StevenB L98/LS1

Ive done some research and i have come across confused on some things. I have found 2 different part numbers on the same part. I ordered a MSD Ignition box, which i am hoping is the correct one, part # 6200. Off msds website though it says it takes a 6220.

Now at my work it calls for a 6200, so i am confused on that. my buddy ran an msd on his 90 L98 TA and he was told to run a colder plug. Now he doesnt remember what he put in it, but is there any suggestions or lead me to what i could use for colder plugs.

I already have the GM HEI coil, which leads me to 2 other questions. I dont want to take the distributor out, what cap and rotor can i run, or which msd cap and rotor is it? Because i couldnt find one on the computer system at work, so i was wondering if any can lead to a part number of some kind.

Which also leads me to my last question, they say the msd wires are universal 8.5 mm in black or red or blue. Is there any difference? Which would you use? Because they say the wires wont work with a mallory cap and rotor button which is all that i could find at work. It said it has to be the HEI cap.

Rauch

I'm assuming that you meant 6420 instead of 6220, (They don't make a 6220).

From that standpoint, the 6420 is the 6AL while the 6200 is the 6A. Both are nearly identical with the exception of certain features. Both will work as well. The specifications for the two are the same as well, the only difference being the Rev Controller on the 6AL.

Of course, since the sparks produced by the MSD are hotter, people would think it'd be wise to run a colder plug. That's half the truth. While you want to run a colder plug, MSD says to run a plug that's a step or two colder than your OEM plugs. They also recommend using plain copper plugs, which other users on this forum even use copper plugs on their race engines, specifically talking about AlkyIROC, who told me to run a copper plug as well.

Since the sparks produced are stronger, you'd want to gap your plugs a little further as well. MSD recommends starting with .005 increments until the engine runs smooth. You wouldn't want to do too much adjusting to plugs though, as the electrode could potentially break off due to weakening of the metal. So perhaps, you should have another set on hand once you get the perfect gap.

Assuming you're using the GM HEI Coil, you have the GM HEI Distributor as well? You have several choices for the caps/rotor sets. All just have different features, accessories, and mostly price.

-8500
-8501
-8502
-8416
-84111
-84023

Which is best? It all depends on what you need it for. Most of these are just different features and sets. There's also a set that includes the 6AL - P/N 8500.

The difference in those wires is just color. Although, personally, I wouldn't recommend "universal" plugs. You'll end up like me when I bought my car. Extremely long wires that are zip tied together at various points and look absolutely horrible. Look into the GM Set - 31369.

StevenB L98/LS1

Sorry typo there, i ordered the 6200 box. And remind was the number on the plug higher or lower to be colder? And my buddy ran a step down on his plugs, idled perfect, quick response, and took off like a rocket. So just like standard ac delcos would work? Or autolite coppers? I thought i was gonna have to run like a colder platinum plug lol. I guess i just need to figure out the cap situation. i dont care really i just want everything to do the job right done. And anything else i need to know, other than the wiring the box up which my buddy already knows how to do.

StevenB L98/LS1

ok so i think im going to work with the 25 autolite copper plugs, and the 31369 wires, and i found the cap and rotor at a second source website we offer at work once i looked through the catalog for it, only 33 bucks for i went ahead and ordered it.