Spark Plugs, Timing, and more

[Higgs Boson]

Originally Posted by ss/rs-matt

So what is the heat range of the stock plug? If I wanted to get a colder plug, how do I know its colder?

if it is ngk then a colder plug is a higher number. tr6 is colder than tr5. tr5 is stock heat range. tr55 is the same heat range as tr5 but it's pregapped wider. either will work, always check your gaps before installing though.

ngk is the way to go in any case, IMO.

ngk tr5 for bone stock
tr6 for light mods

for nitrous applications

ngk bkr6 or bkr7
they have a recessed tip

[Anthony @ LG Motorsports]

Results from a week of driving (did the plug change last week)

Log records were done last night and this morning, this is the worse of the two runs (approx 32mins of driving combined stop and go and highway, same as before log runs).

NGK TR6iX plug after 300 miles (approx)

Notice no more pepper marks.

Stock AC plug vs NGK

Notice the change in tip projection from the end of the plug vs stock

Almost to ZERO knock!


Need to dig a bit more into the table to see if this was on decell, if it was just a pop or possibly just general noise or the pump fuel itself. Either way we have killed 99% of the knock that was there before hand.


So the long and short of it.

Listen to your car, it will tell you what it is going to want. In this case we have a stock car that is running into some timing issues and the result is a better running car with a slightly colder plug. Those of you that are modifying the car, which most of us are. You can benefit in a number of ways because you are more than likely creating more cylinder pressure, more HP, and more heat. A colder plug will allow more timing and less chance of detonation.

For those not wanting to make a tuning change in the ECM this is a good way to help your car on track as well. Just like running better engine oils and better fuels on track under heavy load conditions.


It should be noted that the factory does want a very clean and hot burn for emissions. Those that rarely drive the cars, or do not drive them that hard, this might not be for you.

[Higgs Boson]

great post and thread, Anthony.

[Anthony @ LG Motorsports]

Originally Posted by Higgs Boson

if it is ngk then a colder plug is a higher number. tr6 is colder than tr5. tr5 is stock heat range. tr55 is the same heat range as tr5 but it's pregapped wider. either will work, always check your gaps before installing though.

ngk is the way to go in any case, IMO.

ngk tr5 for bone stock
tr6 for light mods

for nitrous applications

ngk bkr6 or bkr7
they have a recessed tip

Which is funny because a TR55, has less of a projected tip than that of a stock plug.

When I get some time, I'll cut them part to see how far the insulator goes into the body of the plug and get some more in depth measurements.

[BowlingSS]

After this read I am thinking about taking my AC Delco Stock Plugs back to get the NGK ones that are one number colder. I have headers and a CAI right now.

Bill

[ss/rs-matt]

Any benefit to running the tr6ix vs the tr6 other than life of the plug?

[Higgs Boson]

Originally Posted by ss/rs-matt

Any benefit to running the tr6ix vs the tr6 other than life of the plug?

no, only life. tr6 are 2 dollars each. not worth it for iridium, IMO.

[less2010]

what would you gap these plugs to,would it be stock gap?

[ackeight]

I'm about to slap on some headers and get a tune. Should I get the tr6's before the tune? I haven't had any problem to date with an intake or Dallas 93 pump gas.

[Higgs Boson]

Originally Posted by less2010

what would you gap these plugs to,would it be stock gap?

stock gap unless you are blown or sprayed.

Originally Posted by ackeight

I'm about to slap on some headers and get a tune. Should I get the tr6's before the tune? I haven't had any problem to date with an intake or Dallas 93 pump gas.

if you are getting a tune you can use tr6 and the tuner will either not have to pull (as much) timing and may be able to add a little in some cases vs stock.

[kaler]

Would you guys recommend tr6 or 7's in my application? (mods in my sig) BTW I am having a issue with the ecm pulling 6-8 deg. Of timing.

[Higgs Boson]

Originally Posted by kaler

Would you guys recommend tr6 or 7's in my application? (mods in my sig) BTW I am having a issue with the ecm pulling 6-8 deg. Of timing.

tr6

[less2010]

Originally Posted by Higgs Boson

stock gap unless you are blown or s

if you are getting a tune you can use tr6 and the tuner will either not have to pull (as much) timing and may be able to add a little in some cases vs stock.

thanks for the info.

[kaler]

Originally Posted by Higgs Boson

tr6

Thanks. After Anthony's post I hope I get the same results, it has been a pain in the @ss trying to figure out why it has been pulling so much timing it never crossed my mind that the stock plugs could be causing it.