FYI, once you start making good power .030 gap will be to big on stock ignition. Also if you run plugs with out the P such as BR7ES or BR8ES they don't run as well becuase they are not a protruding electrode. When I tested them my EGT;s went up and ign timing had to go down.

 

Could you elaborate on this. I have always read/heard that the projected tip plugs are more likely to cause knock and more suseptable to damage from knock.

 

In the 4g63 head this isn't the case. It is designed to use a projected tip to place the spark in the best position for proper efficient ignition. I have even been told this from other tuners. I did try it on my own using the Denso IW24 and the NGK BR7IEX Basically both are the same plug. The both performed worse than the NGK BPR7ES / BPR7IEX. In performance I had to run more fuel and less ignition timing to be in a completely safe tune zone. My EGT's went up in all ranges and driving styles which directly made me realize that they weren't as efficient as the projected plug.

As for gap I was running about .028 on the stock turbo at any levels with no ignition problems. On a bigger turbo I couldn't run that gap over 19psi without ignition problems. I had to move my gap to .025 and be very picky to make sure the entire strap is perfect so I can run some respectible boost until I can purchase an ignition system upgrade.

 

I am wondering how a tiny difference in plugs can possibly affect the EGT which are almost totally in relation to air fuel mixture. i can understand if the plug is just causing early detonation for some reason.

 

I see that it has been a while since this thread was last visited, but I'll try this. I have nology wires installed(by myself), and I've had some idling/stalling issue, especially on inclines (ie, driveways, stopping on hills, etc). I still have the stock plugs. Can anyone tell me what is going on? I'm suspecting that I need to upgrade my plugs and gap it correctly. I'd appreciate the help.

 

I noticed that my rear bumper started to burn from where the exhaust comes out the back. Running with nology wires, anything I can do to keep the EGT down? It seems too hot at that location to be burning the bumper.

 

I just put in the NGK BPR8ES gapped at 24 and my car does not feel as fast, also during my third gear pull, car hesitated at around 6500rpm. My MR has 13000 miles, 330whp, and boosting at 22pounds. Should I stick with stock plugs NGK IGR7ES which are running good. I figured having 100whp more over stock I should change the plugs out. Has anyone used NGK BPR7ES-11 or NGK BKR7ES-11.

 

Do they make BPR8EIX?