Any dangers to using FC leading spark plugs?
#1
Any dangers to using FC leading spark plugs?
79 SA with 12a Nikki, 2 1/2" exhaust, header, Holley electric fuel pump...
This car came with 8 NGK BR9ES plugs. I absolutely hate these plugs! They foul up like crazy to where it doesn't want to start and is erratic at idle. On a whim I swapped in a pair of 2nd gen LEADING 7 range plugs I had laying around from my last FC project. I kept the BR9ES plugs in as TRAILING. BAM started right up and the idle was super smooth and rock solid at 800 RPM after a little tunnig. No pops, no stutters, just smooth. It revs great. I drove it up and down the street (no hot rodding, just cruising through the gears) and it drove fantastic.
My question is I've seen threads here and there about using 2nd gen plugs. I just want to make sure it doesn't pose any threat to my seals or anything by being a more powerful spark.
This car came with 8 NGK BR9ES plugs. I absolutely hate these plugs! They foul up like crazy to where it doesn't want to start and is erratic at idle. On a whim I swapped in a pair of 2nd gen LEADING 7 range plugs I had laying around from my last FC project. I kept the BR9ES plugs in as TRAILING. BAM started right up and the idle was super smooth and rock solid at 800 RPM after a little tunnig. No pops, no stutters, just smooth. It revs great. I drove it up and down the street (no hot rodding, just cruising through the gears) and it drove fantastic.
My question is I've seen threads here and there about using 2nd gen plugs. I just want to make sure it doesn't pose any threat to my seals or anything by being a more powerful spark.
#7
Lives on the Forum
iTrader: (13)
If you want to get the full benefit of those plugs then I recommend that you upgrade to the FB electronic ignition and run the 2nd gen leading coil.
In my SE I gained 1.3 MPG by running the 2nd gen leading coil. This has been verified twice on test drives recording the mileage with the 2nd gen leading coil and then with the stock FB coil. :-)
In my SE I gained 1.3 MPG by running the 2nd gen leading coil. This has been verified twice on test drives recording the mileage with the 2nd gen leading coil and then with the stock FB coil. :-)
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#8
Good to hear. I plan on buying an FC coil to do the direct fire setup, but for now I just want to get it drivable and reliable. My current setup seems to be all of the above.
79 points, 2nd gen LEADING 7 spark plugs, 1st gen TRAILING 9 spark plugs, 12a with Nikki and cold air ram modification, emissions removed, new air filter, Holley electronic fuel pump, MR.Gasket fuel pressure regulator set at 2.5 PSI, new fuel filter, Pace Setter header, 2 1/2 inch exhaust, premix.
I think that's about it as far as bolt ons etc..
79 points, 2nd gen LEADING 7 spark plugs, 1st gen TRAILING 9 spark plugs, 12a with Nikki and cold air ram modification, emissions removed, new air filter, Holley electronic fuel pump, MR.Gasket fuel pressure regulator set at 2.5 PSI, new fuel filter, Pace Setter header, 2 1/2 inch exhaust, premix.
I think that's about it as far as bolt ons etc..
#10
Famous Taillights
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To answer your question directly, no there is no problem running that plug at all. I got my SA with both FC leading and trailing plugs(albeit electronic dizzy) and had no issues. But as they've said to get the full benefit of the plug it needs the FC coil, which I did and am still using the FC leading while using the stock FB BR8EQ14 plugs in trailing. I also have full exhaust with emissions delete and an RB air box. My car will break the tires loose in 2nd gear, even with the 4-Speed gearing and Sumitomo HTR200's in 205/60-13's
#11
Lapping = Fapping
iTrader: (13)
It was hyper4mance2k that said the 2nd gen plugs can crack housings on the inside at the chrome. I personally have never seen this, but I will say that if you install them in a used engine, the compression of the existing carbon egainst the slightly longer ground electrode might lead to problems. I've noticed they can take a little effort to get tight as they get through the carbon layer.
It's probably safer to install 2nd gen plugs in a freshly rebuilt engine whose spark plugs holes are clean, or new housings.
It's probably safer to install 2nd gen plugs in a freshly rebuilt engine whose spark plugs holes are clean, or new housings.
#12
Stu-Tron Get Yo Groove On
iTrader: (4)
Good to hear. I plan on buying an FC coil to do the direct fire setup, but for now I just want to get it drivable and reliable. My current setup seems to be all of the above.
79 points, 2nd gen LEADING 7 spark plugs, 1st gen TRAILING 9 spark plugs, 12a with Nikki and cold air ram modification, emissions removed, new air filter, Holley electronic fuel pump, MR.Gasket fuel pressure regulator set at 2.5 PSI, new fuel filter, Pace Setter header, 2 1/2 inch exhaust, premix.
I think that's about it as far as bolt ons etc..
79 points, 2nd gen LEADING 7 spark plugs, 1st gen TRAILING 9 spark plugs, 12a with Nikki and cold air ram modification, emissions removed, new air filter, Holley electronic fuel pump, MR.Gasket fuel pressure regulator set at 2.5 PSI, new fuel filter, Pace Setter header, 2 1/2 inch exhaust, premix.
I think that's about it as far as bolt ons etc..
#14
All I know is that it runs better than it ever has before. Granted I've only had the car for 2 months... The 12a is virtually identical to the 13b more or less though correct? I don't see how it would cause any problems. I cleaned away some of the carbon around the plugs holes a couple weeks ago with Seamfoam and a rag. They tighten pretty easily.
#23
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the only spark plug that is PHYSICALLY a problem is the Rx-8 trailing ones, they are LONGER than the previous designs.
as far as power goes, i like to stick with the stock plug for the ignition system. if you want a realy upgrade the rx8 leadings are built like the racing plugs but in a "normal" heat range.
plenty of SAE papers to document which plug works better when, although in a stock setup the differences are very slight
as far as power goes, i like to stick with the stock plug for the ignition system. if you want a realy upgrade the rx8 leadings are built like the racing plugs but in a "normal" heat range.
plenty of SAE papers to document which plug works better when, although in a stock setup the differences are very slight
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