spark plug gap??
 

i have an 88 gt not stock but, i need to know the gap of the plugs before i put new plugs in it.

i didn't gap the last ones b/c i didnt know but i want to do everything right so i must gap them this time
thanks
:)

I believe it's something like .054 inches, which would be 54 thousanths of an inch. I may be wrong.

.054" is the stock gap. Need more info on what exactly "not stock" means.

i say .045, if you have a stock coil, and are n/a

reply to not stock
 

well its not all stock anyway

f cam,65mm tb,underdrives,ported stock upper and lower intake,ported and shaved heads.

yes i know i need to get rid of the stock intake but i dont have the money for a gt 40 intake:(

so should i use the gap of .054 or ???

.054 will be fine.

You didn't mention the ignition in your list of mods. If you shaved the heads, then the compression is slightly higher, which means the gap should be less. With a stock coil, I'd start at .045", but that's just me.

:)

Take care,
~Chris

i love it when someone agrees with me:)

So lets say that a person has a nice msd al6 and a big fat coil to match.... I've read all these claims that opening up the plug gap will make a bigger spark and get better milage and more power and so on. Should I? And if I do, by how much should I open it up?

I have that setup and nitros oxide and i set my gap at .055. i might use .065 n/a but i'd test it befor i depend on it.

Stock compression? Go for it. Compression is a bigger issue than your ignition system when it comes to deciding your best gap, but ignition quality is important. If your running stock compression, and spent the money on ignition "upgrades", then go ahead and take it up to .060", if you want to, but listen for pinging.

the .65 works like a charm! I can feel a little difference in power but a lot of difference in idle and smoothness. Cool

did you put in new plugs when you opened up the gaps?

Nope, actually, these were the same old bosch platinum plugs that have been riding along in the motor for 2 years. If anything, they looked a little whitish from being lean but nothing serious. It worries me that these plugs have a microscopic pin of an electrode. Makes me think that they'll get clogged by some debris but hasnt happened yet. Oh yeah and 1 plug doesnt match the rest. The set is a bunch of r3 131's and plug #5 is an r3 289. I broke one off and noone had these plugs anywhere except autozone and their computers reccomended the 289.