Irridium plugs for a 502 MPI motor???????
04-22-2016, 11:30 AM
#11
Registered
Just as a little FYI: the M (marine) series have stainless (or nickel plated) for metal (threads + body) so they won't rust as much as the standard R43T's.
Not sure on commercial, but easy to tell. If threads are black on any AcDelco, they are normal steel. If they are shiny they are SS or nickel plated.
If they are steel (black) just don't let them stay on motor forever....LOL. And obviously, salt water use can make hem corrode real quick.
That's all.
Edit in: Have an Oreilly's ? Online shows most physical Oreilly stores carry the MR43T's.
Not sure on commercial, but easy to tell. If threads are black on any AcDelco, they are normal steel. If they are shiny they are SS or nickel plated.
If they are steel (black) just don't let them stay on motor forever....LOL. And obviously, salt water use can make hem corrode real quick.
That's all.
Edit in: Have an Oreilly's ? Online shows most physical Oreilly stores carry the MR43T's.
A little dab of anti seize should cure that. And no salt here in desert, except on my forehead.
04-22-2016, 12:19 PM
#12
Registered
VIP Member
i agree with Bondo - the fancy stuff is a waste of money, and in my opinion, more risky as well. The plain larger ground straps are safer imo.
I also agree with the other guys below ....nothing wrong with the MR43T, but for decades ive run the Autolite 23 which is a "projected" tip. It sticks more out of the plug and therefore gets cooled off more by the incoming gases/fuel.
Now the 23 is 2 ranges colder, but, i have never had one misfire from idling/loading up even for a couple hours at a time. And i often run mine hard so i feel much much safer with a colder plug. I think the 25 which is the actual recommended one, would be too hot for running hard. If you dont hardly ever run WOT, then maybe go to the 24 which is in the middle.
These are NOT the nickel plated. If you dont have corrosion issues that's fine...they are cheap. If you do, then go with the Autolite racing plug version of the projected tip, and they are nickel plated, which is an AR23 for me. They also make the AR24 and the AR25 but i would be careful of the hotter plugs.
I also agree with the other guys below ....nothing wrong with the MR43T, but for decades ive run the Autolite 23 which is a "projected" tip. It sticks more out of the plug and therefore gets cooled off more by the incoming gases/fuel.
Now the 23 is 2 ranges colder, but, i have never had one misfire from idling/loading up even for a couple hours at a time. And i often run mine hard so i feel much much safer with a colder plug. I think the 25 which is the actual recommended one, would be too hot for running hard. If you dont hardly ever run WOT, then maybe go to the 24 which is in the middle.
These are NOT the nickel plated. If you dont have corrosion issues that's fine...they are cheap. If you do, then go with the Autolite racing plug version of the projected tip, and they are nickel plated, which is an AR23 for me. They also make the AR24 and the AR25 but i would be careful of the hotter plugs.
04-22-2016, 01:49 PM
#14
Registered
Sweet! It's nice having options, if I make it to town today I'll see what I can get , although I missed the early window so the river has a ton of runoff debris now.
04-22-2016, 02:19 PM
#15
Registered
Charter Member
04-24-2016, 01:21 AM
#18
Registered
Thread Starter
Good info here guys and thanks for the input.
Fancy stuff is not my interest but practical info and experience with products helps a lot. I like delco but in high performance we ran NGK's a lot for various conditions. Nice to know they work here as well.
Fancy stuff is not my interest but practical info and experience with products helps a lot. I like delco but in high performance we ran NGK's a lot for various conditions. Nice to know they work here as well.
04-24-2016, 08:13 AM
#19
Registered
iTrader: (1)
For stock GM motors, it's very hard to beat the factory GM Ac Delco plug. Very, very hard.
Once engine is mod'd , it does not seem as critical since heat ranges sometimes need to be changed anyway, and obviously the engine'sare not the same as what GM tuned/rigged for.
If you are one who reads spark plugs for tuning purposes or what have you, the regular AC Delco's and Autolites have black threads and etc. Makes thes very to hard to read. Marine AC Delco's, all NGK's, all Champions, have 'bright nickel / Stainless' colored threads and etc which makes reading plugs very easy.
A special note on NGK's, for the ones for gasketed applications, NGK uses a different style washer/gasket. It is soft and crushes. I actually love them ! However, I cannot tell you how many people stop turning them in when they feel the initial resistance, which leaves them unknowingly loose. GM/Merc V8's typically use a tapered plug (no gasket / washer) so there is no worry there - just mentioning this as many engines do.
Once engine is mod'd , it does not seem as critical since heat ranges sometimes need to be changed anyway, and obviously the engine'sare not the same as what GM tuned/rigged for.
If you are one who reads spark plugs for tuning purposes or what have you, the regular AC Delco's and Autolites have black threads and etc. Makes thes very to hard to read. Marine AC Delco's, all NGK's, all Champions, have 'bright nickel / Stainless' colored threads and etc which makes reading plugs very easy.
A special note on NGK's, for the ones for gasketed applications, NGK uses a different style washer/gasket. It is soft and crushes. I actually love them ! However, I cannot tell you how many people stop turning them in when they feel the initial resistance, which leaves them unknowingly loose. GM/Merc V8's typically use a tapered plug (no gasket / washer) so there is no worry there - just mentioning this as many engines do.
