Too hot of a plug??

[Super73]

Well, I fixed my oiling issue, was pulling oil through the intake with the stock cranck case ventalation and the big ring gap/blow by. It was really hard to read a plug before.

Put new plugs in it today and went for a quick 7-8 mile ride, standing on it once. Here is what the plug looks like that I pulled. Wide band reports AFR is pretty much dead on.

Keep in mind I am on E48 (50/50 mix of 91 and E85). Part throtlle / idle I have a bit leaner than stoich. but look at where the heat mark is at. looks to me like a TR6 is quite a bit too warm for it even on motor.

[bubba353z]

What's your target AFR?

[Super73]

10.5 to 10.7ish..
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[Marv D]

You throw any sort of 'ahol' in the mix (be it Methanol or Ethanol) and plug reading becomes a total black art in my book. In fact I might as well be drinking that ethanol!! I ran a car on VP's M3 methanol for a 'SHORT' time,, no wideband to assist just trying to figure out the plugs. But I was so far off on the tune I had one dead hole and didn't even know it. I'm not sure the standards and tried and true plug reading we know from gasoline apply. Hopefully Vin will pop in with some real expertise,,, bu ti the mean time... My opinion is,,,, trust your wideband. If it doesn't start boiling the cement in the plug and blistering the porcelain,,, I'm not sure I'd worry about it. I had a hard time BUILDING heat in the motor so is the e48 going to be cooling the chamber so much that you need a hot plug to keep the fires lit???
Just my first thought and probably not even worth the 2¢ of fuel it took to type it,, I'd take some 'cruise' timing out of it and see if power suffers, and I bet it will move the heat mark back closer to the bend. We both know it would in a WOT and race fuel hard pull. But what it does on the street........ with a blend of ethanol... Man like I said. I'd trust the wideband and be drinking the ethanol to calm my scattered thoughts. LOL

[Super73]

I trust the wideband as far as AFR goes. I varified mine was accurate with in a given % against a very expensive one on the dyno.

As far as heat range goes, it seems as though the feeling once was to run a hotter plug do to the ethenol. But now it seems as though that idea has diminished and people are reverting back to a more traditional plug temp for Ethenol blends. From what I am understanding, a glow plug is a glow plug, and can't really be good for anything but a diesel fuel at start up.

I am sure there will be a learning curve here, but I can't see a colder plug being a bad thing. Right now, the heat mark is pretty far from where I'd like it to be.

I am less worried about the white lean look on the tip since I know my part throttle is set a little lean (on purpose). Where I need to look is way down in the plug and see what it tells me for WOT, but I can't do that with a street driven plug. I will do that at the track.



If there are others here that run Ethonal Blends (48-85% Ethonal) please let me know what your take is. Thanks