Guest Posted February 26, 2002 Share Posted February 26, 2002 Can anyone tell me how to properly choose the heat range for spark plugs? Is there a tutorial on the web somewhere? Also, is there a guide somewhere which shows the heat ranges for the different plug manufaturers and how the part numbers correspond to the heat range? In my '71, the plugs are a little black even though judging be the exhaust, the car is not running rich. I'm wondering if the plugs are running a bit cold but I don't know how to check this or what plugs I should use instead. Thanks in advance for the help. Link to comment Share on other sites More sharing options...
Guest Posted February 26, 2002 Share Posted February 26, 2002 Give me some info on your set up. some combos will leave a lite coating of black soot on the plugs. unleaded fuels don't "read" on the plugs like in the old leaded days. carb'ed non computer engines won't read like a late model FI will. late FI's run so lean that if a carb'ed set run that lean it would damage the engine. the computers do a lot of timing changes to stop detonation the whole time the thing is running. Link to comment Share on other sites More sharing options...
Guest Posted February 26, 2002 Share Posted February 26, 2002 This is what I got: -400 small block with flat top pistons (approx. 9.5:1) and stock rods. -Edelbrock Performer RPM intake, heads, cam and 1406 carb (600 cfm). Cam is installed straight-up. - 1 5/8" headers into 3" pipes with cross-over. - MSD 6A ignition module with a Pertronix trigger. I don't remember what the plugs are but I can check tonight. I'm running 93 octane unleaded. Timing is 8 degrees at idle with approx 36 degrees total. ------------------ Huibert http://home.twmi.rr.com/hmees/monte_index.htm Link to comment Share on other sites More sharing options...
Andreas Posted February 26, 2002 Share Posted February 26, 2002 Check this out: http://www.edelbrock.com/automotive/sparkplugs.html http://www.motocross.com/motoprof/moto/mcycle/plug2/plug2.htm http://www.splitfire.com/plugtips.htm http://www.sa750.com/plugs/plugs.htm http://www.in.net/~eholman/ngkplugs.html http://www.ngksparkplugs.com/techinfo/spark_plugs/techtips.asp#heat ------------------ 71 Monte 383 "The Full Monte" 86 Monte LS ZZ4 "The Gray Mouse" FOR SALE! Andreas' Monte Carlo Site Member NMCOA, FGMCC (Event Coordinator) --------------------------------------- "It ain't a car if it's not a Monte" Link to comment Share on other sites More sharing options...
Guest Posted February 27, 2002 Share Posted February 27, 2002 9.5 comp with aluminum heads, step the heat range up one and make sure to use the extended tip verison gap it at .035. should take care of it Rice Racing Link to comment Share on other sites More sharing options...
Guest Posted February 27, 2002 Share Posted February 27, 2002 Thanks, Rice Racing. One thing I forgot to mention, I also use a MSD Blaster 2 coil. Would you still stick with the .035 gap or would you go larger? Wouldn't the higher voltage allow for a larger gap or is there no advantage? Is there a particular brand which you would recommend? What about Platinum? When you say "extended tip", do you mean extended versus stock plugs? Thanks again. ------------------ Huibert http://home.twmi.rr.com/hmees/monte_index.htm Link to comment Share on other sites More sharing options...
Guest Posted February 27, 2002 Share Posted February 27, 2002 Yes even with the MSD coil stick with the .035 gap. The extended tip means the electrode is further out of the shell, for a good example next time you go to the parts store look at an R44T ac plug its standard then look at an R44TS it is an extended tip. the 6 series boxes are better than stock but even they are not a "hot" ignition, besides it's not the size of the spark it's the intesity of the the spark that matters. a small "hot" spark will ignite the mix far better than a large "warm" spark. In the race stuff with the race only MSD set up, 7AL3 box, pro power coil, etc. etc. I only use .035 gap any larger and it will mis fire at high rpm. granted my mix is harder to fire 14.5 to 1 compression, but the principal is still the same. the NGK V-POWERS work great. Rice Racing "Don" [This message has been edited by Rice Racing (edited 02-27-2002).] [This message has been edited by Rice Racing (edited 02-27-2002).] Link to comment Share on other sites More sharing options...
Guest Posted March 1, 2002 Share Posted March 1, 2002 You guys are great! Thanks for all the help. ------------------ Huibert http://home.twmi.rr.com/hmees/monte_index.htm Link to comment Share on other sites More sharing options...
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