jliltd
Well Known Member
I have been reading VAF and talking to folks who use NGK automotive spark plugs with their PMags. From what I have learnt I gather the following:
First and foremost we should use plugs with a solid post terminal (tip), not the equivalent model number with the screw-off tip. There have been issues over time with the screw off tips loosening and arcing leading to ignition trouble. There have been workarounds like crimping hard on the tips with side cutters etc. in order to alleviate the loosening but why not avoid the whole mess by sticking to the solid tip plugs.
Next, I gather that there are 2 poplular heat ranges....
For compression ratios up to 9:1
NGK BR8ES Part Number 3961 with solid/permanent tip – standard plug
Optional Upgrade: NGK BR8EIX Part Number 6747 with solid/permanent tip – Iridium
The 8 heat range is the suggested rating in the EMag Air installation manual.
For compression ratios above 9:1
NGK BR9ES Part Number 7788 with solid/permanent tip – standard plug
Optional Upgrade: NGK BR9EIX Part Number 3089 with solid/permanent tip -- Iridium
I also hear from folks who buy the cheaper standard plugs and replace them every second oil change or so (~ 100 hrs), whereas the Iridium models can go a few hundred hours (~500). The Iridiums cost 3 or 4 times more than the standard plugs.
I would like to hear comments about my understanding of the above.
Jim
First and foremost we should use plugs with a solid post terminal (tip), not the equivalent model number with the screw-off tip. There have been issues over time with the screw off tips loosening and arcing leading to ignition trouble. There have been workarounds like crimping hard on the tips with side cutters etc. in order to alleviate the loosening but why not avoid the whole mess by sticking to the solid tip plugs.
Next, I gather that there are 2 poplular heat ranges....
For compression ratios up to 9:1
NGK BR8ES Part Number 3961 with solid/permanent tip – standard plug
Optional Upgrade: NGK BR8EIX Part Number 6747 with solid/permanent tip – Iridium
The 8 heat range is the suggested rating in the EMag Air installation manual.
For compression ratios above 9:1
NGK BR9ES Part Number 7788 with solid/permanent tip – standard plug
Optional Upgrade: NGK BR9EIX Part Number 3089 with solid/permanent tip -- Iridium
I also hear from folks who buy the cheaper standard plugs and replace them every second oil change or so (~ 100 hrs), whereas the Iridium models can go a few hundred hours (~500). The Iridiums cost 3 or 4 times more than the standard plugs.
I would like to hear comments about my understanding of the above.
Jim
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