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Author Topic:   Spark plug heat range ??
DirtDobber
Member
posted June 10, 2002 05:17 PM
Although I am running in the pure stock class I am wondering what the advantages are to changing heat ranges on the spark plugs.
I was asked this weekend what range I was running AC 45 and was told to change to 42. That seems cold I think.!?
Pure stock 350 chevy.


BayouGent
Member
posted June 11, 2002 12:39 AM
Personally I've only ran the colder plugs in higher compression engines. A stock compression chevy 350 has always ran just fine for me with a 44 or 45 in it. I usually run the 45's if the compression is in the 9.0:1 range in 44's in the 10:1 range. The stock chevy vette and Z28 engines in the 60's with 11:1 were running ac delco C43's. Of course I'm always willing to try new things too if someone knowledgable suggests it. No such thing as learning enough new tricks in my book.


smayo964
Member
posted June 11, 2002 07:09 AM
Hey guys. One plug that I tried a couple years ago and ended running ever since without any problems is the Champion Truck plug (gold and black). I run either the heavy duty or standard plug for a SB400. Never fouled one or had one give up on me, etc. The standard plug has the longer electrode, which helps on the compression side. The heavy duty is recessed to run colder. I've run both on a SB400 with 305 heads (major compression) on a stock flat top street stock and didn't have any problems. Worked great in my 350's also.

[This message has been edited by smayo964 (edited June 11, 2002).]

DirtDobber
Member
posted June 13, 2002 12:23 PM
Thanks! What part number are you runing in those Champ Plugs?


YAZ
Member
posted June 17, 2002 10:25 PM
I RUN 43 IN MY PURE STOCK.
I TRIED THE RAPID FIRES, BUT
I LIKE THE 43 BETTER. PLUS THERE
ALOT CHEAPER.


smayo964
Member
posted June 18, 2002 09:12 PM
Yo Dobber. Finally remembered to look at those plug numbers. The SB400 regular duty plug is #4025. This plug has the longer electrode. The SB400 heavy duty is #4113. The eletrode projection on this plug is just about 1/16" above the body of the threads. Hope this helps.


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