BrainFreezE

iTrader: (2)

I Have seen tons of different threads about different gaping and they are all years old thread. Up to current date what is the recommended gap for ls1 engine?

LS6427

iTrader: (2)

.055 is the best gap for ANY LS1 engine that is either bone stock or heavily modded......NORMALLY ASPIRATED pump gas. Bone stock up to 600-700 RWHP.

Not including Nitrous, Boosted or race gas high compression all out N/A race engines.

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dailydriver

I thought that the Iridiums were NOT supposed to be gapped, or even attempted to be gapped??

demonspeed

iTrader: (7)

X2. Iridium tips are very delicate and it is not recommended to even check the gap. GM went to iridium plugs sometime in the mid-2000's (ACDelco 41-110) for all LS engines. These are pre-gapped at .040, IIRC.

Now, what LS6427 is actually true if we're talking normal plugs. "Back in the day" the default was NGK TR55 @ .055. That's still a safe default even today, but I've been very happy with the OE iridium plugs since doing my longtubes.

LS6427

iTrader: (2)

Yea, I was talking in general....... .055

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