Points and Plugs
Thread Starter
Burning Brakes
Joined: Aug 2005
Posts: 751
Likes: 0
From: Lufkin Texas
Points and Plugs
First let me ask I have a 72 it has a 400 small block in it the spark plugs in it now are an autolite 145. It has an accell distributor I think the points are under a plate with 3 allen screws, I think it must have points because their is a external coil. I am going to replace it with a electronic distributor that has the cable drive for the tach, what about the sparkplugs? Do i need a hotter plug or something? I was thinking about going with the autolite 26 if it will fit.
Thanks
Thanks
Drifting
Joined: Dec 2004
Posts: 1,345
Likes: 3
A lot of electronic ignition systems use external coils, so you can't use that to determine what you have. My MSD billet tach drive distributor uses an external coil for example.
The distributor and triggering method has nothing to do with the heat range of the plugs with the possible exception that with a "hot" electronic system you may be able to stand a little colder plug without fouling them out at idle or in traffic.
Your heat range depends on how radical your engine is built. In AC ranges most small blocks use "44" heat range with some mild engines using "45". When you start into 350-350s or 350-370s (CID-HP) you ususally need "43" plugs, possibly "42s".
Too cold a plug can foul and too hot a plug can burn a piston or preignite your compressed charge killing high load high rpm power.
The distributor and triggering method has nothing to do with the heat range of the plugs with the possible exception that with a "hot" electronic system you may be able to stand a little colder plug without fouling them out at idle or in traffic.
Your heat range depends on how radical your engine is built. In AC ranges most small blocks use "44" heat range with some mild engines using "45". When you start into 350-350s or 350-370s (CID-HP) you ususally need "43" plugs, possibly "42s".
Too cold a plug can foul and too hot a plug can burn a piston or preignite your compressed charge killing high load high rpm power.
Thread Starter
Burning Brakes
Joined: Aug 2005
Posts: 751
Likes: 0
From: Lufkin Texas
Thanks for the advice 
A lot of electronic ignition systems use external coils, so you can't use that to determine what you have. My MSD billet tach drive distributor uses an external coil for example.
The distributor and triggering method has nothing to do with the heat range of the plugs with the possible exception that with a "hot" electronic system you may be able to stand a little colder plug without fouling them out at idle or in traffic.
Your heat range depends on how radical your engine is built. In AC ranges most small blocks use "44" heat range with some mild engines using "45". When you start into 350-350s or 350-370s (CID-HP) you ususally need "43" plugs, possibly "42s".
Too cold a plug can foul and too hot a plug can burn a piston or preignite your compressed charge killing high load high rpm power.
The distributor and triggering method has nothing to do with the heat range of the plugs with the possible exception that with a "hot" electronic system you may be able to stand a little colder plug without fouling them out at idle or in traffic.
Your heat range depends on how radical your engine is built. In AC ranges most small blocks use "44" heat range with some mild engines using "45". When you start into 350-350s or 350-370s (CID-HP) you ususally need "43" plugs, possibly "42s".
Too cold a plug can foul and too hot a plug can burn a piston or preignite your compressed charge killing high load high rpm power.
