spark plugs
Safety Car
Joined: Sep 2005
Posts: 4,239
Likes: 654
From: Orange County Ca
If you use the correct heat range, I don't think you will notice any difference in any brand of spark plug in any thing short of a race car. Over the last 40 years, I've used most all major brands, and a few gimmic plugs also. I generally buy the ones on sale. A couple of months ago regular Autolite plugs were on sale for $.49 after rebate. They work fine.
CF Community Team
Joined: Oct 2004
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From: Cape Cod, Mass.
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I use the AC R43XLS on my big block but did try the SplitFire plugs on my 65 and I thought they were junk. The car seemed to lose low end torque. They were Ok at high RPM's but I didn't like the feeling of torque loss. Most mechanically inclined friends of mine agree that they are junk.
Pro
Joined: Mar 2002
Posts: 511
Likes: 0
From: St. Louis MO
I use autolite 3924's, which are the counter part to the r43xls except that they use a 5/8 spark plug socket rathter than the 13/16. Makes it easier to get the plug in with the 2.25" header priamary tubes on my stahl side pipe headers. I'd rather use delco plugs but the guys at the autoparts store can't seem to figure out how to cross the 3924's to the delco plug with the 5/8 socket.
a plug is a plug, unless you get into the resistor and non resistor styles. You only get one spark (well if running msd after 3000 r's its only one spark) per ignition event so multiple ground straps don't really make sense to me. How are you going to get that spark to split, its going to head to the closest ground lug 9 times out of 10. and then you have the bosch +4, I have to ask WHY?! Platnium and the other High dollar plugs are just that high dollar. They may last a little longer but eventually they will break down too.
I change my plug alot more often than most people just because, so the cheap plugs are my preference.
a plug is a plug, unless you get into the resistor and non resistor styles. You only get one spark (well if running msd after 3000 r's its only one spark) per ignition event so multiple ground straps don't really make sense to me. How are you going to get that spark to split, its going to head to the closest ground lug 9 times out of 10. and then you have the bosch +4, I have to ask WHY?! Platnium and the other High dollar plugs are just that high dollar. They may last a little longer but eventually they will break down too.
I change my plug alot more often than most people just because, so the cheap plugs are my preference.
