I found all kinds of threads in the FAQs/How-Tos on how to change the plugs. What I want to know is do I go 1 step Hotter or 1 step colder for better NA performance......

Hotter...as long as you don't induce detonation, which will cause the ECU to retard timing.

how much HP would you get by going 1 step hotter NA

would it even be noticable

make sure there NGKs

Hotter is a bad idea. You will lose power, as the ecu will retard the ignition.

You might gain a little from going one step colder, as it will run a little cooler, allowing for a little more advance, but the plugs will also tend to foul out in about half the time.

Remember its about heat range. Hotter is not better in terms of making power, when going above the stock parameters.

How about just staying with stock?
It's worked well so far, right?

Well I would like to get some that will give me a little better performance. My stock y-pipe, exhaust and intake worked fine too but I changed them out ......

If I did go 1 step colder would that hinder performance or do nothing at all?

And yes im going to get NGK.....

If you're gonna do ANYTHING, you might as well go 1 step colder to possibly prevent pinging. Otherwise, stay stock.

Hell, while you're at it, you might as well hack your ECU and advance the ignition timing all the way to its limit, raise the compression ratio to 14:1, port & polish your intake/exhaust ports, etc...
Point is, changing spark plug heat range usually isn't something you do unless you REALLY have a GOOD reason for it

I thought most people on here changed their plugs out (including changing heat ranges) and not just the Nitrous guys. I figured since they need to be changed, now would be a good time to do it.

The only max that Ive run into w/ different heat range plugs was SamMan32 who had 1 step hotter. His car shot off the line ALOT quicker than mine and I think all he had was a y-pipe.

I see... interesting.
I'm changing my plugs soon, but using coppers with the same heat range as the originals...

WRONG....you will LOSE power with 1-step colder plugs, there have been dynos here/mags/elsewhere proving it. However, we are talking about 3-6whp gained or lost *MAYBE*, so it's not noticeable except on a dyno.

Running one step hotter plugs won't induce detonation as long as you're running QUALITY(Chevron for sure) 91+ octane fuel UNLESS it's extremely hot outside and the car is under heavy load, ie loaded going uphill with A/C on or lugging the engine in too tall a gear from a stop.

Considering it's winter, as long as your car is in a proper state of tune, you *WILL* gain power although minimal. Running hotter plugs on higher mileage engines with carbon deposits during summer temps will cause mild->medium detonation on SOME cars.

Personally, I'd run Iridiums with STOCK heat range year round vs. regular hotter plugs.

I suggest people who want information about plugs visit NGK's website. The heat range on the plug has nothing to do with the temperature of the combustion inside the cylinder, rather it deals with how much heat the plug can dissipate from the cylinder. Remember plugs serve two functions. 1) Provide the spark for ignition 2) Dissipate heat

Now what some of you may be thinking about is not changing the heat range, but changing the GAP of the plug. By doing that you can alter the charateristics of the spark and that can cause preignition or detonation (which are not the same thing)

Icy Hot is right. Medicsonic's car ran like crap with colder plugs. We were at the track in Maryland and he couldn't break out of 17's. I was running 16's and killing him in the 1/4.

Ohannon just go with copper instead of platinum.

Well, I just switched to NGK cold plugs and lets just say the dyno leaves something to be desired. My dyno is on my homepage. Some people have suggested some possible reasons for the slightly low power. One suspect is the cold plugs.

Colder plugs run bad in NA? But wouldn't coppers be colder plugs?

Copper is just the type of plug, it doesn't mean they are colder.

S

Copper plugs aren't necessarily colder, but the copper firing tip runs a little cooler I believe... or rather, platinum firing tips maintain a higher temperature (which is good for longevity since it helps keep the firing tip cleaner, but it can in theory promote pinging moreso than copper)

broaner22, what do you mean? Did you gain or lose power w/ the colder plugs?
I do plan on getting Coppers....

I don't know if I lost power for sure, but don't you think my dyno should be a little stronger with the mods I have. Let me get this straight colder plugs are called cold because they are meant for cold climate and have a hotter spark. Is that right? Well I got NGK cold plugs from the dealer and it doesn't seem to have made a difference.

No. Coppers will run more voltage than Platinum plugs because copper has less resistance.

No colder plugs are called cold because they remove more heat from the combustion chamber than stock plugs...the spark is just as hot...