School me on spark plugs
Like Freddie says just stick with the BPR7ES and gap them smaller. Depending on boost I would start at .024 and work your way to .020 and see how it goes. I have been gapping mine to .020 on 92 pump and 28 psi for quite some time and everything seems to be good.
I've been reading up on this.. The best thing to do is simply read the existing plug in your engine, it will tell you whether it is too hot or too cold.
If you pull a plug and find a nice off-white or slightly tan/gray color with new-looking electrode shapes and no evidence of problems, you've got it right.
If you run 8's and find fouling, it suggests that your running a too-cold plug. This is the best of the worst situations, just go back to the stock 7's.
If the plug is burned white and has slight melting, you're running a too-hot plug, which is very bad. Running a plug that is too hot can put it in the pre-ignition zone, this is much worse than running a cold plug that will just foul over time. Go buy some 8's.
I've been running 8's on an Evo with minor modifications for about 6 months, I generally drive on open roads and do my best to avoid city driving. No fouling at all, so I'm sticking with mine.
If you pull a plug and find a nice off-white or slightly tan/gray color with new-looking electrode shapes and no evidence of problems, you've got it right.
If you run 8's and find fouling, it suggests that your running a too-cold plug. This is the best of the worst situations, just go back to the stock 7's.
If the plug is burned white and has slight melting, you're running a too-hot plug, which is very bad. Running a plug that is too hot can put it in the pre-ignition zone, this is much worse than running a cold plug that will just foul over time. Go buy some 8's.
I've been running 8's on an Evo with minor modifications for about 6 months, I generally drive on open roads and do my best to avoid city driving. No fouling at all, so I'm sticking with mine.
I think generally you are better off with protruding electrodes. If your car won't let you then thats a different story. Getting the flame out in the chamber away from the boundary layer is a good thing.
Use heat range 7 unless you have some sort of monster motor. I love the idea that my motor needs an 8 but the plugs just don't show it.
26psi,valves,cams...
Use heat range 7 unless you have some sort of monster motor. I love the idea that my motor needs an 8 but the plugs just don't show it.
26psi,valves,cams...
btw here is a thread about reading plugs that is a step beyond most of what is out there. ITs discussing carbed motors but...
http://www.innovatemotorsports.com/f...&postcount=102
http://www.innovatemotorsports.com/f...&postcount=102
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smokedmustang
General Engine Management / Tuning Forum
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Jun 5, 2005 09:04 AM






