<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px"><div id="yui_3_16_0_1_1440427035978_2698"><span>Asa,</span></div><div id="yui_3_16_0_1_1440427035978_2815"><span></span><br></div><div id="yui_3_16_0_1_1440427035978_2817" dir="ltr"><span id="yui_3_16_0_1_1440427035978_2816">I'm running Autolite 3910 at SSCC. For the street I use 3923. I have A3 heads and 11:1 CR.</span></div><div id="yui_3_16_0_1_1440427035978_2818" dir="ltr"><span></span><br></div><div id="yui_3_16_0_1_1440427035978_2819" dir="ltr"><span>Mark</span></div> <br><div class="qtdSeparateBR"><br><br></div><div class="yahoo_quoted" style="display: block;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 12px;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div dir="ltr"> <font face="Arial" size="2"> On Monday, August 24, 2015 12:17 AM, Asa Jay Laughton via TPR <tpr@teampanteraracing.com> wrote:<br> </font> </div> <br><br> <div class="y_msg_container">Are any of you running colder spark plugs in your souped up engines?<br><br>I pulled the plugs on my Pantera today and cracked one in the process, <br>and found another one cracked (that I don't think I did on the way out).<br><br>Since I'm buying new spark plugs I did some investigation with regard to <br>heat ranges. I typically use NGK UR4 V-Groove spark plugs. The number <br>4 is the heat range, and that's the proper range for a stock engine. <br>However, NGK recommends going one range colder for every 75-100 HP <br>increase. Now, I'm not saying I've put another 100 horse onto my <br>engine, but 50 to 75 maybe? Perhaps, but then again maybe not, I don't <br>honestly know.<br><br>So before I go off and buy plugs in a one colder range, I thought I'd <br>ask the collective experience of those on the list.<br><br>Also, it looks like the spark plug wires I got are for the male towers <br>on the cap. Mine is female and the only way for me to go to the male <br>cap is to go to the larger Duraspark cap. I had one on the shelf from <br>the Mach I and test fit it on the Pantera. It looks like I can get it <br>on and still have sufficient clearance to the firewall. I went with 8mm <br>wires and forgot most of the time those only come for male towers on <br>distributor caps. Oh well.<br><br>I used the borescope on all the cylinders today. It's hard getting it <br>snaked around to inspect the entire piston surface since the spark plug <br>hole comes in at an angle. Overall I think the pistons are okay. They <br>appear to have a black sooty appearance; but do look a little wet, <br>probably from the over-rich mixture I'm running. I didn't detect what I <br>would think melting of the pistons would look like.<br><br>The plugs all appeared to be in good shape, lightly brown and sooty.<br><br>One interesting thing. I took the valve covers off to re-check rocker <br>arm clearances. Number 5 intake was tight, and that seemed to be very <br>odd. I double checked the crank position and the other valves I was <br>checking, of them all, number 5 was tight and I thought that was really <br>weird. I've not had any back-firing through the intake, but as tight as <br>this one seemed, I would think I should have.<br><br>I re-adjusted it and will crank the engine tomorrow for the compression <br>testing and watch that valve to see if it's acting properly or not.<br><br>I didn't get near as far as I hoped today. Maybe tomorrow I can get it <br>all put back together, again.<br><br>Yes, again. I got the oil temp sender in place and oil added and <br>checked just in time for Sam and I to go to the car show yesterday. <br>Then it was off for our haircuts and then back home. Today after <br>Church, I tore into it again. <sigh> Seems like I'll never get done, <br>but I'm working at it a little at a time.<br><br>Asa Jay<br><br>-- <br>Asa Jay Laughton - W7TSC, MSgt, USAFR, Retired<br>& Shelley Marie<br>Spokane, WA<br>******************************<br><a href="http://www.racingagainstautism.com/" target="_blank">http://www.racingagainstautism.com</a><br><a href="http://www.teampanteraracing.com/" target="_blank">http://www.teampanteraracing.com</a><br><a href="http://facebook.com/racingagainstautism" target="_blank">http://facebook.com/racingagainstautism</a><br><br><br>_______________________________________________<br>TPR mailing list<br><a href="mailto:TPR@teampanteraracing.com" ymailto="mailto:TPR@teampanteraracing.com">TPR@teampanteraracing.com</a><br><a href="http://teampanteraracing.com/mailman/listinfo/tpr_teampanteraracing.com" target="_blank">http://teampanteraracing.com/mailman/listinfo/tpr_teampanteraracing.com</a><br><br><br></div> </div> </div> </div></div></body></html>