SP542 Thread

[Jeff-Ohio]

so whats the consensus about these spark plugs? Definitely do it?

It didn't do anyting for me, but others appear to have had success. I would say it is worth a shot based on their feedback since it is a fairly cheap test.

 

[zombiekiller]

so whats the consensus about these spark plugs? Definitely do it?

if you want to do something, gap your stock plugs to .030 and be done with it.

while it made a small smoothness improvement, i hardly think it is worth the trouble ( and it takes all of 10 mins to do all 6 plugs).

 

[chujk1985]

if you want to do something, gap your stock plugs to .030 and be done with it.

while it made a small smoothness improvement, i hardly think it is worth the trouble ( and it takes all of 10 mins to do all 6 plugs).

What are the potential negatives of the SP542's? I read some of your issues, but it seemed unrelated to the plugs maybe?

 

[zombiekiller]

What are the potential negatives of the SP542's? I read some of your issues, but it seemed unrelated to the plugs maybe?

If the heat range is too cold, the spark plug will be unable to properly self-clean by burning off carbon deposits.

 

[Gargamel]

I am surprised this new of a vehicle needs such high maintenance with spark plugs already. Aren't the plugs rated at 100k miles from the factory?

 

[zombiekiller]

I am surprised this new of a vehicle needs such high maintenance with spark plugs already. Aren't the plugs rated at 100k miles from the factory?

it doesn't "need" them.

depending on the particular motor, these can sometimes smooth out idle and hesitation.

If you're experiencing any of the following: detonation, pre-ignition, or power loss; colder plugs could alleviate it.


I am surprised that more "gear heads" are not familiar with using different spark plugs to better tune their engine.

in all reality, for every 75-100 HP that is added to a motor, you'll generally want to go one step colder. ( be wary though, not all spark plug MFGs rate their temp ranges the same).

the leaner your AFR is, the colder the plug should be ( in general).

just remember colder heat range = faster heat transfer.

The fact that the tuners are saying that there is no need to change plugs leads me to believe that the AFRs on most tunes are fatter. ( and that they are being cautious with thier tunes.)


If you find that your motor is adding or removing lots of timing (like more than 3 degrees + or - during normal, steady throttle operation) this could perhaps be a solution that Ford certainly isn't going to offer you.

 

[gily25]

I install them yesterday, its very easy as there is lots of space to work, I space them to .027; I installed the Whipple CAI, tune and ADD intercooler, whipple suggest to space stock ones to .025" however they told me that if I have the SP542 it would be better to use them, so far the truck runs ok.

 

[kandewinn]

Ran these for a few hundred miles. There was no magical moment once I added them. Fuel economy did not change. What did happen is My trucks computers did not like them. Truck slowly developed a rough idle, shift strategies seemed to become confused. Swapped back to my 22,000 mile oe plugs and every developing issue immediately went away.

Lesson Learned...If it ain't broke, don't fix it

 

[Gsteve]

Ran these for a few hundred miles. There was no magical moment once I added them. Fuel economy did not change. What did happen is My trucks computers did not like them. Truck slowly developed a rough idle, shift strategies seemed to become confused. Swapped back to my 22,000 mile oe plugs and every developing issue immediately went away.

Lesson Learned...If it ain't broke, don't fix it

odd , thats the first time anyone has reported a problem.

 

[10SpdsOfFury]

I have 8k on my 542’s and it’s still running like a sewing machine.