| at its leanest point which is a far cry from being too lean. I've seen dynocharts of other vehicles tuned by other respected tuners which were pushing mixtures even leaner than this. For what it is worth, I run ~12.0-12.5:1 mix in my personal Z on PUMPFUEL at 19psi and my car makes 540RWHP and 520RWTQ and I beat the mess out of it daily. If you think 12.2 is too lean then once again, there's nothing I can tell you. Not to mention, that is only at one very small band of RPM - 0.2 A/F points constitutes only a 2% difference from 12.0:1 in the fueling maps, for whatever you may think that is worth. Fact is, 12.0:1 A/F is a very safe mixture to run and has far more headroom than only 2% built into it. 
As for the interpretation on the plug heat range, there appears to be a good deal of confusion coming from the interpretation of the documentation that NGK provides. Here is the text of which is being misinterpreted:
The insulator nose length is the distance from the firing tip of the insulator to the point where insulator meets the metal shell. Since the insulator tip is the hottest part of the spark plug, the tip temperature is a primary factor in pre-ignition and fouling. Whether the spark plugs are fitted in a lawnmower, boat, or a race car, the spark plug tip temperature must remain between 500C-850°C. If the tip temperature is lower than 500°C, the insulator area surrounding the center electrode will not be hot enough to burn off carbon and combustion chamber deposits. These accumulated deposits can result in spark plug fouling leading to misfire. If the tip temperature is higher than 850°C the spark plug will overheat which may cause the ceramic around the center electrode to blister and the electrodes to melt. This may lead to pre-ignition/detonation and expensive engine damage. In identical spark plug types, the difference from one heat range to the next is the ability to remove approximately 70°C to 100°C from the combustion chamber. A projected style spark plug firing tip temperature is increased by 10°C to 20°C.
What is humorous is that the second from last sentence appears to have had a translation fluke. If you read carefully what the entire paragraph is about, it is referring to the temperature of the center electrode/ceramic insulator and not the temperature of the combustion gases. The temperature of the combustion event is dependent on the energy released in the chemical reaction between the fuel and air - and dependent on the air to fuel mixture, compression ratio, and ignition timing. The temperature of the combustion event is NOT dependent on the heat range of plug you use. The heat range of a plug denotes how much heat the plug's center electrode will be able to sink into the head, thereby controlling the operating temperature of the center electrode. It seems that you are misinterpreting that sentence into thinking that the plug is actually making a difference on how much heat is generated in the cylinder in the combustion process, and that is incorrect. The temperature of the combustion event in your engine was so great that it was able to melt inconel - the fact that it also melted the steel ground straps on the plugs is of no surprise at all considering inconel melts at a much higher temperature. The plugs had nothing to do with the heat - the heat was because of a really lean mixture, and I'm not talking about a 12.23:1 mixture, I'm talking about a mix well into the 13:1 range. At this point you have added an additional argument that the mixture was too lean on top of too hot of a plug. While I totally agree that if you use too hot of a plug and run the engine too lean it will result in engine damage, what I do not agree on, and have a library of empirical historics to prove it with, is that the 6B plugs are too hot or that a 12.2:1 mix is too lean. As for your interpretation of my efforts to try and help you get the car back together, I am appalled. I offered to do those things for simple sake of trying to help you out in ways that I would have been able to do with the time I had available. The fact you are now using that gesture against me just further reinforces the nature of your character. So, on to the emails. I'm going to simply post them here in succession as they occurred, as reply threads to this original: STarting with the very first: 4/21/2008 Hi Ash,
I wanted to give you some information about my participation in the PINKS ALL OUT event being
held at Raceway Park ([ http://www.racewaypark.com/ ]) on July 26th 2008 and wanted to
know if you would be interested in sponsoring my Z-32. My ride is pretty
complete with the exception of a few last needed parts and a good dual stage tune, so I think you know where I'm going with this. I have attached the
details of my build as well as a couple of pictures. She's a sleeper. I have been drag racing for about 3 years now and prior to the build I ran consistent high 11's on stock turbos and plan on at least mid 10s for the PINKS event. If you are interested in
sponsoring my car by working out some sort of deal on your tune when you come to DE in June, I would be very happy to
promote your business at this event. Vinyl on my car, distributing promotional items,
etc... Think abo ut it and let me know at your greatest convenience. The are many members of the Z
community that can testify to me being a real stand up kind of guy. Thank
you for your time and I look forward to the possibility of working with you as I
head into this event.
PS - You can also go to the raceway park web site to verify that my name is on
the list for this specified event.
Highest Regards, Tony Zapisek (phillyz)
215-964-4018
[ ashspecz.com ]
[ agpowers@bellsouth.net ] Enthusiasts soon understand each other. --W. Irving.
Are you an enthusiast? If you are out to describe the truth, leave elegance to the tailor.
Albert Einstein
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