HHR SS Sparkplug Witchcraft....LOL
01-11-2018, 08:04 PM
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HHR SS Sparkplug Witchcraft....LOL
Ask 100 people what's the best sparkplug, & you'll get many different answers...
Our LNF engine is a mature product, being 10 years old, so every reasonable plug has been tryed...
There is but one plug that should be used.... The Stock Plug ...
GM part# 12617309
AC Delco# 41-108
NGK# 5476 ILTR5D
NGK makes this plug for GM & AC Delco, & sometimes you'll find the # 5476 stamped on GM & AC Delco plugs...
They come pre-gapped at .035 , which is sort of fine, & is what I call the 'emissions' gap.
This gap should be changed to make you LNF run better...
If you have any type of 'tune', including the GM Performance 'tune' you must reduce the gap to .032, our engines love a .032 gap...
Even if you have a stock engine, reduce the gap to .032, it makes for a smoother running 'buggy'.
It really is 'rocket-science' to reduce the gap to .032, as you can easily destroy the plugs if you don't know what you are doing...
The 'heat' range of this plug is fine, & even the 300hp Ford EcoBoost engine uses this same heat range.
When our LNF engine was 1st put into the 2007 Pontiac Solstice, GM used a plug that was one 'heat' range 'colder'...
This proved to make the LNF 'unstable' in certain environments, & operating conditions, so GM quickly changed it, starting in the 2008 model year...
NGK does say that if you are making 70-100 more HP, you could try a plug that is one 'heat' range colder, if you know what you are doing, & know how to 'read' a plug, & know what problems to look for when going one step 'colder'...
The correct one range 'colder' plug is NGK 3787 ILTR6A-86 which comes pre-gapped at .031
Since it's so close to the ideal LNF gap of .032, it nor recommended to change it as you can easily damage the plugs...
I have used the stock plug at .032 for years with no issues at all...
But just for 'fun', I will try the 3787 plug this summer to see if it makes a difference in power output...
Some 'testers' say that more power results from reduced 'knock'...
I do have some 'knock', but have always believed that my 'knock' was the result of the PCM reducing my timing, due to me exceeding some of the 'set' conditions that the PCM is looking for...
Our LNF engine is a mature product, being 10 years old, so every reasonable plug has been tryed...
There is but one plug that should be used.... The Stock Plug ...
GM part# 12617309
AC Delco# 41-108
NGK# 5476 ILTR5D
NGK makes this plug for GM & AC Delco, & sometimes you'll find the # 5476 stamped on GM & AC Delco plugs...
They come pre-gapped at .035 , which is sort of fine, & is what I call the 'emissions' gap.
This gap should be changed to make you LNF run better...
If you have any type of 'tune', including the GM Performance 'tune' you must reduce the gap to .032, our engines love a .032 gap...
Even if you have a stock engine, reduce the gap to .032, it makes for a smoother running 'buggy'.
It really is 'rocket-science' to reduce the gap to .032, as you can easily destroy the plugs if you don't know what you are doing...
The 'heat' range of this plug is fine, & even the 300hp Ford EcoBoost engine uses this same heat range.
When our LNF engine was 1st put into the 2007 Pontiac Solstice, GM used a plug that was one 'heat' range 'colder'...
This proved to make the LNF 'unstable' in certain environments, & operating conditions, so GM quickly changed it, starting in the 2008 model year...
NGK does say that if you are making 70-100 more HP, you could try a plug that is one 'heat' range colder, if you know what you are doing, & know how to 'read' a plug, & know what problems to look for when going one step 'colder'...
The correct one range 'colder' plug is NGK 3787 ILTR6A-86 which comes pre-gapped at .031
Since it's so close to the ideal LNF gap of .032, it nor recommended to change it as you can easily damage the plugs...
I have used the stock plug at .032 for years with no issues at all...
But just for 'fun', I will try the 3787 plug this summer to see if it makes a difference in power output...
Some 'testers' say that more power results from reduced 'knock'...
I do have some 'knock', but have always believed that my 'knock' was the result of the PCM reducing my timing, due to me exceeding some of the 'set' conditions that the PCM is looking for...
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