importwarrior Posted July 3, 2005 Report Share Posted July 3, 2005 that is great info.i never thought about it but the pics explain alot! i will have to check the thread depth when i change my head gasket. Link to comment Share on other sites More sharing options...
4NMOPAR Posted July 29, 2005 Report Share Posted July 29, 2005 yeah awesome info guys, I learn something new each day I'm here ! Link to comment Share on other sites More sharing options...
Banky Posted October 4, 2005 Report Share Posted October 4, 2005 What do you folks think of these? 3 electrodes: http://www.paragon-products.com/photos/BOSCH_WR7DTC-2.jpg Link to comment Share on other sites More sharing options...
artinist Posted October 5, 2005 Author Report Share Posted October 5, 2005 when it comes to spark plugs its good to be racist. bosch for germans and NGK/ND for japs. Link to comment Share on other sites More sharing options...
B.K. Posted October 29, 2005 Report Share Posted October 29, 2005 I HAVE A BRAN NEW MARNAL HEAD THAT I WILL BE PUTTING ON THE QUEST I WILL CHECK IT OUT, I AM GOING TO BE USING THE IRIDIUM NGKS Link to comment Share on other sites More sharing options...
Richie_Rich Posted October 29, 2005 Report Share Posted October 29, 2005 Please post a pic with your Marnal-AMC head if that's the one you have. I forgot about this thread when I had MrDodge's engine apart. Here's a picture of the Marnal-India head.It looks pretty good as far as the spark plug projection.http://www.mostarquests.com/albums/userpics/10009/DSCF0219.JPG Link to comment Share on other sites More sharing options...
artinist Posted October 30, 2005 Author Report Share Posted October 30, 2005 yea, that combusion chamber is way different that the AMC Link to comment Share on other sites More sharing options...
bad2theBone Posted November 13, 2005 Report Share Posted November 13, 2005 what type of marnel head is the best made, is it from india, usa, brasil, spain, South America, China or anyother country made, its that true the best quality and endurance material is the one from spain, please correct me if i'm wrong. Is it possible using the Marnel head from spain, with the Stock Starion or conquest TBI Injection system for the moment as daily driving When I get the marnel head in here can i just make the Porting job or its also very important to have the polish job as well. How much is the retail price for a porting and polish job done. or at least just the porting. Doing the polish job on the marnel head after porting, it will make any difference, i'm just asking because i only read that many people is doing the porting job but i haven't see at this moment anyone doing the polish job as well on any head. i just want to know whats the deal with that, in not doing the polish work, may be is more expensive +++$$$ in doing the polish work. http://images.amazon.com/images/G/01/video/stills/star-wars/sw3-92534-r.l.jpg Link to comment Share on other sites More sharing options...
TurboRaider Posted December 9, 2005 Report Share Posted December 9, 2005 I dont think the shroud or the plugs threaded end run very hot at all. Look at the exhaust valve, nice tan collor becuase it gets hot. Look at the intake valve... dark because it stays cool. Same with the shroud and the plug body, if they were gettging hot you would seem them turn a lighter color. Kevin Link to comment Share on other sites More sharing options...
Technology Posted February 2, 2006 Report Share Posted February 2, 2006 I dont think the shroud or the plugs threaded end run very hot at all. Look at the exhaust valve, nice tan collor becuase it gets hot. Look at the intake valve... dark because it stays cool. Same with the shroud and the plug body, if they were gettging hot you would seem them turn a lighter color. Kevin or is it because they are made of different metal. everything is hot in a combustion chamber, it doesn't have to be discolored from heat to be hot enough to cause premature detonation. i'm gonna check this out.. Art - what does a port job like that do to the compression, quench zone, etc. ? does it thin it out excessively around any water jackets? Link to comment Share on other sites More sharing options...
artinist Posted February 2, 2006 Author Report Share Posted February 2, 2006 not much material was taken out the combustion chamber. just the sharp points were removed mostly. anothing thing with the exposed threads. if carbon builds up on those threads, it could easily damage the threads on the head if you remove the plug. Link to comment Share on other sites More sharing options...
TurboRaider Posted March 17, 2006 Report Share Posted March 17, 2006 I dont think the shroud or the plugs threaded end run very hot at all. Look at the exhaust valve, nice tan collor becuase it gets hot. Look at the intake valve... dark because it stays cool. Same with the shroud and the plug body, if they were getting hot you would seem them turn a lighter color. Kevin or is it because they are made of different metal. everything is hot in a combustion chamber, it doesn't have to be discolored from heat to be hot enough to cause premature detonation. i'm gonna check this out.. Art - what does a port job like that do to the compression, quench zone, etc. ? does it thin it out excessively around any water jackets? Its the combustions deposits that turn differant colors as the get hotter, not the metals. Once you have a few miles on a motor there are not many bare metal surfaces. So if the plugs threaded section is dark with some oiley deposits on it it it not getting hot enough to burn the oil away. A good example of this is the valves. The exhaust valve runs hot and you wons see any dark oily depostis on it. The intake valve runs a lot cooler and looks darker and oil and fuel can cake onto the backside. Basicly its like reading plugs, white deposits = hot, dark = cold because it never got hot enough to burn the oil off. If the part is not hot enough to burn oil off of it its not a big factor for detonation, at lest compared to the exhaust valve thats hundres of degrees hotter. Cooler running exhaust valves can redcue octane requirments. Since octane is a limiting factor for the amount of boost and HP you can can make finding a way of lower its temperature may help. I wonder how sodium filled valves would work? Kevin C Link to comment Share on other sites More sharing options...
Technology Posted April 9, 2006 Report Share Posted April 9, 2006 well, i tried the stupid method for measuring plug depth into the head. i took a short peice of coat hanger and bent the end 90 degrees and held it in the plug hole and pulled back so it was against the edge inside. then i held my finger against the base on the outside, then took it out, and measured that against the spark plug. it was the same length, but i have no idea if i'm holding the hanger peice in the right spot for a semi-acurate measure. my head is on my car though. i have an AMC head and i think it's ok. but i'd like someone else to try or just tell me the smart way to do it, and i'll do it. Link to comment Share on other sites More sharing options...
AUstarion VR4 Posted October 17, 2006 Report Share Posted October 17, 2006 Ahhh, we had the same problem here in Australia on our race car, turned out it B7ES plugs R the correct units, they R full reach but the centre electrode isn't exposed, NGK web site has more info on BCP*...B7ES etc. Link to comment Share on other sites More sharing options...
tsiconquest88 Posted January 7, 2008 Report Share Posted January 7, 2008 (edited) i somehow missed this whole post along the way lol but i have been using the bpr8es's in every plug change over the years in my cars, unfortunately i never looked at this BUT i can say one thing all the threads are clean as the rest no carbon so i would assume that the plugs have never been close into the chamber, and i have been using marnel AMC heads all along. just some 2.6 cents on this post that has been dead a while lol Edited April 2, 2009 by tsiconquest88 Link to comment Share on other sites More sharing options...
roketa Posted March 20, 2008 Report Share Posted March 20, 2008 Art, I own the car that Kelly has been working on. I bought some bushings etc from you. I found out you have an adjustable cam gear on your car. I believe it is a Starconquer Industries product. Can you give me some more information on the gear? Also when I was doing tuning we would usually go to a 1 range colder plug as we increased the boost. With boost comes heat. If you were running 20 psi boost, what short plug would you use. I would appreciate your help. Thanks, Roketa George Z Link to comment Share on other sites More sharing options...
artinist Posted March 25, 2008 Author Report Share Posted March 25, 2008 well the cam gear is just a stock replacement unit. for the plugs i wouldnt get anything short unless you are sure they are sticking out into the chamber. Link to comment Share on other sites More sharing options...
VICE Posted December 6, 2008 Report Share Posted December 6, 2008 (edited) I'm running a marnal head and I usually use the NGK's OEM recommended $2.13 plugs in most my plug changes, I have used the Rx-7 plugs peeps talked about and I think they looked like burned :eek1bluegreen: afterwards.. I dunno I'm not one to be able to tell but that's my opinion, also I would like to know if the Iridium plugs are worth the almost $8's ? I have never used them, are they any good or am I ok sticking wit the lower priced NGK's, is that they are too short for the marnel tho will that be a problem.. :party0035: Edited December 6, 2008 by VICE Link to comment Share on other sites More sharing options...
soulja620 Posted March 2, 2009 Report Share Posted March 2, 2009 bump for an answer??? Link to comment Share on other sites More sharing options...
artinist Posted April 2, 2009 Author Report Share Posted April 2, 2009 I have no idea what a burned plug looks like. they are in fire all day after all. i melted a set of splifires if thats what you mean. burned is probably ok. i have no idea on iridiums, never used them. as long as there is no misfire or pinging, that usualy means the plugs are not a source of problem or power gain. Link to comment Share on other sites More sharing options...
Drive-By Posted February 6, 2010 Report Share Posted February 6, 2010 Hmm I have the TEP head (Street Performance Head) with port and polish. This thread is very interesting as I notice no one has mentioned DENSO plugs ? I got the DENSO's for my build as they are basically the HKS plugs but without the HKS logo on. Anyway I hadn't given the length any thought until now. The pics in the thread won't work for me, have the hosts been lost? Link to comment Share on other sites More sharing options...
Fuze Posted September 15, 2011 Report Share Posted September 15, 2011 (edited) Good source below, you can look up the PN's and see images with a ruler diagram. No guesswork on the length, etc. Stock NGK plug BPR6ES: http://www.sparkplugs.co.uk/pages/database/plug-detail-ccp.asp?partno=BPR6ES Shorter NGK BPR7HS: http://www.sparkplugs.co.uk/pages/database/plug-detail-ccp.asp?partno=BPR7HS You can see the specs, and close up shots even. http://www.sparkplugs.co.uk/index.htm Edited September 15, 2011 by Fuze Link to comment Share on other sites More sharing options...
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