Spark Plugs-Heat range

VINCES

Registered User
HEat range question...i read a few of the older threads talking about heat range/boost, etc....not sure what range to use, on a 94, with an early style blower pulley, and raised top....One range colder or stock?
 
If you're running the older style pulley I think you're OD'n the blower by what 5%? In that case it wouldn't hurt to run one range colder...
 
I would go with Autolite 764's they function one range colder than stock, the 103's are 2 ranges colder. I'd also recommend adding an IC fan as the next improvement.
 
According to the other threads...the 764's same heat range and just shorter (ending in 4?)????

Funny you should mention IC fan...just came in mail last friday....and I spoke with my buddy who is a welder about making me some type of bracket, because i don;t want to go through the cooler with the mounting plastic.
 
???

#2 07-29-2003, 11:28 AM
gldiii
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The 22 is the colder plug. How the numbers work is a little different for each plug make.

Here is some info from a table I made up from a lot of spark plug posts from here and on other boards:

Plug............Part #........Heat Range...Comments
Autolite.......APP2544....Stock.............Long end
Motorcraft...AWSF34PP.Stock.............Long end
Autolite.......APP764......Stock.............Short end
Motorcraft...AWSF32PP.Stock.............Short end
Autolite......APP103.......-1..................Short end, 1 range cooler
Motorcraft...AWSF22PP.-1..................Short end, 1 range cooler

These 764 and 103 plugs are a little shorter than stock, but many people (myself include) use them with no issues.

Many people believe the shorter plugs run even cooler than the range suggests (don't stick out into the combustion chamber as far), but I have just listed the actual range on the plugs here.
__________________
 
According to the other threads...the 764's same heat range and just shorter (ending in 4?)????

That is why I said they FUNCTION one range colder, since they aren't actually one range colder than stock. If I remember XR7Dave made a post on what plugs you should run with xxxxxparts, I'll see if I can find it.
 
Thanks. Now I have to figure out how much boost I will have. I haven't switched to the early style oulley yet, still running OEM 94 pulley. My headers, and freer flowing exhaust I would think have cut down on some of my boost. I thought I read that a 5% would give ~1.5 psi of additional boost, so can a ~3% give ~1 psi? In other words, with my exhaust, I would think I wouldn't be at 15psi????
 
really confused now, too many choices. How about 764pp's, and .045 gap???????????? That's considerably less gap than factory setting...
 
use the 764's and gap them at factory setting. Then take it for a drive and see how it feels, if you feel it missing then gap them at .045. Just be carefull gapping with the platinum plugs not to damage the pucks. I dont't use platinum plugs cause I change them every year, and they are only a 1.60 for the regular plugs vs. 4.00 for platinum. You just have to change them more often. Just an FYI I am running the 103's at .030 gap with 18-19 psi and have not any problems.
 
Spark Plugs-Heat range
do a general search online for the above, there's mass info out there on this subject...besides whats said here...what works for me, might not work for you, or the next guy...

my car is using the XP 5144 IRIDIUM's - this time out, i did do a regap to .045, got a killer deal on them - so figured id try them out, the car runs out strong, plug color is where it should be, and i dont have a problem changing them or checking how their burning, which seems to be an issue for some, in general dont over look the ignition system used on the car, this means the whole ignition system, not just a set of plugs, how about plug wires ,are plug wires, A--equal to plug wire B, or is coil A equal to coil b, our the outputs the same, anyway - - depends on the app., of the car, mods, driving style

cheers
 
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Yeah, I guess it would be inpossible to have a matrix for every car, and mod....has to be some trial and error, but of course, it would be easier if everyone else did the tril and error! LOL.

Also, if you have a certain condition, such as mine with lean, certain fixes can lean in one direction or another as a guideline. is there a plug choice for a lean condition?

i plan on cleaning the MAF, and looking at the plugs, hopefully this weekend....maybe i can post a plug picture....i was getting a '10' and '30' for the first and third cylinder...i will make sureto number them on the way out!
 
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