Spark Plug Know How.....What to gap them at and how to tell if thay are fouled???????

[umiami80]

Like the title states I am looking to replace my Sparkplugs soon and doing so with NGK BPR8ES. I haven't changed them in ALMOST a year and about 15,000 Miles So it may be time to do so.


Question......

On a stock ECU controlling the spark along with Cams and pump gas, what would the proper gap be without fear of blowing it out? What about race gas and say 25PSI on the stock turbo?


When you pull the plug, how can you tell if it is fouled exctly?


Thanks again.

[Fourdoor]

If the plugs were fouled you can tell it when driving, stumbles pretty bad. If they look dark and sooty when you pull them they were probably fouled.

Now, I would NOT recomend the colder heat range with our cars, even at elevated boost levels and such they will foul constantly if you have the colder plugs. I would go with the BPR7ES's myself.

Keith

[umiami80]

EVEN IF my car was flashed with BPR8ES???????????????????????????????????????????? ????????????

[Fourdoor]

The spark plugs have no effect on your flash, but the cold range plugs are much more likely to foul out and cause ignition problems than the stock heat range plugs.

Keith

[turbolarry]

At 25+psi.; BPR7ES's gapped to .26-.28.
Here's some things to look for too;
http://densoiridium.com/howtoreadusedplugs.php