topspeed

are colder plugs necessary if i'm looking at under 200HP and under 10PSI boost?

robs99si

from what i've heard they're not necesary, but you do have to gap your plugs to .028. i ran 1 step colder plugs for safety. call up ngk and ask them for the stock #.

topspeed

whats the worse that will happen? melt or crack the plugs?

KFB

it's just a good practice to use a step or 2 colder plug when adding boost.
if the plug stays hot then the engine could be more likely to suffer from pre-ignition and/or detonation.
but what do i know b/c i haven't boosted my ride yet

djfob

You can just run stock plugs and gap them down but if you really want colder plugs all you really is 1 step colder.

IndianRide

You can also run copper anti seize to lower the plug temp hard to find but it gets the job done.

sohc_mshue

i would run 1 step colder to be safe.

Boosted_StinkyNuts

6psi-10psi= 1 step colder
11psi-15+psi= 2 step colder

This has always worked for me. Its good and cheap insurance to run cooler plugs. If you dont git new plugs, at least gap da plugs. doesnt hurt do retard da timing a bit also. Keeps the detonation gremlins away. I had a spark plug part number and and conversion thread somewhere on here. Too lazy to look for it though. If you need the Denso 1 step colder Part # LMK. You can pick em up @ Autozone. Hope this helps.

ONECAM

i have heard that you need to gap them tighter. what is the purpose of this? i have mine gapped at .032 i believe,, i know the stock gap is around .04 can anyone explain why you need it closer?

absolutezroo

closer means less of a "spark" length..i'm assuming that means it will run cooler