Which Spark Plugs are best??

[HISSIN50]

Ok, here's what I got from Airflowresearch.com. They recommend the "Autolite 3924" for their Heads. As was mentioned earlier, thanks! Now this leads to another question....

I've seen a lot of "Platinum" bashing this thread... but I've also seen this Autolite "Platinum" plug suggested a few times. Sooo.......... ??

i agree with "IDB" Mike, et al. (sorry Mike, could not resist.)

platinum sucks. it is very hard and as a result, does not conduct well compared to copper. think of cheap, really hard rubber tires vs some nice soft Nittos. the hard rubber ones will last forever, but which do you want to autocross in?

platinums are nice for some applications, like Z28's. i lost much skin and hours doing plugs on the 94 camaro, though i did use copper, i can see the need for platinums. it is funny that people remarked that the bosch platinums broke. i found a huge miss in the eclipse last week. came to find that one plug had separated from the body (if i turned the ceramic part, the electrode spun too).
i agree in full with others that while they may be good for 100K in terms of gap erosion, they may break long before that.

on EFI stangs, the side effects of platinums seems to be a low idle and cutting out at or above 4K rpm.

i did not know Autolite made platinum. arent coppers good for 30K (maintenace interval from ford)? i dont leave plugs in for 1/3 that long anyhow. gap them a little tight to help with accomodating gap erosion in they are going to be left in for awhile. also helps with weak ignition.

just my two cents worth.

PS, Mike, i was reading timing chain threads last night. came across one of yours from the Corral a few years ago (when the bolt in the block stripped, etc). how was your chain when you eventually got to it? you did not have a lot of miles on it, as i recall. curious, i have a thread about life of chains going.

 

[5.0CRAZY]

I used motorcraft, but I dont how people call them "cheap stocker" parts. When I went to the ford dealership they wanted about $108 for cap/rotor/plugs (no wires)! About $5.50 a plug too I think. Thats Canadian money but still about 70-75 bucks US.

 

[TOM B]

Edelbrock recommends --------- Champion,,, no really, they do.
they probably own stock in them,

 

[thompsonsd]

Well, after a review of all the inputs I think I'll go with some motorcrafts. I can't have my spark dying off after 4000 rpm now can I! I think I'll put the Platinums in my Explorer though, that never sees very much rpm anyway.

 

[TheUser]

go to wal-mart and get motorcraft if that's what you want...they're like 2 bucks each

 

[red94fiveo]

Autolite 3924's are $1.27 at O'Reillys. Autozone doesn't stock them for some reason. And yeah, what eveyone else said, Autolite's are the best.

 

[Mustang5L5]

PS, Mike, i was reading timing chain threads last night. came across one of yours from the Corral a few years ago (when the bolt in the block stripped, etc). how was your chain when you eventually got to it? you did not have a lot of miles on it, as i recall. curious, i have a thread about life of chains going.

Ah, i remember that thread. I never posted what happened.

I ended up getting a little 6" pipe wrech on the snapped stud barely and did get it out. At the time i did not have access to air tools and could not take the balancer out to do the chain. I got lucky though that i got the snapped bolt out.

As i was putting it all back together, i took the opportunity to take the radiator out and mount my Sn95 a better way. Well i slipped and drilled a hole into my radiator. I was pissed. Ended up having to go buy a Pep boys 3-core radiator.

3 Days later, i finally finished the water pump install from hell.

My original timing chain is still in there with 103K miles. I'm not too worried about it. But first weekend after i finally buy myself a new Mustang the motor is coming out of the '88 for a refreshing. She has some small oil leaks that i want to address plus i want to paint my block and the engine bay and all that.

 

[Starscream88]

I use Motorcrafts, Work fine, and are a dam good plug,

I try ot stay as much Ford as I can, after all they designed the car, they made it, who am I to say there parts are crap

 

[87gtconv]

I know their temp guage is crap!!

 

[GrandmasterK]

I had Bosche Platinum's in my car when I bought it... misfires all the time. I got Bosche Platinum 4's a few summers ago and it missfires less, but still does (I have to run Premium gas too or it missfires horribly)... I'm be trying out copper ones when I take the Stang out of winter storage, I hope it's a big differance, I'll let you all know in a few monthes.

 

[HISSIN50]

Ah, i remember that thread. I never posted what happened.

I ended up getting a little 6" pipe wrech on the snapped stud barely and did get it out. At the time i did not have access to air tools and could not take the balancer out to do the chain. I got lucky though that i got the snapped bolt out.

As i was putting it all back together, i took the opportunity to take the radiator out and mount my Sn95 a better way. Well i slipped and drilled a hole into my radiator. I was pissed. Ended up having to go buy a Pep boys 3-core radiator.

3 Days later, i finally finished the water pump install from hell.

My original timing chain is still in there with 103K miles. I'm not too worried about it. But first weekend after i finally buy myself a new Mustang the motor is coming out of the '88 for a refreshing. She has some small oil leaks that i want to address plus i want to paint my block and the engine bay and all that.

Mike, thanks for the info/conclusion. glad you got the bolt remains out and did not have to jump through as many hoops as you could have, to get it done. i know you cant stand to leave anything alone, so the motor coming out does not surprise me one bit. LOL.
thanks for the info. i appreciate it.

 

[Lxpony]

on my gt40p heads I will be running the stock plug for that head which is a motorcraft platiumum plug...

 

[PuppyDawg]

Autolite 3924's are $1.27 at O'Reillys. Autozone doesn't stock them for some reason. And yeah, what eveyone else said, Autolite's are the best.

Autolite 3924's? or the Autolite AR3924's????

 

[89lxvert34]

i like splitfire

 

[Mustang5L5]

on my gt40p heads I will be running the stock plug for that head which is a motorcraft platiumum plug...

The stock plug for that head is if it was on an Explorer. The ignition is not the same as a Mustang and is designed to use that plug.

For Gt-40P's on a Mustang, you use the same plug as the Gt-40's, which calls for a copper plug. (Autolite 764 or Motorcraft 42C)

 

[Starscream88]

The stock plug for that head is if it was on an Explorer. The ignition is not the same as a Mustang and is designed to use that plug.

For Gt-40P's on a Mustang, you use the same plug as the Gt-40's, which calls for a copper plug. (Autolite 764 or Motorcraft 42C)

Agreed,

No use spending more if you dont need it,

 

[5.0 HOtrain]

I was going to use autolites in my 418, Trickflow recomends 3932's for the "R" heads, couldnt get any in time, went with NGK instead (also listed on trickflow website)???

 

[thompsonsd]

I just installed the Autolite 3924's. First thing I notice is that they thread twice as far into the head as my old plugs!!! I mean that very literally, they really do screw into the heads twice as deep! I almost didn't put them in....

I haven't had a chance to test out the power increase yet (heavy traffic out here right now), but I did start it and let her warm up for a bit. Two things were very noticable:

1) I actually had a much smoother idle.

2) My idle was about 350 rpm higher...

Wow, didn't expect all that. I'm sure it's going to feel nicer going out for a drive later tonight!

Anyway, thanks to all of you who took the time to send your inputs! I also hope this proved informative to many others with the same questions.

 

[PuppyDawg]

I just installed the Autolite 3924's. First thing I notice is that they thread twice as far into the head as my old plugs!!! I mean that very literally, they really do screw into the heads twice as deep! I almost didn't put them in....

I haven't had a chance to test out the power increase yet (heavy traffic out here right now), but I did start it and let her warm up for a bit. Two things were very noticable:

1) I actually had a much smoother idle.

2) My idle was about 350 rpm higher...

Wow, didn't expect all that. I'm sure it's going to feel nicer going out for a drive later tonight!

Anyway, thanks to all of you who took the time to send your inputs! I also hope this proved informative to many others with the same questions.

please inform me/us on how your drive went that night....and if you noticed a increase in power or anything else you've noticed.....thanks

 

[thompsonsd]

Oh yeh, the drive went very well. I do feel an increase in response and power!