about the manifolds. It had two seperate manifold areas for the cyldiners (because of it being a V6) So it had two manifolds, one for each cylinder bank. At least that is what I think I remember seeing. But it does for sure have 4 valves per cylinder, two intake and two exhaust.

Just glad to provide information we can all learn from!

 

why wasn't there any testing of oxides of nitrous and the effect of the egr valve? there wasn't one? just asking since you did have a exhaust gas analyzer but no data on NoX. i figured it would play a role in exhaust temps if the engine did have it equiped than if it had not.

 

also, is your use of retard and advance backwards? you said that retarding timing increases exhaust temps, but i always thought opposite. (plot 4)

 

Unfortunately the exhaust gas analyzer we had did not do nitrous oxides. So yeah that is one thing that is definitely missing from the report.

I just double checked the actual data itself and is indeed true that we found lower exhaust temps with advanced timing.

We had originally misunderstood timing and had it reversed. So we were confused when we found retarding the timing giving us more horsepower . But we got it straight in the end. The bigger the angle the earlier it is, as timing is measured BEFORE top dead center (TDC).

The most likely reason for the cooler exhaust temps is that the burn has completed sooner because of the earlier ignition and you are actually getting less "still burning" or "just burned" mixture exiting at that time. Therefore giving you the much cooler temperatures.

PLOT 4 is actually A/F and rpm's being changed, not any timing differences.

 

what you are probably thinking of is that advancing your timing results in a much higher TDC temperature. This is due to the fact that you heat the mixture by compressing it, and if it is already burning you are further heating it. Then you can actually reach temperatures that will cause all of the air fuel mixture to spontaneously ignite and that generates an explosion which we call detonation or "knock." Typically, the mixture burns evenly and has a "flame front" that burns through the mixture at a controlled rate. Advancing your timing allows you to make it possible for that flame front to burn through the entire power stroke instead of say the last 2/3's of the stroke as could/would happen when timing is retarded.

Detonation/knock can also be prevented by going to a higher octane fuel. The octane actually has nothing to do with the power output of the fuel, but rather with its ability to be compressed without spontaneously igniting. Or really how high of a temp it can handle without igniting.

 

excellent information, this is one of those threads that should be mandatory reading..... "sdhotwn" thanks for your work and passing on good information.

 

If you can design something based your R&D and create something like a pocketlogger for the 4g9x guys, you'll be a rich man.

 

Now you got me thinking because I do know enough, and have enough experience with microcontroller based systems to design something that could possibly do that. I'll have to start brainstorming and thinking on a design to do that.

What would we all want? AFR, timing, exhaust temp, ??

It'd probably be a PC serial interface to download it... not sure.. but yeah.. hmm.. damn.. now that I have free time I can spend it doing other things

No guarantees though.. and it'd take a couple months probably...

Later,

Steve