Autolite Plugs: APP3924 Double Plat & Plat Pro

[Mr95Gl]

Long story short, I ORDERED double plats, and was sent 4 double plats, and 2 plat pro's in another box. Will the two work in conjunction with each other? Not sure if AZ carries them, or I'd just pick up the remaining two. I'd much rather pick them up, then have to deal with another shipping extravaganza I just dealt with. Thanks!

 

[SHOZ123]

Use the single plats on the firewall bank (cyl 1,2 &3) as these are + voltage firing. The front bank by the radiator (cyl 4,5 & 6) are the ones that need the double plats as they are - voltage firing.

 

[SHORANGERBIRD]

-this has prolly been stated 10,000 times, and im sure you prolly know it, but imo MOST of the time putting any plug but motorcrafts you are not only asking for problems, but will prolly have to replace them again before you would motorcrafts. often duplictated, never right......

 

[shobote]

-this has prolly been stated 10,000 times, and im sure you prolly know it, but imo MOST of the time putting any plug but motorcrafts you are not only asking for problems, but will prolly have to replace them again before you would motorcrafts. often duplictated, never right......

Heresay...Unless you have tried other plugs yourself, it does not make sense to tell someone they don''t work. I have used Splitfires and AC DElco Rapidfires (my favorite) and both exhibit smoother idle and better throttle response than the Motorcrafts on my SHO; BTW, I did a direct comparison with new Motocrafts and new Rapidfires one day since I was bored....I kept the Rapidfires in and have been running the same set for 4 years with no problems whatsoever.

 

[SHOZ123]

I'm likein' the new Autolight XPs

 

[SASHO91]

I just put in some Champion Copper Plus'
they fit better than the old NGK V-power did, and preform the same, if not better.

So what if i have to change them sooner. Its only $10.17 for the set.

 

[SHOZ123]

I was running the Autolite Coppers before the Iridiums. 15k and they looked great. Platinum plugs are for those that don't want to change the plugs. I change them once a year or at least take them out and look them over then so 100k life is not what I want.

 

[wood_e]

I ran Autolite double plats in my SHO and didn't have any problems.

 

[SHORANGERBIRD]

Heresay...Unless you have tried other plugs yourself, it does not make sense to tell someone they don''t work.

-you dont have to use them to see problems. many which have been detailed in print and web sites...:type:

 

[sdpatt]

The Motorcraft AGSP32PP was the ONLY plug designed for the SHO engines. These plugs were manufactured for Motorcraft by Nippon Denso. The Autolite APP3924 plugs have the correct double platinum electrodes, heat range and threads, but are 1/32" too tall to let the plug boot seal at the valve cover surface. This will eventually allow foreign debris into the plug wells. If the plug well seals leak, and eventually they will, that grit will make a very difficult to clean soup that can score the cylinders if allowed to enter through an open spark plug hole.

I am using the Autolites now, but have added an O-ring under the boot seal to attempt to minimize the entry of road grit in to the plug wells. Can anyone tell me if the new fine wire Motorcraft plugs have the correct insulator height to allow the design fit of the plug boots at the valve covers?

 

[N3FOL]

Spark Plugs

I am planning on replacing my plugs soon as well. I have about 159K+ and I was thinking of putting in BOSCH platinum plugs that does not need to be gapped. Am I asking for trouble or not?

 

[Racer X]

-this has prolly been stated 10,000 times, and im sure you prolly know it, but imo MOST of the time putting any plug but motorcrafts you are not only asking for problems, but will prolly have to replace them again before you would motorcrafts. often duplictated, never right......

So who's gonna let him know that Motorcraft no longer makes the double platinum plugs for the SHO? :corn:

FWIW, I've tried the Motorcraft fine wire replacement they spec'd... they sucked. I'm using the AutoLite's and couldn't be happier.

 

[sdpatt]

I am planning on replacing my plugs soon as well. I have about 159K+ and I was thinking of putting in BOSCH platinum plugs that does not need to be gapped. Am I asking for trouble or not?

Trouble? Yes.

 

[NWGRN94MTX]

The Motorcraft AGSP32PP was the ONLY plug designed for the SHO engines. These plugs were manufactured for Motorcraft by Nippon Denso. The Autolite APP3924 plugs have the correct double platinum electrodes, heat range and threads, but are 1/32" too tall to let the plug boot seal at the valve cover surface. This will eventually allow foreign debris into the plug wells. If the plug well seals leak, and eventually they will, that grit will make a very difficult to clean soup that can score the cylinders if allowed to enter through an open spark plug hole.

I am using the Autolites now, but have added an O-ring under the boot seal to attempt to minimize the entry of road grit in to the plug wells. Can anyone tell me if the new fine wire Motorcraft plugs have the correct insulator height to allow the design fit of the plug boots at the valve covers?

Scott, try these - Denso p/n PK16R11

 

[N3FOL]

Spark Plugs

Trouble? Yes.

Thanks sdpatt. I am satisfied. I will stick with Motorcraft.

 

[SHORANGERBIRD]

So who's gonna let him know that Motorcraft no longer makes the double platinum plugs for the SHO? :corn::

sorry sir, i dont know where you recieve your info from, but that is totally 180 degrees from correct. the number has been changed, yes but double plat plugs they are. flat bottom with gskt. AGSP32FM. you should check into it....:corn:

 

[Bob Gervais]

I am running the Autolites with Delco wires, and don't have a problem with the plug boot sealing. I am, however, getting a slight misfire recenctly. I've had these plugs in for about a year, and the intake needs to come off soon for cleaning, so I think I'm going to try the Rapidfires. I put them in a friend's ATX SHO (Jamal, you remember Jeff, right?), and it ran nice and smooth with them. Still is, as far as I know, and he's put about 5k miles on them.

As far as Bosch platinums, I've had trouble with them in every car I've ever tried them in. My old 97 SLO, 89 SHO, 87 Suburban, and a friend's Caravan. Methinks that's enough evidence to call them garbage.

 

[SHO Continental]

I'm running the double plat autolites in my '93 and '95. They work just fine. About 4500 on the ones in the '93 and 1500 on the ones in the '95.

 

[shomesomesho]

the number has been changed, yes but double plat plugs they are. flat bottom with gskt. AGSP32FM. you should check into it....:corn:

I was under the impression the AGSP32FM had finewire platinum-nickel centerwire electrode with nickel plated shell, and they are not actually double-platinum plugs.

 

[SHORANGERBIRD]

I was under the impression the AGSP32FM had finewire platinum-nickel centerwire electrode with nickel plated shell, and they are not actually double-platinum plugs.

yes, that is correct, but then the original PP plugs were nickel electrodes....
its all of a ford thing to consolidate the many sparkplug numbers they have, so that its cheaper for them and the dealers to cover more vehicles with less product stocking. hence the "one size fits all" covering. they are though still a "specialty" plug with very few uses other than the SHO, and are of propriatary design for fit and performance in SHOs....:type: