i have played around quite a bit in race cars with plug gaps, what have you guys found to work best on these trucks? can they take a bit more gap? do they like it or is it a waste of time? I am getting ready for the spring tune up!

 

In my humble opinion and experience, its a waste of time - install a quality plug with some anti-seize on the threads and gap it to spec is your best bet. I use Autolite platinum plugs and run them darn near forever.

 

i have always been a fan of the nkg v power plugs. never had any issue with them yet. you can gap them a bit larger if you want. i pretty much started gapping all my plugs to 0.045 like chevy's. no issue with it yet. i don't know if it is really worth investing in platinum plugs. i found they run the same as any other and the gap opens up over time just like others. i would probably never buy them. no real benefit as far as i can tell other than them just costing more money to buy.

 

My truck likes bigger gaps. At least, when I put new ones in gapped at the spec it seems to lose power. So I put em at least .040 or more. The old ones usually end up being about .050.

Oh, and only Champion copper plugs for me, sans long tip. I get the RC12YC which was for the earlier 2nd gens. The stupid long tip RC12LC4 I gave up years ago.

 

I went from semi worn out double platinum autolites previous owners installed to my current average copper ac delco at the stock gap .035 and actually noticed a power improvement, could be since these were newer or these trucks really do run the best with your run of the mil copper spark plugs.

some swear by the 1 step colder than stock autolite 3923's iirc.

I heard those champion copper plugs were good in these trucks too and stock oem too. I guess they discontinued them years ago but searching around online some years ago in forums seemed to love the "champion truck spark plugs" . I found a box searching online and they were literally called Truck spark plugs lol. Dunno if they were different than the regular champions....I remember reading something about the long tips not being so great either. -shrug-

I'm not sure if gap would matter much on a stock engine. I always find reading about what people use interesting, some swear by platinum or even iridium and others say theirs runs like crap on anything but cheap coppers

 

I believe the platinum and iridium take more energy to produce a spark. (They have more resistance). It's not a big deal for vehicles with a coil for each cylinder or a coil for 2 cylinders. Our trucks have one coil for all 8 cylinders, so they have less time to build a good spark. The coil needs time to build the field (coil saturation) and then collapse it, which produces the spark. I think I gapped my plugs at 40. A bigger spark sure won't hurt anything as long as you can make it reliably. I think our truck can do that on copper plugs with good quality cap, rotor, and wires.

 

on a little bit of a side note now that we mention coils, has anybody tried the MSD coil for these trucks and did they help with power any? I'm unsure of the age of my old looking coil and figured a new one surely couldn't hurt. There are some cheap dinky ones for sale online, couldn't find an actual mopar one...at about 40ish bucks new on amazon the MSD seemed like a good deal. I wouldn't wanna go with some unknown one and end up stranded. Some claimed the MSD coil alone made their vehicles run alot better than before.

 

Truck plugs were the bomb. Stupid they discontinued them. I've searched high and low and never found them again. Anywhere.

 

I put a Standard Motor Products coil on mine. UF 97 $25.79 on Rock Auto. MSD has good products, I don't think using their coil would be a mistake.

 

The rare-earth plugs only real advantage is how long they last. Aside from that, they tend to run a bit hotter than coppers. Also tend to be more heat resistant. So, might be able to solve a lot of the 'rare-earth spark plug' issues by getting plugs a step colder than stock. I have a v-10 though, and I am not about to crank out 100 bucks or so for spark plugs....... It's just not economically sound. Sure, they may last three times as long, but, they cost MORE than three times as much...... If you are paying someone to change them, maybe they are worth it, if you are changing them yourself, they are not.

Expanding plug gap a bit likely won't hurt you, provided your coil is strong enough, the most important thing here is, your plugs should all be gapped the same.