What plug's does everyone run?
 

I know it's usually personal preference but what plug's are you guy's running?

I have a 1987 33ft Fountain with Twin 420's that have been beefed up by the prior owner??? AC R44TS were in it when we got it, but what should we be running? If I still have the boat next winter I plan to pull the motor's and either have them upgraded or have them dynoed to see exactly what they are.
We replaced them right after we got the boat last summer with the same R44TS but shouldn't we be running a Marine plug? Keep in mind we are here in Kansas and never run in salt water, but should we still run a marine plug? Wouldn't that be a MR44TS?

Also the back of the transom usually has a black film on it, so should we be running a hotter plug? OR adjust the carb.? I know that rich is safe and lean is mean, but only for a short time!

I would reccommend that you run marine plugs. MR44TS or MR43Ts will do fine.

Been running the AC MR43T plugs for years without any plug related problems. Seem to last quite a while too. Tried the Bosch Platinum's a while back. No improvement in performance, fuel consumption, etc.... they just cost more.

I just go down to the local flea market and buy a sack full for $4.00 and what fits, I use and what don't fit, I take back the next week and sell them back. It runs smooth most of the time...can't beat that $4.00 tune-up

Anyone using NGKs? Alot of people use them in my area.

When changing plugs last spring I decided to go with NGK's on a stock 330. Everyone said they are equivilant to the AC plugs, so I went with em and no probloms.

Had good results with Rapid Fire #1's. Was fouling out MR43's after long idle periods and no problems with Rapid Fire's.

I run NGK BR6FS and I am pleased with them.

I had used AC MR43T`s for years but the center electrode`s sometimes blow right out under hard running. And It`s has happened to a couple of friends also.

I've been running the Bosch platinums in the cars for years and swear by them. I base my plug replacement off the quality of the idle. When I feel the engine start to miss at idle, I'll replace the plug. I was doing this every 15,000 miles with a regular resistor plug. With the platinums, I have never changed one of them, even after 80,000 miles.

I also use them in the boat. But I've never owned a boat long enough to wear the plug out. :rolleyes:

I just installed NGK's last night
What a whore to get between the 2 engines but hell, worth the torn up forearms!!!
the one engine had champion plugs in it, all 8 were fouled out
Second engine had the v groove NGK's in it
Yanked all out and replaced with NGK, Run them in the trans am, in the f350, in the boat and in the LAWN BOY!!!
Only choice for me out there is NGK
Jason
(side note, Trans am Came from GM with their platinum plugs
well these are little mini blips of platinum dropped on the ends. 6 of the 8 plugs I yanked from the trans am had the tips missing, I would never go platinum again after that incident, dont want any piece of metal floating around in the cylinder, if it get stuck to a ring or what not, your going to score up the cyl walls and have problems)
Jason

Bigggus and everyone else is the NGK BR6FS the equlivant of the AC MR43TS?

I might try the NGK next time! I just ordered the MR43TS 5 Min. ago.

Is the 43 a hotter plug than the 44? Will it help the black flim on the transom?

Thanks Guy's!!

You might know, there always has to be one oddball in the crowd so I'll fess up to it! I have Champion RV15YC4 in my 7.4 300 hp stock engine. Ya, I know, I'm a weenie compared to the hp you guys have!:p

Recommended in my boat (454-330 HP) was champion RV8C

why champion as a recommendation on the turtle???
Was champion the best of the best a few years ago?
jason

I just called O'Reilly's Auto Parts and at first they said that they (MR43TS) were a Special Order Item and that they would call me back to let me know when they could have them by......Then they said they can't get them!???! What's up with that?

Where can I get 16 of them? Do I have to go to a Marina for them?

Should I just try and get the R43TS instead? Will O'Reilly's be able to get them?






:confused:

AC Delco help line just said that there is no such plug MR43TS is what I need the MR43T?? Now I confused!

OK I think I got it now!! I just ordered them through O'Reilly's (MR43T) and they should have them by 5pm this evening!!!

Also try the CR plugs from AC NAPA should keep them in stock....They are commercial.....Beefier just like the MRs.

I run AC Rapid Fire #1's in my 92 350 Magnum. Cleaner at idle and since they're projected tip plugs, they run cooler at power. We've run them in a number of modified motors too.

Pick any brand though as long as they are projected tips.

My 2 cents.

Scott

A/C Rapid Fire # 1,,,,, they are worth the extra money.... and I'm sorry,,, you couldn't GIVE me a set of Champions

Funhome, yes, the BR6FS crosses to a MR43T.:)

Champion 802 V63C. Recomended by my machinist so I use them.

Rapidfire #1, Smooth idle no problems:D

We just got done replacing my A/C R44TS with MR43T and all of them were very black (Rich?) But then on the second motor the #5 and #7 had burned the electrode completely away!! It even started to burn the ground away!?!?!???

What does that mean? We asked a area Race car guy and he said it usually means that you are burning water and way to hot!?? Then one of you guy's said that you had the same thing happen to you after a long run!! What do you guy's think?

Funhome, I was burning water on two cylinders before a rebuild. My plugs were clean. They were getting steam cleaned. You may be having detonation if the plug ground and tip are burned away. Change your plugs and try a higher octane to control the detonation.

Funhome,

I would check to make sure that the # 5+7 wires are in good shape and totaly seperated from each other. How does your cap look? You might be detonating. Just a guess :)

Many of you seem to like the Rapid Fire #1. Is this plug ok to use with a 1998 502 MPI?

Thanks,

Padraig,,,, Yes you can,,, I am running them in a 97 502 MPI.

Heres a site that gives some good info on plugs. Also there is a page that has pictures of different conditions of plugs.

http://www.centuryperformance.com/spark.htm

Here is what I know. (or think I do :D )

AC
MR43TS - extended tip marine - No longer available
MR43T - non-extended tip marine - available.
R43T - non-marine (no corrosion resistance)
CR43TS - extended tip non-marine commercial
CR43T - non-extended tip non-marine commercial

Champion
RV15YC4 - extended tip - non-marine (no corrosion resistance)

NGK
BR6FS - corrosion resistant

AC Rapid Fire #1 - corrosion resistant

Thanks Guy's!! This place is the BEST!!:D

You might try the SplitFire with the four electrodes, I had a friend who tried these in his boat and they cleaned up the performance and transom all the way around. The boat ran on the Rev Limiter for the first time since it was new. No more black transom either.

MR43T on the shelf @ NAPA every time I go for them!! Cant figure having to order them:D

NGK UR-5
 

I've run NGK UR-5 "V-Power" sparkplugs in big-block, small-block, and small-block Ford marine engines for years and they seem to work very well.

NGK 5672A-9 or 10's, also Champion PN791.

I just changed plugs. I run AC #1's but the new ones are different than my old ones. Same plug # but different ceramic and electrode???????

SPARK PLUGS
 

I just finished building a pair of 540's for my 35 Sonic. Ihad always ran MR43T's from the NAPA shelf. However after talking with Nickerson's who built my carbs and Tommy at Cheif who i purchased the valve trains from they both insisted on the NGK UR5's stock #2771. They do burn much cleaner and do not load up at idle. I am running Merc ignition with the HP module. These two guys convinced me.

SPARK PLUGS
 

I just finished building a pair of 540's for my 35 Sonic. I had always ran MR43T's from the NAPA shelf. However after talking with Nickerson's who built my carbs and Tommy at Cheif who I purchased the valve trains from they both insisted on the NGK UR5's stock #2771. They do burn much cleaner and do not load up at idle. I am running Merc ignition with the HP module. These two guys convinced me.

NGK "V-power"
 

Nothing runs like the NGK V powers ! I have used them in everything . Everything that used to load up with other plugs will not with these . Also helps on motors that are old and burn oil .Keeps the plugs clean .

Don't use split fires on high energy ignition like an MSD box . It is too much power for the plug .It wil burn tips right off . They even tel you that in the paper work . I here they work good with stock ignition though .

I haven't used the NGK V-Power but I do really like the AC Rapid Fire #1

the TS has a longer tip than the T ....the TS gets the tip farther in the cylinder and more centered. the TS's burn alittle cleaner (less transom soot) in my 365hp.

the M stands for marine and they are corrosion resistant. i change my plugs every couple of years so I just get the R43TS because they are cheaper.;)