Hey guys

I'm new here and new to the modular powertrains. I've been playing with a 94 Lightning since 1999, so I know the small block motors inside and out, but the 4.6 and its quarks are new to me.

I bought a 98 Nascar F150 a couple months ago and I've noticed a couple things with her. I installed a new set of plugs about 5000 miles ago (shes got 54k on her now), and also did synthetic in the M5OD and a hurst shifter.

When I bought her, I noticed a little rattle when letting the clutch out from a stop and also sometimes under accelleration. I figured it was just a shield or something rattling around. Since I did the plugs, however, I seem to notice pinging under moderate and hard acceleration. Here's my questions:

1) Is it possible that I put the wrong plugs in? I used a platinum NGK equivilent to what was in the truck (NGK-3403).

2) The Hurst creates a lot more tranny noise then before, so is it possible that all I am hearing is vibrations and noises from the trans under hard acceleration and that is my ping?

3) I put in a magnaflow muffler around the same time as I did the plugs. I know that the Nascar trucks had a tweaked computer because of the exhaust tip used, so is it possible that the flow through muffler is creating a lean condition? If thats the case, what should I do?

Any help on this stuff would be great since I want to take her to the local dragstrip tomorrow for fun and I don't want to hurt her if she is pinging.

Thanks! Mike

 

I have recently bought a nascar f150 as well and i have been having the same issues. Plan on changing the spark plugs but wondering what kind of feedback and recomendations you would have.

 

Pull the NGK's back out and replace them with stock Motorcraft.

 

x2

 

The NGKs you have are the correct plugs for that engine. A ping sounds like ball bearings rattling around in a tin can. If your transmission sounds like that then it is time for an overhaul.

 

NGK makes good plugs. I have them in my truck and there great.

 

I run NGK's in my boosted trucks