I was thinking about the spark plugs I run and then how so many people choose to use different ones on the EVO. You would think that most would use a certain type but after doing some searching I found the most commonly used ones are: (NGK)

BPR
BP
BR

I tried searching even on Google but I could not find any good info on the performance differences of them.

Im aware the BR (lacking P) means non-protruding tip and obviously vice versa, but what is the gain/loss from using such combinations.

I was reccomended to use the BR8ES by Dynoflash and I have been since my last tune and I have never once had a misfire or a problem with them. I have them gapped to .026 and they last about 6-7k miles.

Can someone explain WHY the protruding tip theory and why its better or worse for our motors...

 

It is my understanding (NOT and expert on this) that a protruding tip is good for fuel economy and emissions, but is more prone to "spark blowout" under high boost / high RPM situations.

Keith

 

I use the bpr8es and never had a blow out problem.

 

The BR8ES´s run about 30 degrees cooler than the BPR8ES´s. I learned that on here (and I´m far removed from being an expert). I think that it refers to combustion chamber temps.

 

Interesting stuff!

 

This is not a direct answer to your question, however I thought these links would be beneficial in a spark plug thread.

http://www.eric-gorr.com/techarticles/sparkplugs.html

http://www.centuryperformance.com/spark.asp <--page 1

http://www.centuryperformance.com/spark2.asp <--page 2

http://www.ngksparkplugs.com/techinf...q/faqread2.asp

 

well i use bpr7es and never had a problem. i dont no a thing about spark plugs other then no spark no go.

 

I have used the BPR8ES plugs for sometime now.
I switched from the factory coils to the Buschur COP and am now running the BR8ES plugs.
These plugs dont seem to make much of a diference when driving under normal day to day operation. But when you get on the dyno and your pushing the car and the boost goes up, you can see that the spark seems to be stronger. No expert but i have tried both sets of plugs and I believe the BR plugs are better at higher boost than the BPRs.

 

I use the BR8ES and havent had a problem yet , so i say the br8es are for big turbos and high boost, so it depends on what you have. really everyone trys one and if they like them they stay with them untill there is a problem.

 

With regards to the projected type spark plugs I believe that the projected plug is more centralized in the combustion chamber (aka cylinder) and therefore the spark "kernel" as it is often referred to is more efficient because it is better positioned. In addition by extending a bit further into the cylinder it benefits from being "instream" of the intake charge which cools it as the fresher air enters the cylinder.

I am not an automotive engineer, just a racer with a passion for cars and making them faster within my abilities, so don't flame me if you disagree. Rather post your thoughts and comments so we can all learn something useful about this.

 

I wish someone from NGK would reply lol

 

^ +1

 

hey you dont happen to know the stock number on those plugs do you? it will be the 4 digit number on the end of the box.....thanks

 

Straight from the NGK website....

http://www.ngksparkplugs.com/techinf...000&country=US

"If the tip temperature is higher than 850°C the spark plug will overheat which may cause the ceramic around the center electrode to blister and the electrodes to melt. This may lead to pre-ignition/detonation and expensive engine damage. In identical spark plug types, the difference from one heat range to the next is the ability to remove approximately 70°C to 100°C from the combustion chamber. A projected style spark plug firing tip temperature is increased by 10°C to 20°C."

You want to run the hottest plug possible that doesn't cause detonation/pre-ignition. A projected tip gives you an additional step between heat ranges.

 

Hottest plug as in higher number like rather 8 than 7?