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Spark plug torque specs?

Posted: Wed Oct 25, 2017 1:53 pm
by Jtcaprice
Hey guys, anyone know what the spark plug torque down recommendations are for the l77? Just bought ngk iridium IX's. Car only has 69k on the odometer, but we know how they're idled..... So I wanna go ahead and swap them tonight. Advice would be greatly appreciated. It's now my only car and I drive around 60 miles daily.

Re: Spark plug torque specs?

Posted: Wed Oct 25, 2017 2:04 pm
by smwalker
15 foot lbs. seems to be the consensus from a couple sources.

That is if you can actually get a torque wrench in there!

Re: Spark plug torque specs?

Posted: Wed Oct 25, 2017 2:08 pm
by Jtcaprice
Do you think it matters? I never torqued my other cars. I'm just really careful with this one becauseI love it so much. And I NEED it.

Re: Spark plug torque specs?

Posted: Wed Oct 25, 2017 2:12 pm
by Jtcaprice
And no I won't be able to get one down there, so I assume it doesn't matter lol

Re: Spark plug torque specs?

Posted: Wed Oct 25, 2017 2:25 pm
by smwalker
Yes it will matter to a degree. We got aluminum heads so overtorque can lead to damage. Do the easily accessible ones first with a torque wrench to get the feel for the correct setting. Then just try to get close on the harder ones.

Re: Spark plug torque specs?

Posted: Wed Oct 25, 2017 3:58 pm
by kevink
smwalker wrote:15 foot lbs. seems to be the consensus from a couple sources.

That is if you can actually get a torque wrench in there!
smwalker wrote:Yes it will matter to a degree. We got aluminum heads so overtorque can lead to damage. Do the easily accessible ones first with a torque wrench to get the feel for the correct setting. Then just try to get close on the harder ones.
15 lbs is for a new head. All subsequent installations get 11 lbs. You can easily get a torque wrench on all of the plugs. For future reference:
http://www.ls1howto.com/index.php?category=1

Re: Spark plug torque specs?

Posted: Wed Oct 25, 2017 10:12 pm
by Jtcaprice
Thanks Steve, you're always a great help.

Re: Spark plug torque specs?

Posted: Thu Oct 26, 2017 8:42 am
by CrashTestDummy
Since you have differing metals working together there, I find using anti-seize is more important than using a torque wrench. It helps prevent galled threads and stuck plugs.

Re: Spark plug torque specs?

Posted: Thu Oct 26, 2017 1:39 pm
by smwalker
kevink wrote:
15 lbs is for a new head. All subsequent installations get 11 lbs. You can easily get a torque wrench on all of the plugs. For future reference:
http://www.ls1howto.com/index.php?category=1
I read that but it did not jive with the service manual. They talk about a lower torque for reinstalling the same plugs.

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Why would it be lower for send set of plugs? Threads get weaker?

Re: Spark plug torque specs?

Posted: Thu Oct 26, 2017 1:43 pm
by smwalker
CrashTestDummy wrote:Since you have differing metals working together there, I find using anti-seize is more important than using a torque wrench. It helps prevent galled threads and stuck plugs.
Make sure and use it sparingly though. Little goes a long way and keep in mind it does effect the torque specs. No factory service manual recommends the use of it. But it does seem to help at time of removal. Make sure and get the correct kind if you are going to use a little bit of it on the threads only.