Mostly stock 340 engine what Spark plugs

-
DartSport340

DartSport340

Well-Known Member
Joined
Apr 10, 2008
Messages
199
Reaction score
1
Man this whole SB and 340 thing is still foreign to me lol..I know exactly what plugs my RoadRunner took with the 383 :) but I have no idea what the 340 should take pretty much stock 8.5 comp ratio with a stock grind cam and headers..what should I get/use? Most of my search results turned up guys asking what to run on 10:1 comp ratio engines and strokers..not really anything on what STOCK plug to run ..
 
Thanks, I think I need a Service Manual or something that tells all about this car..I dont even know if they make such a thing though :) . I know they did for my RoadRunner made it real easy to look up stuff and all the torque specs and how to tear it apart and put it back...big difference going from BB to SB though..the Distributor isnt not even in the proper spot :) ..thanks guys for answering all these seemingly routine questions.
 
I was always one to use Champions in my Mopars. Till I couldn't get the
Duster to idle good. Was looking on moparts racing site and seen the guys
using Autolites. I put them in the Duster and haven't had any problems
after that point. Use the Autolites.
 
briankaplan said:
I was always one to use Champions in my Mopars. Till I couldn't get the
Duster to idle good. Was looking on moparts racing site and seen the guys
using Autolites. I put them in the Duster and haven't had any problems
after that point. Use the Autolites.
Click to expand...

oh man champions suck. haven't run them since the 80's..lol


been running autolites all this time. right now i have NGK in my car and they have been great too. saw a lot of guys using the NGK so i figured i'd try them..
 
DartSport340 said:
Thanks, I think I need a Service Manual or something that tells all about this car..I dont even know if they make such a thing though :) . I know they did for my RoadRunner made it real easy to look up stuff and all the torque specs and how to tear it apart and put it back...big difference going from BB to SB though..the Distributor isnt not even in the proper spot :) ..thanks guys for answering all these seemingly routine questions.
Click to expand...

there are a few service manuals for download here.. http://www.forabodiesonly.com/mopar/showthread.php?t=132309&highlight=service+manual
 
Hemiroid said:
Do you have a manual for a 69 Dart Swinger.

Thanks
Kenny
Click to expand...

look through that thread. its down the page some. i would have edited the first post and put all of them in there but for some reason this damn site only allows so much time to edit things.
 
I run NGK plugs in both of my 340 engines, forget the number but I can check.
 
IDK about anybody here, but I run the Champs in the ol'MoPars without issue. I'll leave'em in there for 3 years without thought. On a stock engine or mostly stock engine, unless you up the anti on performance and compresion, the stock plug heat range will do great for a lot of modifcations.

Once you up the comp. ratio and add a cam and so on, theres a possible change in heat range worthy of looking into. Otherwise, a stock plug will do.
 
I figured id pull some plugs just to see how bad they needed changed...man I guess I saved a few bucks they looked almost perfect and nothing fouled out burnt up...had that nice lightish brown/cream color to them..hard to describe but not too lean, not too rich...REALLY surprised me to be honest. The ones in it were NGK's.
 
Im put so little miles on mine the last 3 years ebcause id lost interest the guy at the shop that does my inspections laughed at me..he said...you realize in the last 3 years you have put LESS than 100 miles on your car...and right before I "lost interest" I had done a "tune up"...It had just been so long id forgotten what the plug #'s were and id seen so much about other plugs I figured id ask for some numbers. Thanks all...you guys are making this much easier. I will have a lot more questions about SB's coming up.
 
abodyjoe said:
look through that thread. its down the page some. i would have edited the first post and put all of them in there but for some reason this damn site only allows so much time to edit things.
Click to expand...

Thanks for your help.

Kenny
 
66340SEDAN said:
I run NGK plugs in both of my 340 engines, forget the number but I can check.
Click to expand...
What NGK number are you running? I have a stock LA 360 with a Purple Shaft .484 cam. 4200 stall, 3.55 gears 750 vac. secondary Holley, Air Gap and it runs 7.5's in the 1/8th. with Autolite 65's now. What NGK do you think will work? I have ran a 440 up until now.
 
Mo-Par said:
Autolite 65s ,I have never run anything more reliable ever.
Click to expand...

I put autolite's in my 85 318 and they didn't last 3 months. They were possibly defective, but I'll never know for sure. That's when someone suggested the NGK's and they were in the truck 8mo and were still good when I sold it
 
I stopped using champions years ago when my car ran like crap all the time till I swapped them out. Hate champions. I run standard autolites and they work great.
 
1970 La said:
for me i have had good luck with champions or the GR4 NGK stock #2635
Click to expand...

bingo! NGK V-powers, helps direct the spark to the edge of the center electrode, promoting a better flame kernel. I switched from champions to GR4's in my smallblock, made a very noticeable difference in start up, idle quality, and throttle response. im very pleased.
 
You must log in or register to reply here.
-

Back
Top