Which spark plug??

[Legendary]

I'm about to do a tune up today and I have 93 cobra heads on my stang. I wanted to get the motorcraft spark plugs from autozone but I don't know if I should ask for a 1990 mustang or a 93 cobra. Would it make a difference? What oil would you guys recommmend for a high mileage motor?

Thanks!

 

[HO93LX302]

tell them its a 93 mustang cobra.. I believe the motorcraft # for the cobra heads are ASF32C.. The heads on the cobra motor are different so it needs different plugs then a reg. 5.0 motor.. I just use castrol syntec on my motor has 90k on it

 

[Legendary]

Thanks. Should I gap them different or the usual .054 is good? I do have an MSD ingnition and accel coil. don't know if that'll change anything.

 

[Stang6911]

I would recomend some different plugs, After years of trying out different plugs I am a firm believer in NGK plugs. They are awesome. My second choice would be the good 'ol Autolite's. I have had good luck with both these plugs. The gap you are talking about sounds fine. And for the oil, Try out Pennzoil's High Mileage Oil. Real good stuff for vehicles with high miles. I run it in my Trans Am and it has over 110,000 miles on it and it did wonders!

 

[HO93LX302]

I agree with the NGK's.. I wish I could have found a set for my car.. I would gap them at like .045.. even with the msd .054 could still be to much of a gap and there could be a chance of the spark to blow out

 

[Legendary]

Where can I find the NGK's? I never heard of them.

 

[cardudeusa]

We sell them at Advance Auto, $1.69 a piece, Autolight 25's $1.24 a pop.

 

[85_SS_302_Coupe]

So if i'm buying NGK, that's what i ask for or are you abriviating something? I'm due for a tune up but i'm open to suggestions. I was either getting Motorcrafts or Autolites but if you guys think the NGKs are that good i'll give'em a shot

 

[HISSIN50]

im curious why he would need to close the plug gap. i would think the aftermarket ignition would allow him to open the gap up even a little over stock.
Justin, i can see why you would gap them closer for the blower, but for NA (unless Legendary has a blower, etc and i missed it).
i like M1 for oil. just me.

 

[StreetStang37]

Stock on a 93 5.0 is .052 so I would think .054 should be fine with an MSD.

 

[cardudeusa]

So if i'm buying NGK, that's what i ask for or are you abriviating something? I'm due for a tune up but i'm open to suggestions. I was either getting Motorcrafts or Autolites but if you guys think the NGKs are that good i'll give'em a shot

Yep just ask for NGK's they will know what ya want.

 

[HO93LX302]

im curious why he would need to close the plug gap. i would think the aftermarket ignition would allow him to open the gap up even a little over stock.
Justin, i can see why you would gap them closer for the blower, but for NA (unless Legendary has a blower, etc and i missed it).
i like M1 for oil. just me.

Well I agree with having aftermarket ignition that it probably wouldn't blow out the spark at all but there is always still a chance.. I mean if I was in his position I would gap them smaller but thats just me.. Andrew at LaRocca's told me to gap my plugs at.028.. didn't do them actually only cuz I had a new set that had to go in but I took the blower off

 

[HISSIN50]

as said, smaller gap with boost is very important and i understand.

on NA applications, the gap generally depends upon the strength of the ignition. i know many folks whom run a fatter gap (than stock) with aftermarket ignitions, but never heard someone recommend a smaller gap with aftermarket stuff. people often run a smaller gap if they have a weak ignition and the spark cant bridge the gap.

i would think that a gap of one half of what is recommended (what LaRoccas said) would be for forced induction or something other than NA. i would not run a NA car with that gap, and that was what i was asking for clarification on (thought i was missing something). sounds like aftermarket ignitions are weaker than stock pieces.

 

[87gtconv]

I agree I gap my stock system at .054" and they work fine for years or about 15,000 miles as I dont put many miles on my stang about 117,000 since 87!!! I use Motorcraft ASF 42 A stands for 14mm thread S stands for supression type F stands for Tappered Seal Seat 4 stands for the heat range and 2 stands for projected electrode type!