Would an egt help? Not sure if Im rich with afr.

[quartermilecamel]

Reading up on egt has me wondering if getting one would help. 1st issue is the probe has to be 3 inches from the exhaust port, didnt know that. That means either get a 1 channel egt or the 4 channel egt guage. What do most people use? Primary reason for this post is when I accidentially unhooked a plug wire, I noticed the afr meter went lean. Got me to wondering if I really am running rich, which I think I am but not sure. I saw the 4 channel egt guage in a thread for 250 bucks. Is there a way to tell if you have un burnt/unused gas with an afr? I could just get the egt anyway and further my tuning capabilities.
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[jhoefer]

If you have a cylinder misfiring (like pulling the plug wire), you'll get lean AFR's (too much air, not enough fuel) because the oxygen in that cylinder is not being consumed by combustion.

[miniman82]

Personally if you need an EGT meter to tell you about a misfire, you don't know enough to be tuning but that's just me. Not a slam, just saying.

To me, EGT is really only useful for tuning the ignition system. That's because once you dial in the fuel system with the wideband, you want to make sure your timing is not too late since it usually shows up as high EGT near the port. Honestly though if you're in the ballpark, EGT should not be too far out of wack. I measure 1500*F on boost all the time, people say it's too high but what do they know.

A dyno is a far better instrument, because it gives you HP and brake specific fuel consumption. Those are much better tuning metrics than EGT.
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[quartermilecamel]

Ok so egt really isnt a major help for me then. Curious though, as Ive been reading loads of threads on egt but still the theory of you want to be lean off peak which is better than rich off peak. How does one define peak? Does that mean you have to fiddle fart around trying all kinds of shit to see how high you can get egt or is there a standard "peak" that every one uses? Amost sounds like egt is for people that have all the time in the world to try jetting/timing combos for the highest egt. I still remember johns discussion/thread on jetting a carb too rich so that the gas is still burning way after the commustioin cycle and the afr meter reads lean so they richen it some more. Was hoping egt would really help. Although you guys helped me decide I dont need egt.
Ok so I understand I think. If the timing is too late, then the gas will still be burning maybe a bit more and hence the high egt. What would you do if it was a high egt? advance the timing? Or, lean it out?
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Waiting for santa to drop off funky green. I can wish can't I????

[[email protected]]

using a wideband is easier.

You can actually use either, if you have a chart to reference, and know how to read it. If you lean the mix and EGT goes up, you are ROP. If EGT goes down you are LOP.

With EGT you have to figure out where you are by using the chart, with a wideband you already know.
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