Actually, yes it probably did work for you if you changed out stock plugs from 50k miles.

they will last maybe 20k miles and be worthless, copper was meant for our magnums not platinum and i have personally used the +4 Bosch and they where horrible. the 4 prongs on the plug actually hold back the spark and it decreases the effectiveness of burning the gas. You gain 2-3mpg is a total lie. Otherwise everyone would be doing this right now. Let me guess your r/t gets what 18mpg now? LOL doubt it BIG TIME. 2-3mpg is like 30+ a tank i have tons of mods on my truck, that are suppost to increases mpg and i have yet to see anything over 300mpt with any of it, and it all claims to add 2-10mpg LOL!

MSD Ignition, with 3923s, Intake, Exhaust, intake manifold and 1.7 and a mopar pcm running on 93 octane, and my mpg has increase by maybe little over 2mpg... my best tank so far was 260 and that was running it after the gas light came on so about 230 till the gas light, when i first got the truck it was getting about 195 to gas light, 125 if i ran it further, and i have to be gental with it also to get them numbers.. if im on it.. im close to 11-12mpg if i baby it i get about 13-14 maybe 15 if im lucky and the whole universe is on my side. -_- lol.

Did you re-gap your +4s? Or take them right out of the box and install them, did you replace the rotor, wires, cap, and coil? or just plugs?

spark plugs alone will not give you a 3mpg gain...

im telling you right now, if your truck got 2-3mpg increase off just plugs then prove it and you will be worshiped, try doing this as evidence.

Install your stock plugs or w/e you replaced back in. Reset PCM, and turn it over about 3 times to fully learn plugs installed, go to the gas station fill the truck up normal octane unless you use 93 like me.

Reset milage, drive 20 miles total back to the gas station, fill it back up, take numbers on the amount on gallons it takes exact numbers.

Go home replace the plugs, do the same thing as above after resetting pcm, and do it again.

This will prove your 2-3mpg increase and then ill go out and buy a set of these for SURE!

also 50$ for plugs is sick.... i paid less then 10$ for my 3923s..

 

user's right, 2-3 mpg increase with just spark plugs is ridiculous unless your truck really just needed a tune up. trust me, i ran the platinum2's for a while, after about 6 months the truck ran like ****. not to mention those stupid prongs can break off, when then get embedded into your combustion chamber or cylinder head, they're garbage.

 

The reason the 3923 doesn't show up in auto shop databases is because it's not a factory plug style for the 5.2L/5.9L motors. The 3923 is a little bit shorter and one heat range colder than factory plugs, but they have the same thread pitch so they can be bolted in without any fitment problems.

The main benefit of using a colder plug is to reduce detonation, which tends to be a common problem with the OEM 5.2L/5.9L motors. Technically the 3923 is not making more horsepower than the 5224 - you're just hoping to recover some of the horsepower that may have been lost due to detonation with the hotter plug. If you're not detonating with a 5224, it's possible that you may not see any power gains when switching to a 3923.

 

Installed the 3923's. Seem to work alittle better than old plugs (better idle, maybe smoother acceleration). Thanks for all the advice. Just wanted to install a plug that has been used by others with good results. The most amazing part of the plug was I think I dropped a whole second off 1/4 mile, yet gained 8mpg. I think by just installing the plugs I must have gained 35-40hp. I think Metalsrfr just might be one to something.

 

OK user I dont doubt you here but there is no way in hell I will ever get 18 Mpg's out of this truck try between 12-14 before I put the +4's in I was getting 10 Mpg's in town and on my whole drive from Texas to Virginia I got 12 Mpgs interstate (ouch my pocket is starting to hurt thinking about that drive again)now it could have been that my truck needed a tune up being that I bought it about 2 weeks before I drove it to VA and didnt really have time to work on it except to get the brakes fixed.But I have only been running them for about 850 miles now . No I did not replace the rotor, wires,cap , or coil just the plugs and no I did not gap them . I run mid grade in my truck after a few tanks of each octane my truck responds better to midgrade, and I get between 230- 245 depending on when I fill up I try not to let my gauge go below a 1/4 tank. but I will go and buy a set of 3923's and do the test that you suggest this weekend , Im not trying to prove you wrong or make you look like an a$$ I was just stating from my experience !
and If I am wrong and I do get better Mpg's and response its not the first time Ive been wrong ,And just so you know ICE systems (Internal Combustion Engines ) are not my specialty Ive worked with Turbine engines in the M1Abrams main battle tank for the last 8 years and now im going to school to work on the Turbine engines in helicopters , This is my first V8 that im getting into modding and racing, I previously owned a 85 Toyota Celica Supra that I rallied . So once again I was just stating my experience from using the platinum +4's.

 

... i think we need a sticky on top of the 2nd gen page about spark plugs. theres at least one thread a week full of arguments over spark plugs. moderators, you know what to do.

 

I said with the stock plugs you took out, you said you gained 2-3mpg after installing the new plugs. Dont test it with new plugs put your old ones back in not the 3923s

Also what was wrong with your brakes? Was any of them rubbing or grinding or anything to cause drag? Replacing the brakes can free up drag and increase mpg you know? lol. Also did you feel your tires up with air? that increases mpg also, most people do this on long trips.

and you said 10mpg to 12mpg on the trip. Thats 2mpg not 3mpg. LOL, just messing with you dude. Also highway driving you see better millage, but im sure you know all this you seem like a smart dude, if you work on turbine engines and going to school to become an expert.




i look here every week or every day, and i think this is the first in a couple of weeks. Yo! hehe.

Also i have a link at the top its called tips and tricks it tells you what type of Spark Plugs to use.

Even if i did sticky everything up there, people would still ask, i even sticked a calculater for tire sizes and gear ratio and ~dyno, people don't use it. I still see people asking about tire sizes every day.. lol.

 

i enjoy my 3923 plugs from wally mart, one of the cheapest investments out there. i had the 5224 from autolite and lost about 50 miles to a tank of gas. yep they were the plats. went to the 3923 and all problems went away. no more stumbling at lights or stop signs. smoother running. and really good with my 125 shot of nitrous. might switch to the 3922 to see if it runs better on the bottle

 

I had to replace the brakes a week after I bought the truck the front brakes locked up on me and wouldnt release,come to find out the rotors were severly warped and the drums were shot so those got replaced before the trip and I also replaced the tires before the trip cause the nitto's that were on there were horrid I would slide down the road when it was dry out and I didnt want to risk it with driving to VA that was all I did before I left on my trip after the trip up here I changed the plugs, I got exactly 12 MPGs the whole trip after changingthe plugs I started getting 14 MPG's. A few weeks after that I changed the T-stat to the 180 I got that from youre tips and tricks post and I love the way it runs when it stays cooler.So I do not have the original plugs that I changed from I threw them away . Ohh yeah and by the way Turbine engines are so much easier than an ICE engine .

 

Where did you get your Billet Fuel Rail? Im looking to replace mine, along with the injectors soon.