Evo Engine / Turbo / DrivetrainEverything from engine management to the best clutch and flywheel.
Sponsored by: World Racing
Welcome to EvolutionM.net!
Welcome to EvolutionM.net.
You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!
Copper plugs are cheaper but need to be changed more often. Plugs with the heatrange of 7 should be good for boost levels of 25 and below. If you're running more than that, you should probably go for heatrange 8.
Last edited by MasterNater; Feb 9, 2009 at 09:51 PM.
I think my BPR's knock less than BR.. it may be subjective... but theory goes that the closer the spark to the center of the chamber (with projected/protruding design) — to ignite the mixture from the center — the better the results/burn. If it's burning from the middle the process should happen faster (good for power and knock prevention). Non-protruding/projected tips were designed for smaller clearance chambers to avoid the piston hitting the plug tip.
It's also thought that BR is a half step colder than BPR..
All above, FWIW...
^ Thinking about it that does make a lot of sense. I did run the BPR's for a while like I said though the car seem to run a bit smoother from the BR's. This was on the stock heat range with full boltons.
Now I'm big turbo and switched to the 8's. I immediately just picked up the BR's as I ran them in the 7's.
I'm going to grab BPR8's and see if I can feel any difference good or bad from the BR8's. I'll put the car into various situations and log each (Not sure that I'll see anything).
I def see where the theory of the protruding tip should produce a more complete burn.
Drives: '01 Audi S4, '04 RS(AS), '08 WW X MR, G500, Toyota Hilux 3.0
Originally Posted by mplspilot
I think my BPR's knock less than BR..
There is another school of thought which contends that a protruded tip, such as that of the BPR's is more prone to preignite the air/fuel mixture than the BR's recessed tip is. In this scenario, the hot, glowing tip, protruding further down into the combustion chamber, auto-ignites the air/fuel mixture prematurely, before the piston reaches TDC on the compression stroke, and before the sparkplug fires.