Ok, I've seen and heard so many different opinions on what spark plugs to use and what gaps they should be after making modifications. Now let's put all our experienced minds together and clear things up. I want to change out my original plugs and only want to do it once correctly. Through out the years, I've personally gone 1 colder and re-gapped them smaller. With my mods I'm thinking I should go 1 colder and gap them at .034. Occasionally I go out to the track and throw in some 100 octane, so a colder plug should benefit me more I would think. Also, I've heard that silver is the best conductor and the Nology Silver plugs may be the best choice. This forum has people doing different things than others so let's here everyone's input on why they think their way is the correct way. It has gotten so confusing to say the least.

Here's some info on the Nology Silvers for our cars from HPAutowerks....

http://hpashop.com/product.sc?productId=97

 

I have been running the one stage colder Iridium plugs for about a year and a half now...gapped to .035".. this is working very well for me and I mix some 110 race gas (1/1 or 1/2) for the track....

 

Great post for the day - as I just pulled my plugs for inspection after 19K+ miles on the 1 step colder NGKBKR7EIX-11 gapped to .035. I'm very impressed with these plugs and happy with how my car is tuned and running.

I installed these plugs along with the 185MM pulley. I haven't put a whole lot of total miles on them, but these plugs have been thru 40+ dyno runs, 3 days of full-tilt-boogie at the Texas Mile, many-many canyon runs (and a few street races) so they've been subjected to lots of 19-20 PSI boost conditions in the cylinder.

I would say that 30% to 40% of my driving is pretty hard. My SRT6 is not a commuter - just a toy..

It does look like I could use a little anti-seize on the threads, but they all have a nice brown color, with no pits or scarring.

Back in they go...

 

Is there anyone here running E3's?

 

I have 1 step colder plugs and have been really happy, I've always heard people talking about "gap" in there plugs how exactly do you gap to say .35? do you need a special tool?

 

You should be able to go to the auto parts store and buy the tool... it is very simple and has different wire gauges that fit between the contacts and the adjust the contact so the sire just touches both points. The tool had an arm with notches to use for the tweeking... Once you see it you will understand.....

You could use feeler gauges too.....

 

Thanks Mike I watched a handy video on youtube and now I know what you mean with the tool, but can having the incorrect gap really make performance suffer? for example if we need them at .34 and I put them in with .40 would it hurt my performance?

 

spark is what makes it all work....too close not much spark, too wide...not a good spark...burn hotter...plugs wear out sooner...I would say if you missed by a few thousandths, not a problem....I have a one step colder plug going in soon.....

 

Thanks Doc, whats the exact gap meant for the SRT? .34? it's got me worried now, I'm off to go get me a gap tool

 

The service manual says .040 - however - NGK Spark Plugs USA

Be sure to observe proper phase shift when re-installing...

 

Great responses guys! The .040 gap in the owners manual is for stock engines. So it looks like around .035 is about just right for my mods with a 1-colder plug....

 

dont forget to "clock" the plugs so they get full burn

 

on the topic of plugs is it possible to change them yourself? or would i be better off having the dealership do it? if it is possible what tools do i need? also could you give me the gapping procedure and step by step instructions, im a pretty intuitive guy, thanks JR

 

Brian: what is phase shift and how does it apply to the plugs?


32krazy: what is clocking the plugs?

 

The polarity of the two plug wires. You get a 50/50 chance with our plugs because the plug wires can't reach to the next cylinder.

This is illustrated in the manual.



This has to do with the direction of the electrode when torqued in place -- pointing to the intake valve, the center of the cyclinder, towards the other plug, etc... to obtain optimum burn.

 

Brian, you rock! That's one of the best answers to a question I've seen here.

Thanks!

 

How in the world would you know the direction of the electrodes when you are torquing them down? NO way to tell from the outside of the plug, unless you have eyes in the cylinders???? Please help me out here...Thanks...

 

Sharpies are a handy tool.... mark a line on the plug corresponding to the electrode.....


edit: or on the socket that you can see..... just dont take it off the plug...

 

Correcto-mundo

Or insert the plug into a socket wrench with a permanent mark up one side..

To do this, you must know (via dyno or testing) in which direction the electrode placement will produce the most HP. Usually it's pointing towards the intake valve but perhaps not with dual plugs or multi-valve heads.

You may also need additional washers to ensure proper torque specs are meet when tightening.

I just torque to spec...

 

I really like this way of doing it. Never thought of that before. Thanks everyone!